Add Revit requirements handoff

AGENTS.md

@@ -283,17 +283,23 @@ that have remained unchanged. ProjectDevice create, update, delete and
 global-to-project copy API/UI paths use these persistent commands and track the
 returned project revision. ProjectDevice synchronization/disconnect API and UI
 paths do the same; their undo action uses the project-wide history endpoint.
-Project voltage settings use the persistent `project.update-settings` command.
+Project settings use the persistent `project.update-settings` command. Project
-Both voltage defaults change in one revision and Undo/Redo restores them
+metadata, both voltage defaults and the enabled distribution-board supply types
-together; the project PUT route requires `expectedRevision`.
+change in one revision and Undo/Redo restores them together; the project PUT
+route requires `expectedRevision`. The system catalog is `AV`, `SV`, `EV`,
+`USV`, `MSR`, `SiBe`; at least one must be enabled and a type used by a board
+cannot be disabled.
 Distribution-board setup uses `distribution-board.insert` with a complete
 stable snapshot of the board, circuit list and four default sections. Its
 inverse removes only the same unchanged and still-empty structure; the POST
 route requires `expectedRevision` and returns the updated history state.
+Distribution-board floor assignment and a project-enabled supply type use
+`distribution-board.update`; both values are snapshot/export fields and one
+persistent undo step.
 Floor and room setup use `project-floor.insert` and `project-room.insert` with
 complete stable snapshots. Their inverses remove only unchanged records and
-reject floors with assigned rooms or rooms referenced by device rows or
+reject floors with assigned rooms/distribution boards or rooms referenced by
-retained upgrade data. Both POST routes require `expectedRevision` and return
+device rows or retained upgrade data. Both POST routes require `expectedRevision` and return
 the updated history state.
 
 Required operations:

docs/README.md

@@ -27,8 +27,10 @@ ausdrücklich getrennt und dürfen nicht als bereits implementiert verstanden we
 ## Zukunftsarchitektur
 
 - [Projektversionen und externer Modellaustausch](project-history-and-external-model-architecture.md)
+- [LLM-Kontext für die Revit-Anforderungsplanung](revit-requirements-llm-context.md)
 - [Zukünftige Dimensionierung](spec/06-future-sizing-and-calculations.md)
 - [Roadmap und Phasen](spec/07-implementation-phases-todo.md)
+- [Aktueller Produkt-Backlog](spec/08-current-product-backlog.md)
 
 ## Fachliche Referenzspezifikation
 

docs/circuit-list-editor-api.md

@@ -145,11 +145,18 @@ synchronizes linked circuit rows implicitly.
 
 - `PUT /projects/:projectId`
   - request:
-    `{ "expectedRevision": 12, "singlePhaseVoltageV": 230, "threePhaseVoltageV": 400 }`
+    `{ "expectedRevision": 12, "singlePhaseVoltageV": 230, "threePhaseVoltageV": 400, "enabledDistributionBoardSupplyTypes": ["AV", "MSR", "SiBe"], ...projectMetadata }`
   - executes `project.update-settings` as one atomic revision
   - response:
     `{ "project": { ... }, "revision": { ... }, "history": { ... } }`
-  - persistent Undo/Redo restores both voltage values together
+  - persistent Undo/Redo restores metadata, voltage values and the enabled
+    distribution-board supply types together; project-device and circuit
+    voltages are recalculated from the restored project settings in the same
+    transaction
+  - project-device and circuit voltage are derived values and are not accepted
+    as editable frontend fields
+  - at least one of `AV`, `SV`, `EV`, `USV`, `MSR`, `SiBe` must be enabled;
+    a supply type currently used by a distribution board cannot be disabled
   - unchanged values are rejected without creating a revision; a stale
     revision returns `409 PROJECT_REVISION_CONFLICT`
 
@@ -181,7 +188,11 @@ returns HTTP `409` with `PROJECT_HISTORY_OPERATION_UNAVAILABLE`.
 ### Distribution Board Setup
 
 - `POST /projects/:projectId/distribution-boards`
-  - body: `{ "name": "UV-02", "expectedRevision": 12 }`
+  - body:
+    `{ "name": "UV-02", "floorId": "floor_1", "supplyType": "SV", "expectedRevision": 12 }`
+  - `floorId` may be `null`; a non-null floor must belong to the project
+  - `supplyType` is one of `AV`, `SV`, `EV`, `USV`, `MSR` or `SiBe` and must
+    be enabled in the project settings
   - executes `distribution-board.insert` with stable ids for the distribution
     board, its circuit list and all four default circuit sections
   - response:
@@ -189,6 +200,11 @@ returns HTTP `409` with `PROJECT_HISTORY_OPERATION_UNAVAILABLE`.
   - persistent Undo removes only the unchanged and still-empty generated
     structure; Redo restores the same ids
   - stale revisions return `409 PROJECT_REVISION_CONFLICT`
+- `PUT /projects/:projectId/distribution-boards/:distributionBoardId`
+  - body:
+    `{ "floorId": null, "supplyType": "AV", "expectedRevision": 13 }`
+  - executes `distribution-board.update`; floor and supply type are restored
+    together by persistent Undo/Redo
 
 ### Project Floors and Rooms
 
@@ -203,8 +219,9 @@ returns HTTP `409` with `PROJECT_HISTORY_OPERATION_UNAVAILABLE`.
     and must belong to the project when present
   - response: `{ "room": { ... }, "revision": { ... }, "history": { ... } }`
 - Persistent Undo removes only unchanged, unreferenced records. A floor with
-  assigned rooms and a room referenced by device rows or retained upgrade data
+  assigned rooms or distribution boards and a room referenced by device rows
-  are rejected instead of silently clearing foreign keys.
+  or retained upgrade data are rejected instead of silently clearing foreign
+  keys.
 - Stale revisions return `409 PROJECT_REVISION_CONFLICT`.
 
 ### Tree Endpoint

docs/circuit-list-editor-architecture.md

@@ -37,6 +37,9 @@ The pure grid modules have no React state and are covered by focused unit tests.
     - `cosPhi`
     - room snapshots
     - category/cost group and related row attributes
+    - canonical `phaseType` values `single_phase` or `three_phase`; the
+      frontend always presents these as `1-phasig` or `3-phasig` and edits
+      them through a selection control
 - `ProjectDevice`
   - Reusable device template entity at project level.
   - Can be linked to `CircuitDeviceRow` entries, with copied display values on insert.

docs/current-architecture.md

@@ -149,8 +149,14 @@ Upgrade-only-Verknüpfungen und Migrationsnachweise bleiben erhalten, obwohl sie
 nicht Bestandteil des logischen Snapshots sind.
 Die Projektseite bindet diese APIs in einem einklappbaren Bereich
 „Versionen und Sicherungspunkte“ ein. Dort können Benutzer Sicherungspunkte
-benennen, nach expliziter Bestätigung wiederherstellen und die paginierte
+benennen, jeden aufgeführten benannten oder automatischen Stand nach
-Revisions-Timeline mit deutschen Quellen- und Änderungsbezeichnungen lesen.
+expliziter Bestätigung wiederherstellen und die paginierte Revisions-Timeline
+mit deutschen Quellen- und Änderungsbezeichnungen lesen. Die Snapshot-Liste
+ordnet jede positive `sourceRevision` serverseitig ihren unveränderlichen
+Revisionsmetadaten zu. Dadurch zeigt auch ein älterer automatischer Stand die
+auslösende Änderung, ohne eine zweite frei formulierte Beschreibung zu
+speichern oder von den zuletzt paginiert geladenen Timeline-Einträgen
+abzuhängen. Revision null wird als Projektstart dargestellt.
 Projektweites Rückgängig/Wiederholen bleibt im Kopf dieses Bereichs auch im
 eingeklappten Zustand erreichbar. Die Verfügbarkeit stammt direkt aus den
 persistierten Server-Stacks; nach einer Historienaktion oder einem Restore lädt
@@ -167,6 +173,26 @@ Felder und vollständiger Zeilenbestand unverändert sind.
 Der Editor erzeugt die vollständigen Move-Zuweisungen aus dem geladenen Tree,
 vergibt für neue Ziele vor dem Kommando eine stabile UUID und führt das
 Toolbar-Undo/Redo über die projektweite Historie aus.
+Die Projektgerätepalette belegt keine permanente Layoutspalte mehr. Sie wird
+über die Editor-Toolbar als überlagernder Drawer geöffnet, während das
+Stromkreis-Grid standardmäßig die gesamte verfügbare Breite nutzt. Auswahl,
+Schnelleinfügen und die vorhandenen Drag-and-drop-Payloads bleiben im Drawer
+unverändert verfügbar; während eines aktiven Projektgeräte-Drags kann er nicht
+geschlossen werden. Der Drawer liegt am rechten Fensterrand und verdeckt damit
+nicht die führenden BMK- und Anzeigenamenspalten. Das Grid zeigt Geräte- und
+Stromkreisleistungen in einer gemeinsamen Spalte `Gesamtsumme`: Gerätezeilen
+verwenden `rowTotalPower`, Stromkreis-Sammelzeilen `circuitTotalPower`.
+Zahlen werden ausschließlich für die Anzeige deutsch und begrenzt formatiert;
+gespeicherte Werte und Bearbeitungsentwürfe behalten ihre volle Genauigkeit.
+Jeder Abschnitt liefert und zeigt seine aufsummierte Stromkreisleistung. Die
+Stromkreisliste zeigt außerdem die ungefilterte Gesamtleistung des Verteilers,
+den am Verteiler gespeicherten Gleichzeitigkeitsfaktor und die daraus
+abgeleitete Gesamtleistung unter Berücksichtigung dieses Faktors. Sortierung
+und Filter verändern diese fachlichen Summen nicht.
+Reihenfolge und Sichtbarkeit der Grid-Spalten sind reine UI-Präferenzen. Sie
+werden im Browser unter einem projektspezifischen Schlüssel gespeichert und
+deshalb beim Wechsel zwischen Verteilern desselben Projekts wiederverwendet,
+ohne Projektrevisionen oder fachliche Snapshots zu erzeugen.
 `circuit.reorder-section` speichert die erwartete und neue Sortierposition
 jedes Stromkreises eines vollständigen Abschnitts. Forward, Undo und Redo
 ändern ausschließlich `sortOrder`; Stromkreisblöcke, Gerätezeilen und BMKs
@@ -209,23 +235,66 @@ unverknüpft und vollständig unverändert sind. Gerät, Linkänderungen, Revisi
 und Historienstapel teilen dieselbe Transaktion. Create, Import aus der globalen
 Gerätebibliothek und Delete laufen über dieselbe Command-Grenze; ihre Antworten
 liefern Gerät und aktualisierten Historienstand an die Projektseite zurück.
-`project.update-settings` versioniert die beiden Projekt-Standardspannungen als
+`project.update-settings` versioniert Projektname, interne und externe
-eine atomare Änderung. Der Store leitet das inverse Kommando aus dem
+Projektnummer, Bauherr, Beschreibung, beide Standardspannungen sowie die im
-gespeicherten Projekt ab und schreibt Werte, Revision und Historienstapel
+Projekt freigeschalteten Verteiler-Netzarten als eine atomare Änderung. Der
-gemeinsam. `PUT /api/projects/:projectId` verlangt deshalb
+Systemkatalog besteht aus `AV`, `SV`, `EV`, `USV`, `MSR` und `SiBe`; mindestens
-`expectedRevision`, liefert Projekt plus aktualisierten Historienstand und
+eine Netzart muss aktiv bleiben und eine bereits von einer Verteilung
-besitzt keinen separaten direkten Settings-Schreibweg mehr.
+verwendete Netzart kann nicht deaktiviert werden. Die Projektseite bearbeitet diese Angaben in einem
+beschrifteten Einstellungsmodal statt in einer permanenten Formularkarte. Der
+Store leitet das inverse Kommando aus dem gespeicherten Projekt ab und schreibt
+Werte, Revision und Historienstapel gemeinsam. `PUT /api/projects/:projectId`
+verlangt deshalb `expectedRevision`, liefert Projekt plus aktualisierten
+Historienstand und besitzt keinen separaten direkten Settings-Schreibweg mehr.
+Kommando- und Snapshot-Versionen vor dieser Erweiterung bleiben les- und
+ausführbar; fehlende Metadaten werden dabei als `null` behandelt.
+Die Projektseite zeigt Verteilungen, Etagen und Räume als kompakte
+Bestandsübersichten; ihre versionierten Erstellwege öffnen beschriftete Modals
+statt dauerhafter Eingabezeilen. Projektgeräte werden als durchsuchbare,
+fünfspaltige Übersicht dargestellt. Manuelle Anlage, Übernahme aus der globalen
+Bibliothek und vollständige Bearbeitung erfolgen in einem gemeinsamen Modal.
+Die anschließende Vorschau verknüpfter Stromkreiszeilen bleibt davon getrennt,
+damit Änderungen weiterhin niemals still synchronisiert werden.
+`GET /api/projects/:projectId/export` verpackt denselben vollständigen
+Projektzustand in ein portables, format- und schema-versioniertes JSON-Dokument
+mit SHA-256-Prüfsumme. `POST /api/projects/:projectId/import` prüft Format,
+Snapshot-Relationen und Prüfsumme vor jedem Schreibzugriff. Der Modus `replace`
+läuft über `project.restore-state` und ist dadurch eine atomare, dauerhaft
+rückgängig machbare Projektrevision. Der Modus `duplicate` ordnet Projekt-,
+Struktur-, Geräte-, Raum-, Stromkreis- und Gerätezeilen-UUIDs vollständig neu
+zu und legt die Kopie mit Revision `0` in einer Transaktion an. Upgrade-only-
+Consumer-Verweise werden nicht in die Kopie übernommen; fachliche Verknüpfungen
+innerhalb des unterstützten Laufzeitmodells bleiben erhalten. Die
+Projektübersicht verwendet dafür den separaten Collection-Endpunkt
+`POST /api/projects/import`, der ausschließlich eine neue Kopie anlegt und
+deshalb weder eine bestehende Projekt-ID noch `expectedRevision` annimmt. Das
+Ersetzen eines Projekts bleibt auf dessen Einstellungsmodal und den
+projektgebundenen Endpunkt beschränkt.
 `distribution-board.insert` versioniert die Anlage einer Verteilung als einen
 vollständigen Block aus Verteilung, Stromkreisliste und vier Standardbereichen.
 Alle UUIDs entstehen vor dem Command und bleiben über Undo/Redo stabil.
 `distribution-board.delete` ist die persistierte Inverse und entfernt nur den
 vollständig unveränderten, weiterhin stromkreislosen Block. Controller und
 Projektseite übergeben die erwartete Projektrevision; der frühere direkte
-Controller-Schreibweg ist entfernt.
+Controller-Schreibweg ist entfernt. Verteilungen besitzen eine optionale
+Etagenreferenz sowie eine Netzart aus dem Projektkatalog. Anlage und
+nachträgliche Bearbeitung prüfen die Projektzugehörigkeit der Etage und die
+Freigabe der Netzart in den Projekteinstellungen.
+`distribution-board.update` versioniert Etage, Netzart und den
+verteilerweiten Gleichzeitigkeitsfaktor gemeinsam und stellt alle Werte über
+dauerhaftes Undo/Redo wieder her. Der Faktor liegt zwischen `0` und `1` und
+ist für bestehende sowie neu angelegte Verteilungen standardmäßig `1`.
+Snapshot-Schema 6 und der portable Projekttransfer enthalten diesen Wert;
+Schema 5 und älter werden mit dem neutralen Faktor `1` hochgestuft.
+Snapshot-Schema 4 enthält bereits Etage und Netzart; Schema 1/2 sowie
+gespeicherte Version-1-Strukturcommands werden ohne erfundene Zuordnung
+hochgestuft. Snapshot-Schema 3 wird mit allen sechs Netzarten als
+Projektauswahl hochgestuft.
 `project-floor.insert` und `project-room.insert` versionieren die Anlage von
 Geschossen und Räumen mit stabilen UUIDs. Die vollständigen Datensätze bilden
 jeweils die persistierte Inverse für Undo/Redo. Ein Geschoss wird durch Undo nur
-entfernt, solange ihm kein Raum zugeordnet wurde. Ein Raum wird nur entfernt,
+entfernt, solange ihm weder ein Raum noch eine Verteilung zugeordnet wurde. Ein
+Raum wird nur entfernt,
 solange weder eine CircuitDeviceRow noch ein aufbewahrter Upgrade-Datensatz auf
 ihn verweist. Beide POST-Endpunkte verlangen `expectedRevision`, liefern den
 aktualisierten Historienstand und besitzen keinen direkten Create-Schreibweg

docs/project-history-and-external-model-architecture.md

@@ -265,7 +265,9 @@ Completed foundation:
   snapshots in the same transaction
 - `project.update-settings` persists both project voltage defaults, its exact
   inverse, revision and history transition atomically; the project page and
-  existing PUT route require the current expected revision
+  existing PUT route require the current expected revision; the same
+  transaction derives every project-device and circuit voltage again, so
+  Undo/Redo cannot leave mixed voltage states
 - `distribution-board.insert` persists the complete generated board, circuit
   list and default-section structure with stable ids; its delete inverse
   refuses changed or populated structures and the project-page POST tracks the

docs/revit-requirements-llm-context.md

@@ -0,0 +1,269 @@
+# Kontext für die Revit-Anforderungsplanung
+
+## Zweck dieser Datei
+
+Diese Datei ist eine kompakte Übergabe an ein anderes LLM. Sie soll dabei
+helfen, gemeinsam mit dem Anwender die fachlichen und technischen Anforderungen
+für einen zukünftigen Revit-Datenaustausch zu klären.
+
+Die Revit-Schnittstelle ist **noch nicht implementiert**. Das LLM soll zunächst
+den tatsächlichen Arbeitsablauf erfragen, Unklarheiten sichtbar machen und
+daraus eine neue, überprüfbare Arbeitsanweisung erstellen. Es soll weder ein
+Dateiformat noch ein Datenbankschema oder eine UI ungefragt festlegen.
+
+## Produkt und fachliches Modell
+
+Leistungsbilanz ist eine Webanwendung für die elektrische Ausführungsplanung.
+Ihr Kern ist ein tabellenähnlicher Stromkreislisten-Editor für Verteilungen.
+
+Das unterstützte Laufzeitmodell ist:
+
+```text
+Project
+├── Floor
+│   └── Room
+├── ProjectDevice
+└── DistributionBoard
+    └── CircuitList
+        └── CircuitSection
+            └── Circuit
+                └── CircuitDeviceRow
+```
+
+Wichtige fachliche Grenzen:
+
+- Ein `Circuit` ist nicht dasselbe wie eine Gerätezeile.
+- Ein Stromkreis kann null, eine oder mehrere `CircuitDeviceRow` enthalten.
+- BMK (`equipmentIdentifier`), Schutz- und Kabeldaten gehören zum Stromkreis.
+- Menge, Einzelleistung, Gleichzeitigkeitsfaktor, cosPhi, Raum, Kostengruppe
+  und Kategorie gehören zur Gerätezeile.
+- Ein `ProjectDevice` ist eine wiederverwendbare, projektbezogene Vorlage.
+- Eine Gerätezeile kann mit einem Projektgerät verknüpft sein, behält aber
+  lokale Werte und ausdrücklich erfasste Abweichungen.
+- Änderungen eines Projektgeräts überschreiben verknüpfte Zeilen niemals
+  automatisch. Eine Synchronisierung benötigt Vorschau und Benutzerauswahl.
+- Manuelle, nicht mit einem Projektgerät verknüpfte Gerätezeilen sind regulär
+  erlaubt.
+- Bestehende BMKs und stabile UUIDs dürfen nicht automatisch verändert werden.
+- Neunummerierung ist immer eine ausdrückliche Benutzeraktion.
+- `IFCGUID` darf nicht als BMK oder als Ersatz für eine interne UUID verwendet
+  werden.
+
+Für einen späteren Revit-Austausch besonders relevante Daten sind:
+
+- Projekt: Name, interne/externe Projektnummer, Bauherr, Beschreibung,
+  Projektspannungen.
+- Geschoss und Raum: interne UUID, Name beziehungsweise Raumnummer und
+  Raumname.
+- Verteilung: interne UUID, Name, Etage, Netzart und Gleichzeitigkeitsfaktor.
+- Stromkreis: interne UUID, BMK, Anzeigename, Bereich, Schutz-, Kabel-,
+  Spannungs-, Steuerungs-, Status- und Bemerkungsdaten.
+- Gerätezeile: interne UUID, optionale Projektgeräteverknüpfung, Name,
+  Anzeigename, Phasenart, Anschlussart, Kostengruppe, Kategorie, Geschoss,
+  Raum, Menge, Einzelleistung, Gleichzeitigkeitsfaktor, cosPhi und Bemerkung.
+- Projektgerät: interne UUID sowie die wiederverwendbaren Gerätewerte.
+
+Die Phasenart ist fachlich `1-phasig` oder `3-phasig`. Die Spannung wird daraus
+und aus den Projekteinstellungen abgeleitet; freie Sonderspannungen sind im
+aktuellen Produkt nicht vorgesehen.
+
+## Aktuelle technische Architektur
+
+- Frontend: Next.js App Router, React und TypeScript unter `src/app` und
+  `src/frontend`.
+- API: Express und Zod unter `src/server`.
+- Fachregeln und typisierte Commands: `src/domain`.
+- Persistenz: SQLite, Drizzle und Repository-Adapter unter `src/db`.
+- Laufzeitkomposition konkreter Repositories:
+  `src/server/composition`.
+- Lokaler Betrieb: Browser/Next.js auf Port 3001, Express-API auf Port 3000,
+  SQLite-Datei unter `data/leistungsbilanz.db`.
+- Docker Compose wird für die lokale Entwicklung unterstützt.
+- PostgreSQL und Mehrbenutzerbetrieb sind noch nicht umgesetzt.
+
+Der zentrale Editor liegt unter:
+
+```text
+src/app/projects/[projectId]/circuit-lists/[circuitListId]/tree-edit/page.tsx
+src/frontend/components/circuit-tree-editor.tsx
+```
+
+Frontend-Aktionen werden als validierte API-Commands ausgeführt. Fachregeln
+liegen in Domain-Services; konkrete SQLite-Zugriffe bleiben in
+Persistenzadaptern. Neue Revit-Fachlogik darf deshalb nicht direkt von
+`better-sqlite3`, React-Komponenten oder globalen Datenbankinstanzen abhängen.
+
+## Revisionen, Undo/Redo und Sicherungspunkte
+
+Alle normalen projektbezogenen Änderungen laufen über eine gemeinsame
+Command- und Transaktionsgrenze:
+
+```text
+Fachänderung + inverses Kommando + Revision + Undo/Redo-Übergang
+```
+
+Diese Bestandteile werden atomar geschrieben oder vollständig zurückgerollt.
+Jedes Projekt besitzt eine monoton steigende `currentRevision`. Schreibbefehle
+geben die erwartete Revision mit, damit veraltete Clients keine neueren
+Änderungen überschreiben.
+
+Undo/Redo ist projektweit persistent und funktioniert nach Reload oder
+Anwendungsneustart. Zusätzlich gibt es:
+
+- eine unveränderliche Revisions-Timeline;
+- benannte und automatische logische Projektsnapshots;
+- wiederherstellbare Snapshots mit Prüfsumme;
+- einen portablen, versionierten JSON-Projekttransfer.
+
+Ein angewendeter Revit-Import muss später dieselbe Integritätsgrenze verwenden:
+Die bestätigten Änderungen sollen als ein nachvollziehbarer Projekt-Command
+beziehungsweise als ein fachlich definierter Änderungssatz atomar,
+revisioniert und rückgängig machbar sein.
+
+## Klare Abgrenzung zum vorhandenen JSON-Projekttransfer
+
+Der vorhandene JSON-Export/-Import überträgt den vollständigen internen
+Projektzustand. Er dient Sicherung, Wiederherstellung und Duplizierung eines
+Projekts innerhalb von Leistungsbilanz.
+
+Dieser Projekttransfer ist **kein** Revit-Austauschformat. Er enthält interne
+Strukturen und UUIDs und soll nicht ohne bewusste Entscheidung als Grundlage
+für CSV-Dateien oder Revit-Parameter verwendet werden.
+
+Der zukünftige Revit-Workflow soll dagegen externe Modellobjekte anhand stabiler
+externer Identitäten wiedererkennen, ausgewählte Planungswerte zuordnen und
+Ergebnisse so exportieren, dass Revit sie wieder den richtigen Objekten
+zuweisen kann.
+
+## Bereits vereinbarte Leitplanken für den externen Modellaustausch
+
+Diese Punkte gelten als Architekturvorgaben, noch nicht als fertiges
+Implementierungsdesign:
+
+- Ein Import schreibt niemals ungeprüft direkt in Stromkreise oder
+  Gerätezeilen.
+- Eingelesene Daten landen zuerst in einem Staging-/Vorschaubereich.
+- Vor der Übernahme werden neue, geänderte, fehlende, doppelte und
+  widersprüchliche Objekte angezeigt.
+- Wiederholte Importe müssen Objekte deterministisch anhand der externen Quelle
+  und einer stabilen Identität, voraussichtlich IFCGUID, erkennen.
+- Die Eindeutigkeit einer IFCGUID ist mindestens auf Projekt und externe
+  Modellquelle begrenzt; die genaue Quellendefinition ist noch zu klären.
+- Importierte Quellwerte und lokal in Leistungsbilanz geplante Werte müssen
+  unterscheidbar bleiben.
+- Lokale Planungswerte dürfen niemals still überschrieben werden.
+- Verknüpfungen zwischen externen Objekten und internen Fachobjekten müssen
+  ausdrücklich modelliert werden.
+- Fehlende oder widersprüchliche Identitäten werden gemeldet und niemals
+  automatisch einem anderen Objekt zugeordnet.
+- Ein Export bewahrt IFCGUID und erforderliche Quellidentitäten, damit Revit
+  die Werte deterministisch zurückschreiben kann.
+- Ein Export bezieht sich auf eine bekannte Projektrevision.
+- Große Datenmengen allein erzwingen noch keinen Wechsel von SQLite zu
+  PostgreSQL. PostgreSQL wird relevant bei Mehrbenutzerbetrieb, zentralem
+  Serverbetrieb oder unabhängigen Hintergrundjobs.
+
+Als mögliche, aber noch nicht beschlossene Konzepte wurden bisher genannt:
+
+- `ExternalModelSource`
+- `ExternalImportBatch`
+- `ExternalModelObject`
+- `ExternalObjectLink`
+- `ExternalParameterMapping`
+- `ExternalExportBatch`
+
+Diese Namen beschreiben Verantwortlichkeiten. Das andere LLM darf sie
+hinterfragen und verbessern, soll sie aber nicht als bereits vorhandene
+Tabellen behandeln.
+
+## Auftrag an das andere LLM
+
+Erarbeite die Anforderungen dialogorientiert mit dem Anwender. Beginne mit dem
+realen Ablauf in Revit und kläre danach schrittweise mindestens:
+
+1. Welche Revit-Objekte beziehungsweise Kategorien werden exportiert?
+2. Wie entsteht die Ausgangsdatei in Revit und wie sieht sie technisch aus
+   (CSV-Dialekt, Trennzeichen, Encoding, Dezimalformat, Kopfzeilen,
+   Revit-Versionen)?
+3. Welche Identitäten stehen zur Verfügung: IFCGUID, Revit `ElementId`,
+   Typ-ID, Modell-/Dateikennung oder weitere Schlüssel?
+4. Wie werden Hauptmodell, Teilmodelle, verknüpfte Modelle, Modellkopien und
+   aktualisierte Revit-Dateien unterschieden?
+5. Welche Parameter kommen aus Revit und welche Werte werden ausschließlich in
+   Leistungsbilanz geplant?
+6. Welche internen Ziele können externe Objekte erhalten: Projektgerät,
+   Gerätezeile, Stromkreis, Raum, Verteilung oder weitere Entitäten?
+7. Werden externe Objekte einzeln oder gesammelt einem Stromkreis,
+   Projektgerät, Raum oder einer Verteilung zugeordnet?
+8. Welche Werte sollen nach Revit zurückgeschrieben werden, in welchen
+   Einheiten und unter welchen Revit-Parameternamen?
+9. Muss die ursprüngliche Datei einschließlich unbekannter Spalten,
+   Zeilenreihenfolge und Formatierung erhalten werden, oder darf eine neue
+   Rückgabedatei erzeugt werden?
+10. Wie sollen Spalten-/Parametermappings erstellt, gespeichert,
+    wiederverwendet und zwischen Projekten geteilt werden?
+11. Was gilt bei erneutem Import für neue, geänderte, gelöschte, verschobene,
+    doppelte oder nicht mehr sichtbare Revit-Objekte?
+12. Wer gewinnt bei Konflikten zwischen neuem Revit-Wert und lokaler Änderung?
+    Welche Konflikte dürfen automatisch gelöst werden und welche benötigen
+    eine Auswahl?
+13. Welche Vorschau, Filter, Sammelaktionen und Bestätigungen benötigt der
+    Anwender vor der Übernahme?
+14. Welche fachlichen Validierungen und Pflichtfelder müssen eine Übernahme
+    verhindern oder nur eine Warnung erzeugen?
+15. Welche Dateigrößen, Objektzahlen und Laufzeiten sind realistisch?
+16. Müssen Import und Export synchron im Browser laufen oder werden später
+    Hintergrundjobs benötigt?
+17. Welche Informationen müssen für Nachvollziehbarkeit, Undo/Redo,
+    Versionshistorie und Support gespeichert werden?
+18. Welche konkreten End-to-End-Beispiele und Fehlerfälle dienen als
+    Abnahmekriterien?
+
+Stelle Rückfragen in kleinen, zusammenhängenden Blöcken. Unterscheide in deinen
+Notizen ausdrücklich:
+
+- vom Anwender bestätigte Anforderungen;
+- sinnvolle Vorschläge;
+- offene Entscheidungen;
+- technische Folgerungen;
+- bewusst nicht betrachtete spätere Ausbaustufen.
+
+## Erwartetes Ergebnis der Anforderungsrunde
+
+Erstelle am Ende eine neue Arbeitsanweisung für das implementierende LLM. Sie
+soll mindestens enthalten:
+
+- Ziel, Umfang und ausdrücklich ausgeschlossene Funktionen;
+- vollständigen Anwenderworkflow für Erstimport, Zuordnung, Folgeimport und
+  Rückexport;
+- vereinbartes Dateiformat mit einem anonymisierten Beispiel;
+- Feld- und Einheitenmapping einschließlich Richtung und Datenhoheit;
+- Identitäts-, Matching- und Quellmodell;
+- Regeln für neue, geänderte, fehlende und doppelte Objekte;
+- Konflikt-, Validierungs- und Freigaberegeln;
+- UI-Ablauf für Staging, Vorschau, Zuordnung und Bestätigung;
+- Anforderungen an Revision, Atomarität, Undo/Redo und Audit;
+- vorgeschlagene Modul- und Persistenzgrenzen, ohne bestehende
+  Architekturregeln zu umgehen;
+- schrittweise Implementierungsphasen mit überprüfbaren Abnahmekriterien;
+- offene Punkte, die vor dem jeweiligen Implementierungsschritt geklärt werden
+  müssen.
+
+Die Arbeitsanweisung soll noch keinen Code enthalten. Sie muss klar markieren,
+welche Entscheidungen der Anwender tatsächlich getroffen hat und welche Teile
+nur Architekturvorschläge des LLM sind.
+
+## Weiterführende Projektdokumente
+
+- `AGENTS.md` – verbindliche Domänen- und Implementierungsregeln
+- `docs/current-architecture.md` – vollständiger aktueller Laufzeit- und
+  Command-Pfad
+- `docs/project-history-and-external-model-architecture.md` – bisherige
+  Zukunftsrichtung für Versionierung, externes Modell und PostgreSQL
+- `docs/spec/01-domain-context.md` – fachlicher Kontext
+- `docs/spec/03-data-model-concept.md` – Datenmodellkonzept
+- `docs/spec/05-linked-devices-and-sync.md` – Regeln für Projektgeräte und
+  kontrollierte Synchronisierung
+- `docs/spec/07-implementation-phases-todo.md` – Roadmap, insbesondere Phase 13
+- `docs/circuit-list-editor-known-limitations.md` – noch nicht implementierte
+  Funktionen

docs/spec/08-current-product-backlog.md

@@ -0,0 +1,94 @@
+# Current Product Backlog
+
+This document records the next agreed product improvements. It describes
+requirements and intended sequencing, not proof of implementation.
+
+## Circuit List Editor
+
+- Collect the remaining editor interaction issues before changing additional
+  behavior.
+
+## First Release Baseline
+
+Complete this immediately before the first supported release, once the schema
+and initial feature set are frozen:
+
+- Decide explicitly whether pre-release databases, portable JSON exports,
+  logical snapshots and persisted command histories remain supported.
+- Create one clean baseline migration that builds the complete release schema
+  on an empty database.
+- Replace the active development migration chain and Drizzle metadata only if
+  no released installation depends on it.
+- Remove upgrade-only database, snapshot and command compatibility code only
+  for formats that are explicitly declared unsupported.
+- Preserve the pre-release migration history in Git history or a release tag.
+- Verify installation, migrations, application startup and core workflows
+  against a completely empty database.
+- Mark the resulting compatibility boundary with the first release tag.
+- Treat every migration published after that release as immutable.
+
+## Project History
+
+- [x] Every listed logical snapshot, including automatic snapshots, must be
+  explicitly restorable from the project history UI.
+- [x] Show which project change produced a snapshot. Prefer immutable revision
+  metadata over storing a second free-form description of the same change.
+- [x] Keep restoration auditable as a new project revision and preserve persistent
+  undo/redo.
+
+## Distribution Boards
+
+- [x] Assign an optional project floor to a distribution board.
+- [x] Store a supply classification for each distribution board:
+  - `AV` (Allgemeine Stromversorgung)
+  - `SV` (Sicherheitsstromversorgung)
+  - `EV` (Ersatzstromversorgung)
+  - `USV` (Unterbrechungsfreie Stromversorgung)
+  - `MSR` (Mess-, Steuerungs- und Regelungstechnik)
+  - `SiBe` (Sicherheitsbeleuchtung)
+- [x] Let project settings select which catalog supply types are used in a
+  project. Distribution-board dialogs offer only that selection; a type in
+  use cannot be disabled.
+- [x] Include both fields in project snapshots and portable project
+  export/import.
+- [x] Persist changes through project commands so they remain undoable after a
+  restart.
+
+## Device Voltage Derivation
+
+- [x] Derive voltage from the selected phase type and the project settings:
+  - single-phase uses the project's single-phase voltage;
+  - three-phase uses the project's three-phase voltage.
+- [x] Voltage is not editable on global devices, project devices or circuits.
+  Global devices store only their phase; copying one into a project derives
+  the target project's voltage.
+- [x] Project-device voltage follows its phase. Circuit voltage follows the
+  section phase; an unassigned circuit is three-phase only when all assigned
+  device rows with a valid phase are three-phase.
+- [x] Changing project voltage settings updates all project devices and circuits
+  atomically in the same persistent Undo/Redo step.
+- [x] Database migration `0019` and snapshot schema version `5` normalize older
+  stored values. Version-four and older imports remain supported and are
+  normalized while being upgraded.
+
+## Circuit List Power Summary
+
+- [x] Show the total power of every circuit section.
+- [x] Show the unadjusted total power of the complete distribution board.
+- [x] Store a distribution-board simultaneity factor between zero and one in
+  the distribution-board settings.
+- [x] Show the distribution-board total after applying that factor.
+- [x] Preserve the factor in project commands, snapshots and portable project
+  transfers.
+- [x] Keep column visibility and order as a project-specific UI preference so
+  all distribution boards in the same project open with the same columns.
+
+## Recommended Sequence
+
+1. [x] Distribution-board floor and supply fields.
+2. [x] Device voltage derivation without overrides.
+3. [x] Snapshot-to-revision descriptions and history presentation.
+4. [x] Distribution-board power summary and project column layout.
+
+The Revit/CSV/IFCGUID round-trip remains a separate jointly planned phase and
+must not be inferred from these tasks.

package.json

@@ -15,8 +15,8 @@
     "build:web": "next build",
     "typecheck:scripts": "tsc --noEmit -p tsconfig.scripts.json",
     "start": "node dist/server/index.js",
-    "test": "tsx --test tests/project-device-schema.test.ts tests/project-device-schema-migration.test.ts tests/project-device-placement.service.test.ts tests/project-device-sync.service.test.ts tests/legacy-consumer-migration-planner.test.ts tests/legacy-consumer-migration.service.test.ts tests/legacy-consumer-migration.repository.test.ts tests/circuit-numbering.service.test.ts tests/circuit-power-calculation.test.ts tests/circuit-tree.controller.test.ts tests/circuit-editor-history.test.ts tests/circuit-grid-insertion.test.ts tests/circuit-grid-safety.test.ts tests/circuit-grid-model.test.ts tests/circuit-structure-command.test.ts tests/circuit-device-row-move-command.test.ts tests/circuit-section-reorder-command.test.ts tests/circuit-section-renumber-command.test.ts tests/circuit-grid-projection.test.ts tests/distribution-board-structure-project-command.repository.test.ts tests/project-location-structure-project-command.repository.test.ts tests/project-device-project-command.repository.test.ts tests/project-device-structure-project-command.repository.test.ts tests/project-device-row-sync-project-command.repository.test.ts tests/circuit-section-reorder-project-command.repository.test.ts tests/circuit-section-renumber-project-command.repository.test.ts tests/project-command.model.test.ts tests/project-revision.persistence.test.ts tests/circuit-project-command.repository.test.ts tests/circuit-structure-project-command.repository.test.ts tests/circuit-device-row-project-command.repository.test.ts tests/circuit-device-row-structure-project-command.repository.test.ts tests/circuit-device-row-move-project-command.repository.test.ts tests/project-history.repository.test.ts tests/project-history-timeline.test.ts tests/project-version-history.test.ts tests/project-settings-project-command.repository.test.ts tests/project-state-snapshot.test.ts tests/project-snapshot-policy.test.ts tests/project-snapshot.repository.test.ts tests/project-state-restore-command.repository.test.ts tests/project-command.service.test.ts tests/database-backup.test.ts",
+    "test": "tsx --test tests/project-device-schema.test.ts tests/project-device-schema-migration.test.ts tests/project-device-placement.service.test.ts tests/project-device-sync.service.test.ts tests/legacy-consumer-migration-planner.test.ts tests/legacy-consumer-migration.service.test.ts tests/legacy-consumer-migration.repository.test.ts tests/circuit-numbering.service.test.ts tests/circuit-power-calculation.test.ts tests/circuit-tree.controller.test.ts tests/circuit-editor-history.test.ts tests/circuit-grid-insertion.test.ts tests/circuit-grid-safety.test.ts tests/circuit-grid-model.test.ts tests/circuit-structure-command.test.ts tests/circuit-device-row-move-command.test.ts tests/circuit-section-reorder-command.test.ts tests/circuit-section-renumber-command.test.ts tests/circuit-grid-projection.test.ts tests/distribution-board-structure-project-command.repository.test.ts tests/project-location-structure-project-command.repository.test.ts tests/project-device-project-command.repository.test.ts tests/project-device-structure-project-command.repository.test.ts tests/project-device-row-sync-project-command.repository.test.ts tests/circuit-section-reorder-project-command.repository.test.ts tests/circuit-section-renumber-project-command.repository.test.ts tests/project-command.model.test.ts tests/project-revision.persistence.test.ts tests/circuit-project-command.repository.test.ts tests/circuit-structure-project-command.repository.test.ts tests/circuit-device-row-project-command.repository.test.ts tests/circuit-device-row-structure-project-command.repository.test.ts tests/circuit-device-row-move-project-command.repository.test.ts tests/project-history.repository.test.ts tests/project-history-timeline.test.ts tests/project-version-history.test.ts tests/project-overview-import.test.ts tests/project-settings-project-command.repository.test.ts tests/project-state-snapshot.test.ts tests/project-snapshot-policy.test.ts tests/project-snapshot.repository.test.ts tests/project-state-restore-command.repository.test.ts tests/project-command.service.test.ts tests/database-backup.test.ts",
-    "test:watch": "tsx --watch --test tests/project-device-schema.test.ts tests/project-device-schema-migration.test.ts tests/project-device-placement.service.test.ts tests/project-device-sync.service.test.ts tests/legacy-consumer-migration-planner.test.ts tests/legacy-consumer-migration.service.test.ts tests/legacy-consumer-migration.repository.test.ts tests/circuit-numbering.service.test.ts tests/circuit-power-calculation.test.ts tests/circuit-tree.controller.test.ts tests/circuit-editor-history.test.ts tests/circuit-grid-insertion.test.ts tests/circuit-grid-safety.test.ts tests/circuit-grid-model.test.ts tests/circuit-structure-command.test.ts tests/circuit-device-row-move-command.test.ts tests/circuit-section-reorder-command.test.ts tests/circuit-section-renumber-command.test.ts tests/circuit-grid-projection.test.ts tests/distribution-board-structure-project-command.repository.test.ts tests/project-location-structure-project-command.repository.test.ts tests/project-device-project-command.repository.test.ts tests/project-device-structure-project-command.repository.test.ts tests/project-device-row-sync-project-command.repository.test.ts tests/circuit-section-reorder-project-command.repository.test.ts tests/circuit-section-renumber-project-command.repository.test.ts tests/project-command.model.test.ts tests/project-revision.persistence.test.ts tests/circuit-project-command.repository.test.ts tests/circuit-structure-project-command.repository.test.ts tests/circuit-device-row-project-command.repository.test.ts tests/circuit-device-row-structure-project-command.repository.test.ts tests/circuit-device-row-move-project-command.repository.test.ts tests/project-history.repository.test.ts tests/project-history-timeline.test.ts tests/project-version-history.test.ts tests/project-settings-project-command.repository.test.ts tests/project-state-snapshot.test.ts tests/project-snapshot-policy.test.ts tests/project-snapshot.repository.test.ts tests/project-state-restore-command.repository.test.ts tests/project-command.service.test.ts tests/database-backup.test.ts",
+    "test:watch": "tsx --watch --test tests/project-device-schema.test.ts tests/project-device-schema-migration.test.ts tests/project-device-placement.service.test.ts tests/project-device-sync.service.test.ts tests/legacy-consumer-migration-planner.test.ts tests/legacy-consumer-migration.service.test.ts tests/legacy-consumer-migration.repository.test.ts tests/circuit-numbering.service.test.ts tests/circuit-power-calculation.test.ts tests/circuit-tree.controller.test.ts tests/circuit-editor-history.test.ts tests/circuit-grid-insertion.test.ts tests/circuit-grid-safety.test.ts tests/circuit-grid-model.test.ts tests/circuit-structure-command.test.ts tests/circuit-device-row-move-command.test.ts tests/circuit-section-reorder-command.test.ts tests/circuit-section-renumber-command.test.ts tests/circuit-grid-projection.test.ts tests/distribution-board-structure-project-command.repository.test.ts tests/project-location-structure-project-command.repository.test.ts tests/project-device-project-command.repository.test.ts tests/project-device-structure-project-command.repository.test.ts tests/project-device-row-sync-project-command.repository.test.ts tests/circuit-section-reorder-project-command.repository.test.ts tests/circuit-section-renumber-project-command.repository.test.ts tests/project-command.model.test.ts tests/project-revision.persistence.test.ts tests/circuit-project-command.repository.test.ts tests/circuit-structure-project-command.repository.test.ts tests/circuit-device-row-project-command.repository.test.ts tests/circuit-device-row-structure-project-command.repository.test.ts tests/circuit-device-row-move-project-command.repository.test.ts tests/project-history.repository.test.ts tests/project-history-timeline.test.ts tests/project-version-history.test.ts tests/project-overview-import.test.ts tests/project-settings-project-command.repository.test.ts tests/project-state-snapshot.test.ts tests/project-snapshot-policy.test.ts tests/project-snapshot.repository.test.ts tests/project-state-restore-command.repository.test.ts tests/project-command.service.test.ts tests/database-backup.test.ts",
     "db:generate": "drizzle-kit generate",
     "db:migrate": "drizzle-kit migrate",
     "db:backup": "tsx scripts/db-backup.ts",

scripts/db-verify-circuit-schema.js

@@ -48,12 +48,45 @@ const circuitColumns = new Set(
   db.prepare("PRAGMA table_info(circuits)").all().map((column) => column.name)
 );
 const missingCircuitColumns = requiredCircuitColumns.filter((name) => !circuitColumns.has(name));
+const requiredProjectColumns = [
+  "internal_project_number",
+  "external_project_number",
+  "building_owner",
+  "description",
+  "enabled_distribution_board_supply_types",
+];
+const projectColumns = new Set(
+  db.prepare("PRAGMA table_info(projects)").all().map((column) => column.name)
+);
+const missingProjectColumns = requiredProjectColumns.filter(
+  (name) => !projectColumns.has(name)
+);
+const requiredDistributionBoardColumns = ["floor_id", "supply_type"];
+const distributionBoardColumns = new Set(
+  db
+    .prepare("PRAGMA table_info(distribution_boards)")
+    .all()
+    .map((column) => column.name)
+);
+const missingDistributionBoardColumns =
+  requiredDistributionBoardColumns.filter(
+    (name) => !distributionBoardColumns.has(name)
+  );
+const integrityCheck = db.pragma("integrity_check", { simple: true });
+const foreignKeyViolations = db.pragma("foreign_key_check");
 
 console.log("Database:", dbPath);
 console.log("Required tables:", requiredTables.join(", "));
 console.log("Existing tables:", [...existing].join(", ") || "(none)");
 console.log("Required project-device columns:", requiredProjectDeviceColumns.join(", "));
 console.log("Required circuit columns:", requiredCircuitColumns.join(", "));
+console.log("Required project columns:", requiredProjectColumns.join(", "));
+console.log(
+  "Required distribution-board columns:",
+  requiredDistributionBoardColumns.join(", ")
+);
+console.log("Integrity:", integrityCheck);
+console.log("Foreign-key violations:", foreignKeyViolations.length);
 
 if (missing.length > 0) {
   console.error("Missing tables:", missing.join(", "));
@@ -78,4 +111,22 @@ if (missingCircuitColumns.length > 0) {
   process.exit(1);
 }
 
+if (missingProjectColumns.length > 0) {
+  console.error("Missing project columns:", missingProjectColumns.join(", "));
+  process.exit(1);
+}
+
+if (missingDistributionBoardColumns.length > 0) {
+  console.error(
+    "Missing distribution-board columns:",
+    missingDistributionBoardColumns.join(", ")
+  );
+  process.exit(1);
+}
+
+if (integrityCheck !== "ok" || foreignKeyViolations.length > 0) {
+  console.error("Database integrity or foreign-key verification failed.");
+  process.exit(1);
+}
+
 console.log("Circuit-first schema verification passed.");

src/app/globals.css

@@ -71,6 +71,13 @@ body {
   opacity: 0.45;
 }
 
+.editor-toolbar .project-device-drawer-toggle {
+  border-color: #2563eb;
+  background: #2563eb;
+  color: #fff;
+  font-weight: 600;
+}
+
 .active-view-summary {
   display: flex;
   flex-wrap: wrap;
@@ -109,6 +116,39 @@ body {
   font-weight: 600;
 }
 
+.distribution-power-summary {
+  display: grid;
+  grid-template-columns: repeat(3, minmax(12rem, 1fr));
+  gap: 0.5rem;
+  padding: 0.55rem;
+  border: 1px solid #cbd5e1;
+  border-radius: 5px;
+  background: #f8fafc;
+}
+
+.distribution-power-summary > div {
+  display: flex;
+  flex-direction: column;
+  gap: 0.15rem;
+}
+
+.distribution-power-summary span {
+  color: #475569;
+  font-size: 0.74rem;
+  line-height: 1.2;
+}
+
+.distribution-power-summary strong {
+  color: #172033;
+  font-size: 0.95rem;
+}
+
+@media (max-width: 900px) {
+  .distribution-power-summary {
+    grid-template-columns: 1fr;
+  }
+}
+
 .column-settings-menu {
   position: absolute;
   z-index: 9;
@@ -271,12 +311,10 @@ body {
 }
 
 .tree-editor-layout {
-  display: grid;
+  display: block;
-  grid-template-columns: minmax(240px, 320px) minmax(0, 1fr);
-  gap: 0.75rem;
   min-height: 560px;
   min-width: 0;
-  align-items: start;
+  position: relative;
 }
 
 .project-device-sidebar {
@@ -354,7 +392,7 @@ body {
 
 .tree-grid {
   width: max-content;
-  min-width: 100%;
+  min-width: 0;
   border-collapse: collapse;
   font-size: 0.9rem;
 }
@@ -362,37 +400,50 @@ body {
 .tree-grid th,
 .tree-grid td {
   border: 1px solid #e4e9f2;
-  padding: 0.35rem 0.5rem;
+  padding: 0.35rem 0.4rem;
-  white-space: nowrap;
   vertical-align: middle;
 }
 
 .tree-grid th {
+  width: 1px;
   background: #f4f7fb;
   position: sticky;
   top: 0;
   z-index: 2;
   vertical-align: top;
+  white-space: normal;
+}
+
+.tree-grid td {
+  white-space: nowrap;
 }
 
 .tree-grid .header-cell {
   display: flex;
-  align-items: center;
+  flex-direction: column;
-  gap: 0.3rem;
+  align-items: stretch;
+  gap: 0.2rem;
+  min-width: 0;
 }
 
 .tree-grid .header-filter-btn {
+  display: block;
+  width: 100%;
   border: 1px solid #c4cddc;
   background: #fff;
   border-radius: 3px;
   font-size: 0.75rem;
   padding: 0.15rem 0.35rem;
+  white-space: nowrap;
 }
 
 .tree-grid .header-sort-btn {
-  display: inline-flex;
+  display: flex;
   align-items: center;
+  justify-content: space-between;
   gap: 0.25rem;
+  width: 100%;
+  min-width: 0;
   border: 0;
   background: transparent;
   padding: 0;
@@ -400,10 +451,46 @@ body {
   font: inherit;
   font-size: 0.78rem;
   font-weight: 600;
+  line-height: 1.15;
+  overflow-wrap: anywhere;
+  white-space: normal;
   text-align: left;
   cursor: pointer;
 }
 
+.project-device-drawer {
+  position: fixed;
+  z-index: 1040;
+  top: 5.5rem;
+  right: 1rem;
+  left: auto;
+  width: min(360px, calc(100vw - 2rem));
+  max-height: calc(100vh - 7rem);
+  overflow: auto;
+  border-radius: 0.5rem;
+  box-shadow: 0 0.75rem 2rem rgba(31, 41, 55, 0.22);
+}
+
+.project-device-drawer-header {
+  display: flex;
+  align-items: flex-start;
+  justify-content: space-between;
+  gap: 0.75rem;
+}
+
+.project-device-drawer-header span {
+  color: #6b7280;
+  font-size: 0.75rem;
+}
+
+.project-device-drawer-header button {
+  border: 1px solid #c4cddc;
+  background: #fff;
+  border-radius: 4px;
+  padding: 0.25rem 0.4rem;
+  font-size: 0.78rem;
+}
+
 .tree-grid .header-sort-btn:hover span:first-child,
 .tree-grid .header-sort-btn:focus-visible span:first-child {
   text-decoration: underline;
@@ -641,6 +728,18 @@ body {
   outline-offset: -2px;
 }
 
+.tree-grid .section-title {
+  display: flex;
+  align-items: baseline;
+  gap: 0.75rem;
+}
+
+.tree-grid .section-title span {
+  color: #475569;
+  font-size: 0.78rem;
+  font-weight: 500;
+}
+
 .tree-grid .cell-invalid {
   outline: 2px solid #c2410c;
   outline-offset: -2px;
@@ -651,7 +750,8 @@ body {
   border-color: #c2410c;
 }
 
-.tree-grid input {
+.tree-grid input,
+.tree-grid select {
   width: 100%;
   min-width: 5rem;
   border: 1px solid #9fb6e0;
@@ -783,8 +883,9 @@ body {
   margin: 0;
 }
 
-@media (max-width: 1200px) {
+@media (max-width: 720px) {
-  .tree-editor-layout {
+  .project-device-drawer {
-    grid-template-columns: 1fr;
+    top: 4.5rem;
+    max-height: calc(100vh - 5.5rem);
   }
 }

src/app/projects/[projectId]/circuit-lists/[circuitListId]/tree-edit/page.tsx

@@ -8,8 +8,8 @@ export default function CircuitTreeEditPage() {
   const params = useParams<{ projectId: string; circuitListId: string }>();
 
   return (
-    <main className="container py-4">
+    <main className="container-fluid px-3 px-xxl-4 py-4">
-      <div className="d-flex justify-content-between align-items-center mb-3">
+      <div className="d-flex flex-wrap justify-content-between align-items-center gap-3 mb-3">
         <div>
           <h1 className="h4 mb-1">Stromkreisliste</h1>
           <p className="text-secondary mb-0">Stromkreise und zugeordnete Geräte bearbeiten.</p>

src/app/projects/page.tsx

@@ -6,6 +6,7 @@ import {
   createGlobalDevice,
   createProject,
   deleteGlobalDevice,
+  importProjectTransferAsNew,
   listGlobalDevices,
   listProjects,
   updateGlobalDevice,
@@ -23,7 +24,6 @@ const emptyGlobalDevice: CreateGlobalDeviceInput = {
   quantity: 1,
   installedPowerPerUnitKw: 0.1,
   demandFactor: 1,
-  voltageV: 230,
   phaseCount: 1,
   powerFactor: 1,
   note: "",
@@ -48,13 +48,22 @@ export default function ProjectsPage() {
     quantity: "1",
     installedPowerPerUnitKw: "0.1",
     demandFactor: "1",
-    voltageV: "230",
     phaseCount: "1",
     powerFactor: "1",
     note: "",
   });
   const [isSaving, setIsSaving] = useState(false);
   const [error, setError] = useState<string | null>(null);
+  const [projectImport, setProjectImport] = useState<unknown>(null);
+  const [projectImportFilename, setProjectImportFilename] = useState("");
+  const [projectImportInputKey, setProjectImportInputKey] = useState(0);
+  const [projectImportFileError, setProjectImportFileError] = useState<
+    string | null
+  >(null);
+  const [importedProject, setImportedProject] = useState<{
+    projectId: string;
+    name: string;
+  } | null>(null);
 
   async function loadData() {
     setError(null);
@@ -87,6 +96,49 @@ export default function ProjectsPage() {
     }
   }
 
+  async function handleProjectImportFile(file: File | undefined) {
+    setProjectImport(null);
+    setProjectImportFilename("");
+    setProjectImportFileError(null);
+    setImportedProject(null);
+    if (!file) {
+      return;
+    }
+    try {
+      setProjectImport(JSON.parse(await file.text()) as unknown);
+      setProjectImportFilename(file.name);
+    } catch {
+      setProjectImportFileError(
+        "Die ausgewählte Datei enthält kein gültiges JSON."
+      );
+    }
+  }
+
+  async function handleImportProject() {
+    if (projectImport === null) {
+      return;
+    }
+    setIsSaving(true);
+    setError(null);
+    setImportedProject(null);
+    try {
+      const imported = await importProjectTransferAsNew(projectImport);
+      setProjects(await listProjects());
+      setImportedProject(imported);
+      setProjectImport(null);
+      setProjectImportFilename("");
+      setProjectImportInputKey((current) => current + 1);
+    } catch (err) {
+      setError(
+        err instanceof Error
+          ? err.message
+          : "Projektdatei konnte nicht importiert werden."
+      );
+    } finally {
+      setIsSaving(false);
+    }
+  }
+
   async function handleCreateGlobalDevice(event: FormEvent<HTMLFormElement>) {
     event.preventDefault();
     if (!globalDeviceForm.name.trim()) {
@@ -99,7 +151,6 @@ export default function ProjectsPage() {
       quantity: Number(globalDeviceForm.quantity),
       installedPowerPerUnitKw: Number(globalDeviceForm.installedPowerPerUnitKw),
       demandFactor: Number(globalDeviceForm.demandFactor),
-      voltageV: toOptionalNumber(globalDeviceForm.voltageV),
       phaseCount: globalDeviceForm.phaseCount === "3" ? 3 : 1,
       powerFactor: toOptionalNumber(globalDeviceForm.powerFactor),
       note: globalDeviceForm.note.trim() || undefined,
@@ -116,7 +167,6 @@ export default function ProjectsPage() {
         quantity: String(emptyGlobalDevice.quantity),
         installedPowerPerUnitKw: String(emptyGlobalDevice.installedPowerPerUnitKw),
         demandFactor: String(emptyGlobalDevice.demandFactor),
-        voltageV: String(emptyGlobalDevice.voltageV ?? ""),
         phaseCount: String(emptyGlobalDevice.phaseCount ?? 1),
         powerFactor: String(emptyGlobalDevice.powerFactor ?? ""),
         note: emptyGlobalDevice.note ?? "",
@@ -143,7 +193,7 @@ export default function ProjectsPage() {
 
   async function handleQuickUpdateGlobalDevice(
     device: GlobalDeviceDto,
-    key: "name" | "displayName" | "category",
+    key: "name" | "displayName" | "category" | "phaseCount",
     value: string
   ) {
     const payload: CreateGlobalDeviceInput = {
@@ -153,8 +203,12 @@ export default function ProjectsPage() {
       quantity: device.quantity,
       installedPowerPerUnitKw: device.installedPowerPerUnitKw,
       demandFactor: device.demandFactor,
-      voltageV: device.voltageV ?? undefined,
+      phaseCount:
-      phaseCount: device.phaseCount ?? undefined,
+        key === "phaseCount"
+          ? value === "3"
+            ? 3
+            : 1
+          : device.phaseCount ?? 1,
       powerFactor: device.powerFactor ?? undefined,
       note: device.note ?? undefined,
     };
@@ -179,7 +233,7 @@ export default function ProjectsPage() {
 
       <div className="row g-4">
         <section className="col-12 col-lg-4">
-          <div className="card shadow-sm">
+          <div className="card shadow-sm mb-4">
             <div className="card-header">Neues Projekt</div>
             <div className="card-body">
               <form className="vstack gap-3" onSubmit={handleCreateProject}>
@@ -198,6 +252,60 @@ export default function ProjectsPage() {
               </form>
             </div>
           </div>
+          <div className="card shadow-sm">
+            <div className="card-header">Projekt importieren</div>
+            <div className="card-body">
+              <p className="text-secondary small">
+                Eine exportierte JSON-Projektdatei wird als eigenständige Kopie
+                mit neuen internen IDs angelegt.
+              </p>
+              <label className="form-label" htmlFor="project-overview-import">
+                Projektdatei auswählen
+              </label>
+              <input
+                accept=".json,application/json"
+                className="form-control"
+                disabled={isSaving}
+                id="project-overview-import"
+                key={projectImportInputKey}
+                onChange={(event) =>
+                  void handleProjectImportFile(event.target.files?.[0])
+                }
+                type="file"
+              />
+              {projectImportFilename ? (
+                <div className="form-text">
+                  {projectImportFilename} ist bereit.
+                </div>
+              ) : null}
+              {projectImportFileError ? (
+                <div className="text-danger small mt-1">
+                  {projectImportFileError}
+                </div>
+              ) : null}
+              <button
+                className="btn btn-outline-primary mt-3 w-100"
+                disabled={isSaving || projectImport === null}
+                onClick={() => void handleImportProject()}
+                type="button"
+              >
+                Als neues Projekt importieren
+              </button>
+              {importedProject ? (
+                <div className="alert alert-success mt-3 mb-0">
+                  <div className="small mb-2">
+                    „{importedProject.name}“ wurde angelegt.
+                  </div>
+                  <Link
+                    className="btn btn-sm btn-success"
+                    href={`/projects/${importedProject.projectId}`}
+                  >
+                    Importiertes Projekt öffnen
+                  </Link>
+                </div>
+              ) : null}
+            </div>
+          </div>
         </section>
 
         <section className="col-12 col-lg-8">
@@ -313,8 +421,8 @@ export default function ProjectsPage() {
                   setGlobalDeviceForm((current) => ({ ...current, phaseCount: event.target.value }))
                 }
               >
-                <option value="1">1-ph</option>
+                <option value="1">1-phasig</option>
-                <option value="3">3-ph</option>
+                <option value="3">3-phasig</option>
               </select>
             </div>
             <div className="col-6 col-md-2">
@@ -334,6 +442,7 @@ export default function ProjectsPage() {
                 <th>Anzahl</th>
                 <th>Leistung je Stück [kW]</th>
                 <th>GZF</th>
+                <th>Phasenart</th>
                 <th>Aktion</th>
               </tr>
             </thead>
@@ -376,6 +485,23 @@ export default function ProjectsPage() {
                   <td>{device.quantity}</td>
                   <td>{device.installedPowerPerUnitKw}</td>
                   <td>{device.demandFactor}</td>
+                  <td>
+                    <select
+                      className="form-select form-select-sm"
+                      aria-label={`Phasenart für ${device.displayName}`}
+                      value={String(device.phaseCount ?? 1)}
+                      onChange={(event) =>
+                        void handleQuickUpdateGlobalDevice(
+                          device,
+                          "phaseCount",
+                          event.target.value
+                        )
+                      }
+                    >
+                      <option value="1">1-phasig</option>
+                      <option value="3">3-phasig</option>
+                    </select>
+                  </td>
                   <td>
                     <button
                       className="btn btn-sm btn-outline-danger"
@@ -389,7 +515,7 @@ export default function ProjectsPage() {
               ))}
               {!globalDevices.length ? (
                 <tr>
-                  <td colSpan={7} className="text-center text-secondary py-4">
+                  <td colSpan={8} className="text-center text-secondary py-4">
                     Noch keine globalen Geräte vorhanden.
                   </td>
                 </tr>

src/db/migrations/0016_dashing_darkstar.sql

@@ -0,0 +1,4 @@
+ALTER TABLE `projects` ADD `internal_project_number` text;--> statement-breakpoint
+ALTER TABLE `projects` ADD `external_project_number` text;--> statement-breakpoint
+ALTER TABLE `projects` ADD `building_owner` text;--> statement-breakpoint
+ALTER TABLE `projects` ADD `description` text;

src/db/migrations/0017_vengeful_romulus.sql

@@ -0,0 +1,2 @@
+ALTER TABLE `distribution_boards` ADD `floor_id` text REFERENCES floors(id);--> statement-breakpoint
+ALTER TABLE `distribution_boards` ADD `supply_type` text;

src/db/migrations/0018_fancy_argent.sql

@@ -0,0 +1 @@
+ALTER TABLE `projects` ADD `enabled_distribution_board_supply_types` text DEFAULT '["AV","SV","EV","USV","MSR","SiBe"]' NOT NULL;

src/db/migrations/0019_normalize_project_voltages.sql

@@ -0,0 +1,48 @@
+UPDATE `global_devices`
+SET `voltage_v` = NULL;
+--> statement-breakpoint
+UPDATE `project_devices` AS `pd`
+SET `voltage_v` = CASE
+  WHEN `pd`.`phase_type` = 'three_phase' THEN `p`.`three_phase_voltage_v`
+  ELSE `p`.`single_phase_voltage_v`
+END
+FROM `projects` AS `p`
+WHERE `p`.`id` = `pd`.`project_id`;
+--> statement-breakpoint
+WITH `derived_circuit_voltages` AS (
+  SELECT
+    `c`.`id` AS `circuit_id`,
+    CASE
+      WHEN `cs`.`key` = 'three_phase' THEN `p`.`three_phase_voltage_v`
+      WHEN `cs`.`key` IN ('lighting', 'single_phase') THEN `p`.`single_phase_voltage_v`
+      WHEN EXISTS (
+        SELECT 1
+        FROM `circuit_device_rows` AS `three_phase_row`
+        WHERE `three_phase_row`.`circuit_id` = `c`.`id`
+          AND `three_phase_row`.`phase_type` = 'three_phase'
+      ) AND NOT EXISTS (
+        SELECT 1
+        FROM `circuit_device_rows` AS `other_row`
+        WHERE `other_row`.`circuit_id` = `c`.`id`
+          AND `other_row`.`phase_type` = 'single_phase'
+      ) THEN `p`.`three_phase_voltage_v`
+      ELSE `p`.`single_phase_voltage_v`
+    END AS `derived_voltage`
+  FROM `circuits` AS `c`
+  INNER JOIN `circuit_lists` AS `cl`
+    ON `cl`.`id` = `c`.`circuit_list_id`
+  INNER JOIN `projects` AS `p`
+    ON `p`.`id` = `cl`.`project_id`
+  INNER JOIN `circuit_sections` AS `cs`
+    ON `cs`.`id` = `c`.`section_id`
+)
+UPDATE `circuits`
+SET `voltage` = (
+  SELECT `derived_voltage`
+  FROM `derived_circuit_voltages`
+  WHERE `circuit_id` = `circuits`.`id`
+)
+WHERE `id` IN (
+  SELECT `circuit_id`
+  FROM `derived_circuit_voltages`
+);

src/db/migrations/0020_normalize_phase_types.sql

@@ -0,0 +1,85 @@
+UPDATE `project_devices`
+SET `phase_type` = CASE
+  WHEN LOWER(REPLACE(REPLACE(TRIM(`phase_type`), '-', ''), '_', ''))
+    IN ('1ph', '1phase', '1phasig', 'einphasig', 'singlephase')
+    THEN 'single_phase'
+  WHEN LOWER(REPLACE(REPLACE(TRIM(`phase_type`), '-', ''), '_', ''))
+    IN ('3ph', '3phase', '3phasig', 'dreiphasig', 'threephase')
+    THEN 'three_phase'
+  ELSE `phase_type`
+END
+WHERE LOWER(REPLACE(REPLACE(TRIM(`phase_type`), '-', ''), '_', ''))
+  IN (
+    '1ph',
+    '1phase',
+    '1phasig',
+    'einphasig',
+    'singlephase',
+    '3ph',
+    '3phase',
+    '3phasig',
+    'dreiphasig',
+    'threephase'
+  );
+--> statement-breakpoint
+UPDATE `circuit_device_rows`
+SET `phase_type` = CASE
+  WHEN LOWER(REPLACE(REPLACE(TRIM(`phase_type`), '-', ''), '_', ''))
+    IN ('1ph', '1phase', '1phasig', 'einphasig', 'singlephase')
+    THEN 'single_phase'
+  WHEN LOWER(REPLACE(REPLACE(TRIM(`phase_type`), '-', ''), '_', ''))
+    IN ('3ph', '3phase', '3phasig', 'dreiphasig', 'threephase')
+    THEN 'three_phase'
+  ELSE `phase_type`
+END
+WHERE LOWER(REPLACE(REPLACE(TRIM(`phase_type`), '-', ''), '_', ''))
+  IN (
+    '1ph',
+    '1phase',
+    '1phasig',
+    'einphasig',
+    'singlephase',
+    '3ph',
+    '3phase',
+    '3phasig',
+    'dreiphasig',
+    'threephase'
+  );
+--> statement-breakpoint
+WITH `derived_circuit_voltages` AS (
+  SELECT
+    `c`.`id` AS `circuit_id`,
+    CASE
+      WHEN `cs`.`key` = 'three_phase' THEN `p`.`three_phase_voltage_v`
+      WHEN `cs`.`key` IN ('lighting', 'single_phase') THEN `p`.`single_phase_voltage_v`
+      WHEN EXISTS (
+        SELECT 1
+        FROM `circuit_device_rows` AS `three_phase_row`
+        WHERE `three_phase_row`.`circuit_id` = `c`.`id`
+          AND `three_phase_row`.`phase_type` = 'three_phase'
+      ) AND NOT EXISTS (
+        SELECT 1
+        FROM `circuit_device_rows` AS `single_phase_row`
+        WHERE `single_phase_row`.`circuit_id` = `c`.`id`
+          AND `single_phase_row`.`phase_type` = 'single_phase'
+      ) THEN `p`.`three_phase_voltage_v`
+      ELSE `p`.`single_phase_voltage_v`
+    END AS `derived_voltage`
+  FROM `circuits` AS `c`
+  INNER JOIN `circuit_lists` AS `cl`
+    ON `cl`.`id` = `c`.`circuit_list_id`
+  INNER JOIN `projects` AS `p`
+    ON `p`.`id` = `cl`.`project_id`
+  INNER JOIN `circuit_sections` AS `cs`
+    ON `cs`.`id` = `c`.`section_id`
+)
+UPDATE `circuits`
+SET `voltage` = (
+  SELECT `derived_voltage`
+  FROM `derived_circuit_voltages`
+  WHERE `circuit_id` = `circuits`.`id`
+)
+WHERE `id` IN (
+  SELECT `circuit_id`
+  FROM `derived_circuit_voltages`
+);

src/db/migrations/0021_fill_missing_phase_types.sql

@@ -0,0 +1,75 @@
+UPDATE `circuit_device_rows`
+SET `phase_type` = COALESCE(
+  (
+    SELECT `pd`.`phase_type`
+    FROM `project_devices` AS `pd`
+    WHERE `pd`.`id` = `circuit_device_rows`.`linked_project_device_id`
+      AND `pd`.`phase_type` IN ('single_phase', 'three_phase')
+  ),
+  (
+    SELECT CASE
+      WHEN `cs`.`key` = 'three_phase' THEN 'three_phase'
+      WHEN `cs`.`key` IN ('lighting', 'single_phase') THEN 'single_phase'
+      ELSE NULL
+    END
+    FROM `circuits` AS `c`
+    INNER JOIN `circuit_sections` AS `cs`
+      ON `cs`.`id` = `c`.`section_id`
+    WHERE `c`.`id` = `circuit_device_rows`.`circuit_id`
+  )
+)
+WHERE `phase_type` IS NULL
+  AND (
+    EXISTS (
+      SELECT 1
+      FROM `project_devices` AS `pd`
+      WHERE `pd`.`id` = `circuit_device_rows`.`linked_project_device_id`
+        AND `pd`.`phase_type` IN ('single_phase', 'three_phase')
+    )
+    OR EXISTS (
+      SELECT 1
+      FROM `circuits` AS `c`
+      INNER JOIN `circuit_sections` AS `cs`
+        ON `cs`.`id` = `c`.`section_id`
+      WHERE `c`.`id` = `circuit_device_rows`.`circuit_id`
+        AND `cs`.`key` IN ('lighting', 'single_phase', 'three_phase')
+    )
+  );
+--> statement-breakpoint
+WITH `derived_circuit_voltages` AS (
+  SELECT
+    `c`.`id` AS `circuit_id`,
+    CASE
+      WHEN `cs`.`key` = 'three_phase' THEN `p`.`three_phase_voltage_v`
+      WHEN `cs`.`key` IN ('lighting', 'single_phase') THEN `p`.`single_phase_voltage_v`
+      WHEN EXISTS (
+        SELECT 1
+        FROM `circuit_device_rows` AS `three_phase_row`
+        WHERE `three_phase_row`.`circuit_id` = `c`.`id`
+          AND `three_phase_row`.`phase_type` = 'three_phase'
+      ) AND NOT EXISTS (
+        SELECT 1
+        FROM `circuit_device_rows` AS `single_phase_row`
+        WHERE `single_phase_row`.`circuit_id` = `c`.`id`
+          AND `single_phase_row`.`phase_type` = 'single_phase'
+      ) THEN `p`.`three_phase_voltage_v`
+      ELSE `p`.`single_phase_voltage_v`
+    END AS `derived_voltage`
+  FROM `circuits` AS `c`
+  INNER JOIN `circuit_lists` AS `cl`
+    ON `cl`.`id` = `c`.`circuit_list_id`
+  INNER JOIN `projects` AS `p`
+    ON `p`.`id` = `cl`.`project_id`
+  INNER JOIN `circuit_sections` AS `cs`
+    ON `cs`.`id` = `c`.`section_id`
+)
+UPDATE `circuits`
+SET `voltage` = (
+  SELECT `derived_voltage`
+  FROM `derived_circuit_voltages`
+  WHERE `circuit_id` = `circuits`.`id`
+)
+WHERE `id` IN (
+  SELECT `circuit_id`
+  FROM `derived_circuit_voltages`
+);

src/db/migrations/0022_default_remaining_phase_types.sql

@@ -0,0 +1,7 @@
+UPDATE `circuit_device_rows`
+SET `phase_type` = 'single_phase'
+WHERE `phase_type` IS NULL;
+--> statement-breakpoint
+UPDATE `global_devices`
+SET `phase_count` = 1
+WHERE `phase_count` IS NULL OR `phase_count` NOT IN (1, 3);

src/db/migrations/0023_cheerful_night_thrasher.sql

@@ -0,0 +1 @@
+ALTER TABLE `distribution_boards` ADD `simultaneity_factor` real DEFAULT 1 NOT NULL;

src/db/migrations/meta/_journal.json

@@ -113,6 +113,62 @@
       "when": 1785014383032,
       "tag": "0015_modern_madame_masque",
       "breakpoints": true
+    },
+    {
+      "idx": 16,
+      "version": "6",
+      "when": 1785254079435,
+      "tag": "0016_dashing_darkstar",
+      "breakpoints": true
+    },
+    {
+      "idx": 17,
+      "version": "6",
+      "when": 1785307189539,
+      "tag": "0017_vengeful_romulus",
+      "breakpoints": true
+    },
+    {
+      "idx": 18,
+      "version": "6",
+      "when": 1785308458789,
+      "tag": "0018_fancy_argent",
+      "breakpoints": true
+    },
+    {
+      "idx": 19,
+      "version": "6",
+      "when": 1785310907349,
+      "tag": "0019_normalize_project_voltages",
+      "breakpoints": true
+    },
+    {
+      "idx": 20,
+      "version": "6",
+      "when": 1785314248007,
+      "tag": "0020_normalize_phase_types",
+      "breakpoints": true
+    },
+    {
+      "idx": 21,
+      "version": "6",
+      "when": 1785314558555,
+      "tag": "0021_fill_missing_phase_types",
+      "breakpoints": true
+    },
+    {
+      "idx": 22,
+      "version": "6",
+      "when": 1785314626476,
+      "tag": "0022_default_remaining_phase_types",
+      "breakpoints": true
+    },
+    {
+      "idx": 23,
+      "version": "6",
+      "when": 1785343645615,
+      "tag": "0023_cheerful_night_thrasher",
+      "breakpoints": true
     }
   ]
 }

src/db/repositories/circuit-device-row-move-project-command.repository.ts

@@ -20,11 +20,14 @@ import { circuitLists } from "../schema/circuit-lists.js";
 import { circuitSections } from "../schema/circuit-sections.js";
 import { circuits } from "../schema/circuits.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { updateDerivedCircuitVoltage } from "./project-voltage.persistence.js";
+import { resolveCircuitVoltage } from "./project-voltage.persistence.js";
 
 interface PersistedMoveRow {
   id: string;
   circuitId: string;
   sortOrder: number;
+  phaseType: string | null;
 }
 
 export class CircuitDeviceRowMoveProjectCommandRepository
@@ -85,6 +88,7 @@ export class CircuitDeviceRowMoveProjectCommandRepository
       );
       this.applyMoves(database, command.payload.moves);
       this.updateReserveStates(database, circuitIds);
+      this.updateVoltages(database, projectId, circuitIds);
       return inverse;
     }
 
@@ -94,7 +98,16 @@ export class CircuitDeviceRowMoveProjectCommandRepository
     const { targetCircuit, targetCircuitAction, moves } =
       command.payload;
     const rowsById = this.loadExpectedRows(database, moves);
-    this.assertCircuitLocation(database, projectId, targetCircuit);
+    const appliedTargetCircuit = {
+      ...targetCircuit,
+      voltage: resolveCircuitVoltage(
+        database,
+        projectId,
+        targetCircuit.sectionId,
+        moves.map((move) => rowsById.get(move.rowId)?.phaseType)
+      ),
+    };
+    this.assertCircuitLocation(database, projectId, appliedTargetCircuit);
 
     if (targetCircuitAction === "create") {
       const sourceCircuitIds = [
@@ -106,13 +119,13 @@ export class CircuitDeviceRowMoveProjectCommandRepository
         sourceCircuitIds,
         targetCircuit.circuitListId
       );
-      this.assertTargetCircuitAvailable(database, targetCircuit);
+      this.assertTargetCircuitAvailable(database, appliedTargetCircuit);
-      this.insertTargetCircuit(database, targetCircuit);
+      this.insertTargetCircuit(database, appliedTargetCircuit);
 
       const inverse =
         createCircuitDeviceRowMoveWithNewCircuitProjectCommand(
           "delete",
-          targetCircuit,
+          appliedTargetCircuit,
           this.reverseMoves(moves, rowsById)
         );
       this.applyMoves(database, moves);
@@ -120,12 +133,16 @@ export class CircuitDeviceRowMoveProjectCommandRepository
         ...sourceCircuitIds,
         targetCircuit.id,
       ]);
+      this.updateVoltages(database, projectId, [
+        ...sourceCircuitIds,
+        targetCircuit.id,
+      ]);
       return inverse;
     }
 
     this.assertTargetCircuitUnchanged(
       database,
-      targetCircuit,
+      appliedTargetCircuit,
       moves.map((move) => move.rowId)
     );
     const destinationCircuitIds = [
@@ -140,7 +157,7 @@ export class CircuitDeviceRowMoveProjectCommandRepository
     const inverse =
       createCircuitDeviceRowMoveWithNewCircuitProjectCommand(
         "create",
-        targetCircuit,
+        appliedTargetCircuit,
         this.reverseMoves(moves, rowsById)
       );
     this.applyMoves(database, moves);
@@ -148,6 +165,11 @@ export class CircuitDeviceRowMoveProjectCommandRepository
       targetCircuit.id,
       ...destinationCircuitIds,
     ]);
+    this.updateVoltages(
+      database,
+      projectId,
+      destinationCircuitIds
+    );
     const deleted = database
       .delete(circuits)
       .where(
@@ -169,6 +191,16 @@ export class CircuitDeviceRowMoveProjectCommandRepository
     return inverse;
   }
 
+  private updateVoltages(
+    database: AppDatabase,
+    projectId: string,
+    circuitIds: string[]
+  ) {
+    for (const circuitId of new Set(circuitIds)) {
+      updateDerivedCircuitVoltage(database, projectId, circuitId);
+    }
+  }
+
   private loadExpectedRows(
     database: AppDatabase,
     moves: CircuitDeviceRowMoveAssignment[]
@@ -179,6 +211,7 @@ export class CircuitDeviceRowMoveProjectCommandRepository
         id: circuitDeviceRows.id,
         circuitId: circuitDeviceRows.circuitId,
         sortOrder: circuitDeviceRows.sortOrder,
+        phaseType: circuitDeviceRows.phaseType,
       })
       .from(circuitDeviceRows)
       .where(inArray(circuitDeviceRows.id, rowIds))

src/db/repositories/circuit-device-row-project-command.repository.ts

@@ -11,6 +11,7 @@ import type {
   ExecuteCircuitDeviceRowUpdateCommandInput,
 } from "../../domain/ports/circuit-device-row-project-command.store.js";
 import { deriveOverriddenFieldsForLocalEdit } from "../../domain/services/project-device-overrides.js";
+import { isElectricalPhaseType } from "../../domain/services/project-voltage.service.js";
 import type { AppDatabase } from "../database-context.js";
 import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
 import { circuitLists } from "../schema/circuit-lists.js";
@@ -22,6 +23,7 @@ import {
   type CircuitDeviceRowPatchInput,
 } from "./circuit-device-row.persistence.js";
 import { executeProjectCommandTransactionWithAppliedForward } from "./project-command-transaction.persistence.js";
+import { updateDerivedCircuitVoltage } from "./project-voltage.persistence.js";
 
 type CircuitDeviceRow = typeof circuitDeviceRows.$inferSelect;
 
@@ -80,6 +82,13 @@ export class CircuitDeviceRowProjectCommandRepository
         change.value,
       ])
     ) as CircuitDeviceRowPatchInput;
+    if (
+      input.source === "user" &&
+      patch.phaseType !== undefined &&
+      !isElectricalPhaseType(patch.phaseType)
+    ) {
+      throw new Error("Device-row phase type is invalid.");
+    }
     this.assertLinkedProjectDevice(tx, input.projectId, patch);
     this.assertRoom(tx, input.projectId, patch);
 
@@ -117,6 +126,13 @@ export class CircuitDeviceRowProjectCommandRepository
     if (update.changes !== 1) {
       throw new Error("Circuit device row changed before command execution.");
     }
+    if (patch.phaseType !== undefined) {
+      updateDerivedCircuitVoltage(
+        tx,
+        input.projectId,
+        current.circuitId
+      );
+    }
 
     return {
       forward: appliedForward,

src/db/repositories/circuit-device-row-structure-project-command.repository.ts

@@ -14,6 +14,7 @@ import type {
   ExecuteCircuitDeviceRowStructureCommandInput,
 } from "../../domain/ports/circuit-device-row-structure-project-command.store.js";
 import type { AppDatabase } from "../database-context.js";
+import { isElectricalPhaseType } from "../../domain/services/project-voltage.service.js";
 import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
 import { circuitLists } from "../schema/circuit-lists.js";
 import { circuits } from "../schema/circuits.js";
@@ -22,6 +23,7 @@ import {
   toCircuitDeviceRowSnapshot,
 } from "./circuit-device-row-structure.persistence.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { updateDerivedCircuitVoltage } from "./project-voltage.persistence.js";
 
 export class CircuitDeviceRowStructureProjectCommandRepository
   implements CircuitDeviceRowStructureProjectCommandStore
@@ -80,6 +82,9 @@ export class CircuitDeviceRowStructureProjectCommandRepository
         "User commands cannot assign legacy consumer ids."
       );
     }
+    if (source === "user" && !isElectricalPhaseType(row.phaseType)) {
+      throw new Error("Device-row phase type is invalid.");
+    }
     this.assertCircuitInProject(database, projectId, row.circuitId);
     assertCircuitDeviceRowReferencesInProject(database, projectId, row);
 
@@ -101,6 +106,7 @@ export class CircuitDeviceRowStructureProjectCommandRepository
     if (circuitUpdate.changes !== 1) {
       throw new Error("Circuit changed before device-row insertion.");
     }
+    updateDerivedCircuitVoltage(database, projectId, row.circuitId);
 
     return createCircuitDeviceRowDeleteProjectCommand(
       row.id,
@@ -153,6 +159,11 @@ export class CircuitDeviceRowStructureProjectCommandRepository
     if (circuitUpdate.changes !== 1) {
       throw new Error("Circuit changed before device-row deletion.");
     }
+    updateDerivedCircuitVoltage(
+      database,
+      projectId,
+      expectedCircuitId
+    );
 
     return createCircuitDeviceRowInsertProjectCommand(
       toCircuitDeviceRowSnapshot(row)

src/db/repositories/circuit-project-command.repository.ts

@@ -18,7 +18,9 @@ import {
   toCircuitPatchValues,
   type CircuitPatchPersistenceInput,
 } from "./circuit.persistence.js";
-import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { executeProjectCommandTransactionWithAppliedForward } from "./project-command-transaction.persistence.js";
+import { resolveCircuitVoltage } from "./project-voltage.persistence.js";
+import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
 
 type CircuitRow = typeof circuits.$inferSelect;
 
@@ -30,7 +32,7 @@ export class CircuitProjectCommandRepository
   executeUpdate(input: ExecuteCircuitUpdateCommandInput) {
     assertCircuitUpdateProjectCommand(input.command);
 
-    return executeProjectCommandTransaction(
+    return executeProjectCommandTransactionWithAppliedForward(
       this.database,
       input,
       (tx) => this.applyCommand(tx, input)
@@ -71,14 +73,44 @@ export class CircuitProjectCommandRepository
       ])
     ) as CircuitPatchPersistenceInput;
     this.assertSectionInCircuitList(tx, current, patch.sectionId);
+    if (input.source === "user") {
+      if (
+        input.command.payload.changes.every(
+          (change) => change.field === "voltage"
+        )
+      ) {
+        throw new Error("Circuit voltage is derived and cannot be edited.");
+      }
+      const devicePhaseTypes = tx
+        .select({ phaseType: circuitDeviceRows.phaseType })
+        .from(circuitDeviceRows)
+        .where(eq(circuitDeviceRows.circuitId, current.id))
+        .all()
+        .map((row) => row.phaseType);
+      const derivedVoltage = resolveCircuitVoltage(
+        tx,
+        input.projectId,
+        patch.sectionId ?? current.sectionId,
+        devicePhaseTypes
+      );
+      if (derivedVoltage === current.voltage) {
+        delete patch.voltage;
+      } else {
+        patch.voltage = derivedVoltage;
+      }
+    }
     this.assertUniqueEquipmentIdentifier(
       tx,
       current,
       patch.equipmentIdentifier
     );
 
+    const appliedForward = createCircuitUpdateProjectCommand(
+      current.id,
+      patch as CircuitUpdatePatch
+    );
     const inversePatch = Object.fromEntries(
-      input.command.payload.changes.map((change) => [
+      appliedForward.payload.changes.map((change) => [
         change.field,
         getCircuitFieldValue(current, change.field),
       ])
@@ -97,7 +129,7 @@ export class CircuitProjectCommandRepository
       throw new Error("Circuit changed before command execution.");
     }
 
-    return inverse;
+    return { forward: appliedForward, inverse };
   }
 
   private assertSectionInCircuitList(

src/db/repositories/circuit-structure-project-command.repository.ts

@@ -13,6 +13,7 @@ import type {
   CircuitStructureProjectCommandStore,
   ExecuteCircuitStructureCommandInput,
 } from "../../domain/ports/circuit-structure-project-command.store.js";
+import { isElectricalPhaseType } from "../../domain/services/project-voltage.service.js";
 import type { AppDatabase } from "../database-context.js";
 import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
 import { circuitLists } from "../schema/circuit-lists.js";
@@ -23,6 +24,7 @@ import {
   toCircuitDeviceRowSnapshot,
 } from "./circuit-device-row-structure.persistence.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { resolveCircuitVoltage } from "./project-voltage.persistence.js";
 
 export class CircuitStructureProjectCommandRepository
   implements CircuitStructureProjectCommandStore
@@ -77,6 +79,19 @@ export class CircuitStructureProjectCommandRepository
     snapshot: CircuitSnapshot
   ) {
     this.assertCircuitLocation(database, projectId, snapshot);
+    if (source === "user") {
+      const derivedVoltage = resolveCircuitVoltage(
+        database,
+        projectId,
+        snapshot.sectionId,
+        snapshot.deviceRows.map((row) => row.phaseType)
+      );
+      if (snapshot.voltage !== derivedVoltage) {
+        throw new Error(
+          "Circuit voltage must match the project phase voltage."
+        );
+      }
+    }
 
     const existingCircuit = database
       .select({ id: circuits.id })
@@ -122,6 +137,9 @@ export class CircuitStructureProjectCommandRepository
             "User commands cannot assign legacy consumer ids."
           );
         }
+        if (source === "user" && !isElectricalPhaseType(row.phaseType)) {
+          throw new Error("Device-row phase type is invalid.");
+        }
         assertCircuitDeviceRowReferencesInProject(
           database,
           projectId,

src/db/repositories/distribution-board-structure-project-command.repository.ts

@@ -6,9 +6,20 @@ import {
   createDistributionBoardInsertProjectCommand,
   distributionBoardDeleteCommandType,
   distributionBoardInsertCommandType,
+  normalizeDistributionBoardStructureProjectCommand,
   type DistributionBoardStructureProjectCommand,
   type DistributionBoardStructureSnapshot,
+  legacyDistributionBoardStructureCommandSchemaVersion,
 } from "../../domain/models/distribution-board-structure-project-command.model.js";
+import {
+  assertDistributionBoardUpdateProjectCommand,
+  createDistributionBoardUpdateProjectCommand,
+  legacyDistributionBoardUpdateCommandSchemaVersion,
+  type DistributionBoardUpdateField,
+  type DistributionBoardUpdatePatch,
+  type DistributionBoardUpdateProjectCommand,
+  type DistributionBoardUpdateValues,
+} from "../../domain/models/distribution-board-project-command.model.js";
 import type {
   DistributionBoardStructureProjectCommandStore,
   ExecuteDistributionBoardStructureCommandInput,
@@ -18,6 +29,7 @@ import { circuitLists } from "../schema/circuit-lists.js";
 import { circuitSections } from "../schema/circuit-sections.js";
 import { circuits } from "../schema/circuits.js";
 import { distributionBoards } from "../schema/distribution-boards.js";
+import { floors } from "../schema/floors.js";
 import { projects } from "../schema/projects.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
 
@@ -35,26 +47,52 @@ export class DistributionBoardStructureProjectCommandRepository
     );
   }
 
+  executeUpdate(
+    input: Omit<
+      ExecuteDistributionBoardStructureCommandInput,
+      "command"
+    > & {
+      command: DistributionBoardUpdateProjectCommand;
+    }
+  ) {
+    assertDistributionBoardUpdateProjectCommand(input.command);
+    return executeProjectCommandTransaction(
+      this.database,
+      input,
+      (tx) => this.update(tx, input)
+    );
+  }
+
   private applyCommand(
     database: AppDatabase,
     projectId: string,
     command: DistributionBoardStructureProjectCommand
   ): DistributionBoardStructureProjectCommand {
-    if (command.type === distributionBoardInsertCommandType) {
+    const normalized =
-      assertDistributionBoardInsertProjectCommand(command);
+      normalizeDistributionBoardStructureProjectCommand(command);
-      return this.insert(
+    if (normalized.type === distributionBoardInsertCommandType) {
+      assertDistributionBoardInsertProjectCommand(normalized);
+      const inverse = this.insert(
         database,
         projectId,
-        command.payload.structure
+        normalized.payload.structure
       );
+      return command.schemaVersion ===
+        legacyDistributionBoardStructureCommandSchemaVersion
+        ? toLegacyStructureCommand(inverse)
+        : inverse;
     }
-    if (command.type === distributionBoardDeleteCommandType) {
+    if (normalized.type === distributionBoardDeleteCommandType) {
-      assertDistributionBoardDeleteProjectCommand(command);
+      assertDistributionBoardDeleteProjectCommand(normalized);
-      return this.delete(
+      const inverse = this.delete(
         database,
         projectId,
-        command.payload.structure
+        normalized.payload.structure
       );
+      return command.schemaVersion ===
+        legacyDistributionBoardStructureCommandSchemaVersion
+        ? toLegacyStructureCommand(inverse)
+        : inverse;
     }
     throw new Error("Unsupported distribution-board structure command.");
   }
@@ -73,13 +111,33 @@ export class DistributionBoardStructureProjectCommandRepository
       );
     }
     const project = database
-      .select({ id: projects.id })
+      .select({
+        id: projects.id,
+        enabledSupplyTypes:
+          projects.enabledDistributionBoardSupplyTypes,
+      })
       .from(projects)
       .where(eq(projects.id, projectId))
       .get();
     if (!project) {
       throw new Error("Project not found.");
     }
+    assertSupplyTypeEnabled(
+      project.enabledSupplyTypes,
+      structure.distributionBoard.supplyType
+    );
+    if (structure.distributionBoard.floorId !== null) {
+      const floor = database
+        .select({ projectId: floors.projectId })
+        .from(floors)
+        .where(eq(floors.id, structure.distributionBoard.floorId))
+        .get();
+      if (!floor || floor.projectId !== projectId) {
+        throw new Error(
+          "Distribution-board floor does not belong to project."
+        );
+      }
+    }
     const existingBoard = database
       .select({ id: distributionBoards.id })
       .from(distributionBoards)
@@ -179,6 +237,148 @@ export class DistributionBoardStructureProjectCommandRepository
     }
     return createDistributionBoardInsertProjectCommand(structure);
   }
+
+  private update(
+    database: AppDatabase,
+    input: Omit<
+      ExecuteDistributionBoardStructureCommandInput,
+      "command"
+    > & {
+      command: DistributionBoardUpdateProjectCommand;
+    }
+  ) {
+    const current = database
+      .select()
+      .from(distributionBoards)
+      .where(
+        and(
+          eq(
+            distributionBoards.id,
+            input.command.payload.distributionBoardId
+          ),
+          eq(distributionBoards.projectId, input.projectId)
+        )
+      )
+      .get();
+    if (!current) {
+      throw new Error("Distribution board does not belong to project.");
+    }
+    const project = database
+      .select({
+        enabledSupplyTypes:
+          projects.enabledDistributionBoardSupplyTypes,
+      })
+      .from(projects)
+      .where(eq(projects.id, input.projectId))
+      .get();
+    if (!project) {
+      throw new Error("Project not found.");
+    }
+    const patch = Object.fromEntries(
+      input.command.payload.changes.map((change) => [
+        change.field,
+        change.value,
+      ])
+    ) as DistributionBoardUpdatePatch;
+    if (patch.floorId !== undefined && patch.floorId !== null) {
+      const floor = database
+        .select({ projectId: floors.projectId })
+        .from(floors)
+        .where(eq(floors.id, patch.floorId))
+        .get();
+      if (!floor || floor.projectId !== input.projectId) {
+        throw new Error(
+          "Distribution-board floor does not belong to project."
+        );
+      }
+    }
+    if (patch.supplyType !== undefined) {
+      assertSupplyTypeEnabled(
+        project.enabledSupplyTypes,
+        patch.supplyType
+      );
+    }
+    const inversePatch = Object.fromEntries(
+      input.command.payload.changes.map((change) => [
+        change.field,
+        getDistributionBoardFieldValue(current, change.field),
+      ])
+    ) as DistributionBoardUpdatePatch;
+    const currentInverse = createDistributionBoardUpdateProjectCommand(
+      current.id,
+      inversePatch
+    );
+    const inverse =
+      input.command.schemaVersion ===
+      legacyDistributionBoardUpdateCommandSchemaVersion
+        ? ({
+            ...currentInverse,
+            schemaVersion:
+              legacyDistributionBoardUpdateCommandSchemaVersion,
+          } as DistributionBoardUpdateProjectCommand)
+        : currentInverse;
+    const updated = database
+      .update(distributionBoards)
+      .set(patch)
+      .where(
+        and(
+          eq(distributionBoards.id, current.id),
+          eq(distributionBoards.projectId, input.projectId)
+        )
+      )
+      .run();
+    if (updated.changes !== 1) {
+      throw new Error(
+        "Distribution board changed before command execution."
+      );
+    }
+    return inverse;
+  }
+}
+
+function assertSupplyTypeEnabled(
+  enabledSupplyTypes: (typeof projects.$inferSelect)["enabledDistributionBoardSupplyTypes"],
+  supplyType: (typeof distributionBoards.$inferSelect)["supplyType"]
+) {
+  if (
+    supplyType !== null &&
+    !enabledSupplyTypes.includes(supplyType)
+  ) {
+    throw new Error(
+      `Die Netzart ${supplyType} ist in den Projekteinstellungen nicht aktiviert.`
+    );
+  }
+}
+
+function toLegacyStructureCommand(
+  command:
+    | ReturnType<typeof createDistributionBoardInsertProjectCommand>
+    | ReturnType<typeof createDistributionBoardDeleteProjectCommand>
+): DistributionBoardStructureProjectCommand {
+  const {
+    floorId: _floorId,
+    supplyType: _supplyType,
+    ...distributionBoard
+  } = command.payload.structure.distributionBoard;
+  return {
+    schemaVersion: legacyDistributionBoardStructureCommandSchemaVersion,
+    type: command.type,
+    payload: {
+      structure: {
+        ...command.payload.structure,
+        distributionBoard,
+      },
+    },
+  } as DistributionBoardStructureProjectCommand;
+}
+
+function getDistributionBoardFieldValue<
+  TField extends DistributionBoardUpdateField,
+>(
+  distributionBoard: typeof distributionBoards.$inferSelect,
+  field: TField
+): DistributionBoardUpdateValues[TField] {
+  return distributionBoard[field] as DistributionBoardUpdateValues[TField];
 }
 
 function structureMatches(
@@ -189,8 +389,16 @@ function structureMatches(
     sections: Array<typeof circuitSections.$inferSelect>;
   }
 ) {
+  const {
+    simultaneityFactor,
+    ...actualDistributionBoard
+  } = actual.board;
   if (
-    !sameRecord(expected.distributionBoard, actual.board) ||
+    simultaneityFactor !== 1 ||
+    !sameRecord(
+      expected.distributionBoard,
+      actualDistributionBoard
+    ) ||
     !sameRecord(expected.circuitList, actual.list) ||
     expected.sections.length !== actual.sections.length
   ) {

src/db/repositories/distribution-board.repository.ts

@@ -1,4 +1,4 @@
-import { eq } from "drizzle-orm";
+import { and, eq } from "drizzle-orm";
 import type { AppDatabase } from "../database-context.js";
 import { distributionBoards } from "../schema/distribution-boards.js";
 
@@ -12,4 +12,19 @@ export class DistributionBoardRepository {
       .where(eq(distributionBoards.projectId, projectId));
   }
 
+  async findById(projectId: string, distributionBoardId: string) {
+    return (
+      this.database
+        .select()
+        .from(distributionBoards)
+        .where(
+          and(
+            eq(distributionBoards.projectId, projectId),
+            eq(distributionBoards.id, distributionBoardId)
+          )
+        )
+        .get() ?? null
+    );
+  }
+
 }

src/db/repositories/global-device.repository.ts

@@ -26,8 +26,8 @@ export class GlobalDeviceRepository {
       quantity: input.quantity,
       installedPowerPerUnitKw: input.installedPowerPerUnitKw,
       demandFactor: input.demandFactor,
-      voltageV: input.voltageV ?? null,
+      voltageV: null,
-      phaseCount: input.phaseCount ?? null,
+      phaseCount: input.phaseCount,
       powerFactor: input.powerFactor ?? null,
       note: input.note ?? null,
     });
@@ -45,8 +45,8 @@ export class GlobalDeviceRepository {
         quantity: input.quantity,
         installedPowerPerUnitKw: input.installedPowerPerUnitKw,
         demandFactor: input.demandFactor,
-        voltageV: input.voltageV ?? null,
+        voltageV: null,
-        phaseCount: input.phaseCount ?? null,
+        phaseCount: input.phaseCount,
         powerFactor: input.powerFactor ?? null,
         note: input.note ?? null,
       })

src/db/repositories/project-device-project-command.repository.ts

@@ -12,7 +12,8 @@ import type {
 } from "../../domain/ports/project-device-project-command.store.js";
 import type { AppDatabase } from "../database-context.js";
 import { projectDevices } from "../schema/project-devices.js";
-import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { executeProjectCommandTransactionWithAppliedForward } from "./project-command-transaction.persistence.js";
+import { resolveProjectDeviceVoltage } from "./project-voltage.persistence.js";
 
 type ProjectDeviceRow = typeof projectDevices.$inferSelect;
 
@@ -24,7 +25,7 @@ export class ProjectDeviceProjectCommandRepository
   executeUpdate(input: ExecuteProjectDeviceUpdateCommandInput) {
     assertProjectDeviceUpdateProjectCommand(input.command);
 
-    return executeProjectCommandTransaction(
+    return executeProjectCommandTransactionWithAppliedForward(
       this.database,
       input,
       (tx) => this.applyCommand(tx, input)
@@ -60,8 +61,40 @@ export class ProjectDeviceProjectCommandRepository
         change.value,
       ])
     ) as ProjectDeviceUpdatePatch;
+    if (input.source === "user") {
+      if (
+        input.command.payload.changes.every(
+          (change) => change.field === "voltageV"
+        )
+      ) {
+        throw new Error(
+          "Project-device voltage is derived and cannot be edited."
+        );
+      }
+      const targetPhaseType = patch.phaseType ?? current.phaseType;
+      if (
+        targetPhaseType !== "single_phase" &&
+        targetPhaseType !== "three_phase"
+      ) {
+        throw new Error("Project-device phase type is invalid.");
+      }
+      const derivedVoltage = resolveProjectDeviceVoltage(
+        tx,
+        input.projectId,
+        targetPhaseType
+      );
+      if (derivedVoltage === current.voltageV) {
+        delete patch.voltageV;
+      } else {
+        patch.voltageV = derivedVoltage;
+      }
+    }
+    const appliedForward = createProjectDeviceUpdateProjectCommand(
+      current.id,
+      patch
+    );
     const inversePatch = Object.fromEntries(
-      input.command.payload.changes.map((change) => [
+      appliedForward.payload.changes.map((change) => [
         change.field,
         getProjectDeviceFieldValue(current, change.field),
       ])
@@ -87,7 +120,7 @@ export class ProjectDeviceProjectCommandRepository
       );
     }
 
-    return inverse;
+    return { forward: appliedForward, inverse };
   }
 }
 

src/db/repositories/project-device-row-sync-project-command.repository.ts

@@ -16,6 +16,7 @@ import { circuitLists } from "../schema/circuit-lists.js";
 import { circuits } from "../schema/circuits.js";
 import { projectDevices } from "../schema/project-devices.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { updateDerivedCircuitVoltage } from "./project-voltage.persistence.js";
 
 type CircuitDeviceRow = typeof circuitDeviceRows.$inferSelect;
 
@@ -129,6 +130,25 @@ export class ProjectDeviceRowSyncProjectCommandRepository
         );
       }
     }
+    const affectedCircuitIds = new Set(
+      input.command.payload.rows
+        .filter(
+          (assignment) =>
+            assignment.expected.phaseType !==
+            assignment.target.phaseType
+        )
+        .map(
+          (assignment) =>
+            persistedById.get(assignment.rowId)!.circuitId
+        )
+    );
+    for (const circuitId of affectedCircuitIds) {
+      updateDerivedCircuitVoltage(
+        tx,
+        input.projectId,
+        circuitId
+      );
+    }
 
     return inverse;
   }

src/db/repositories/project-device-structure-project-command.repository.ts

@@ -28,6 +28,7 @@ import { projectDevices } from "../schema/project-devices.js";
 import { projects } from "../schema/projects.js";
 import { toCircuitDeviceRowSnapshot } from "./circuit-device-row-structure.persistence.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { resolveProjectDeviceVoltage } from "./project-voltage.persistence.js";
 
 const circuitDeviceRowSnapshotFields = [
   "id",
@@ -125,6 +126,19 @@ export class ProjectDeviceStructureProjectCommandRepository
     if (!project) {
       throw new Error("Project does not exist.");
     }
+    if (
+      source === "user" &&
+      snapshot.voltageV !==
+        resolveProjectDeviceVoltage(
+          database,
+          projectId,
+          snapshot.phaseType
+        )
+    ) {
+      throw new Error(
+        "Project-device voltage must match the project phase voltage."
+      );
+    }
     const existing = database
       .select({ id: projectDevices.id })
       .from(projectDevices)

src/db/repositories/project-history.repository.ts

@@ -1,10 +1,11 @@
-import { and, asc, desc, eq, lt } from "drizzle-orm";
+import { and, asc, desc, eq, inArray, lt } from "drizzle-orm";
 import { deserializeProjectCommand } from "../../domain/models/project-command.model.js";
 import type {
   ProjectHistoryCommand,
   ProjectHistoryDirection,
   ListProjectRevisionsInput,
   ProjectRevisionPage,
+  ProjectRevisionSummary,
   ProjectHistoryState,
   ProjectHistoryStore,
 } from "../../domain/ports/project-history.store.js";
@@ -118,6 +119,64 @@ export class ProjectHistoryRepository implements ProjectHistoryStore {
     };
   }
 
+  listRevisionsByNumbers(
+    projectId: string,
+    revisionNumbers: number[]
+  ): ProjectRevisionSummary[] {
+    for (const revisionNumber of revisionNumbers) {
+      if (
+        !Number.isSafeInteger(revisionNumber) ||
+        revisionNumber < 0
+      ) {
+        throw new Error(
+          "Project revision numbers must be non-negative integers."
+        );
+      }
+    }
+    const normalizedRevisionNumbers = [
+      ...new Set(revisionNumbers),
+    ].filter((revisionNumber) => revisionNumber > 0);
+    if (!normalizedRevisionNumbers.length) {
+      return [];
+    }
+
+    return this.database
+      .select({
+        revisionId: projectRevisions.id,
+        changeSetId: projectChangeSets.id,
+        revisionNumber: projectRevisions.revisionNumber,
+        createdAtIso: projectRevisions.createdAtIso,
+        actorId: projectRevisions.actorId,
+        source: projectRevisions.source,
+        description: projectRevisions.description,
+        commandType: projectChangeSets.commandType,
+        payloadSchemaVersion: projectChangeSets.payloadSchemaVersion,
+      })
+      .from(projectRevisions)
+      .innerJoin(
+        projectChangeSets,
+        eq(
+          projectChangeSets.projectRevisionId,
+          projectRevisions.id
+        )
+      )
+      .where(
+        and(
+          eq(projectRevisions.projectId, projectId),
+          inArray(
+            projectRevisions.revisionNumber,
+            normalizedRevisionNumbers
+          )
+        )
+      )
+      .orderBy(desc(projectRevisions.revisionNumber))
+      .all()
+      .map((row) => ({
+        ...row,
+        source: row.source as ProjectRevisionSource,
+      }));
+  }
+
   getNextCommand(
     projectId: string,
     direction: ProjectHistoryDirection

src/db/repositories/project-location-structure-project-command.repository.ts

@@ -24,6 +24,7 @@ import type { AppDatabase } from "../database-context.js";
 import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
 import { consumers } from "../schema/consumers.js";
 import { floors } from "../schema/floors.js";
+import { distributionBoards } from "../schema/distribution-boards.js";
 import { projects } from "../schema/projects.js";
 import { rooms } from "../schema/rooms.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
@@ -129,6 +130,17 @@ export class ProjectLocationStructureProjectCommandRepository
         "A project floor with assigned rooms cannot be removed by history."
       );
     }
+    const referencedDistributionBoard = database
+      .select({ id: distributionBoards.id })
+      .from(distributionBoards)
+      .where(eq(distributionBoards.floorId, expected.id))
+      .limit(1)
+      .get();
+    if (referencedDistributionBoard) {
+      throw new Error(
+        "A project floor assigned to a distribution board cannot be removed by history."
+      );
+    }
     const deleted = database
       .delete(floors)
       .where(

src/db/repositories/project-settings-project-command.repository.ts

@@ -1,7 +1,11 @@
-import { eq } from "drizzle-orm";
+import { and, eq, isNotNull } from "drizzle-orm";
 import {
   assertProjectSettingsUpdateProjectCommand,
   createProjectSettingsUpdateProjectCommand,
+  legacyProjectSettingsUpdateCommandSchemaVersion,
+  normalizeProjectSettingsValues,
+  previousProjectSettingsUpdateCommandSchemaVersion,
+  type ProjectSettingsValues,
 } from "../../domain/models/project-settings-project-command.model.js";
 import type {
   ExecuteProjectSettingsUpdateCommandInput,
@@ -9,7 +13,9 @@ import type {
 } from "../../domain/ports/project-settings-project-command.store.js";
 import type { AppDatabase } from "../database-context.js";
 import { projects } from "../schema/projects.js";
+import { distributionBoards } from "../schema/distribution-boards.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { updateAllDerivedProjectVoltages } from "./project-voltage.persistence.js";
 
 export class ProjectSettingsProjectCommandRepository
   implements ProjectSettingsProjectCommandStore
@@ -37,28 +43,124 @@ export class ProjectSettingsProjectCommandRepository
     if (!current) {
       throw new Error("Project not found.");
     }
-    if (
+    const target = normalizeProjectSettingsValues(input.command, current);
-      current.singlePhaseVoltageV ===
+    if (projectSettingsEqual(current, target)) {
-        input.command.payload.singlePhaseVoltageV &&
-      current.threePhaseVoltageV ===
-        input.command.payload.threePhaseVoltageV
-    ) {
       throw new Error("Project settings did not change.");
     }
 
-    const inverse = createProjectSettingsUpdateProjectCommand({
+    const inverse =
+      input.command.schemaVersion ===
+      legacyProjectSettingsUpdateCommandSchemaVersion
+        ? {
+            schemaVersion: legacyProjectSettingsUpdateCommandSchemaVersion,
+            type: input.command.type,
+            payload: {
               singlePhaseVoltageV: current.singlePhaseVoltageV,
               threePhaseVoltageV: current.threePhaseVoltageV,
+            },
+          }
+        : input.command.schemaVersion ===
+            previousProjectSettingsUpdateCommandSchemaVersion
+          ? {
+              schemaVersion:
+                previousProjectSettingsUpdateCommandSchemaVersion,
+              type: input.command.type,
+              payload: {
+                name: current.name,
+                internalProjectNumber: current.internalProjectNumber,
+                externalProjectNumber: current.externalProjectNumber,
+                buildingOwner: current.buildingOwner,
+                description: current.description,
+                singlePhaseVoltageV: current.singlePhaseVoltageV,
+                threePhaseVoltageV: current.threePhaseVoltageV,
+              },
+            }
+          : createProjectSettingsUpdateProjectCommand({
+            name: current.name,
+            internalProjectNumber: current.internalProjectNumber,
+            externalProjectNumber: current.externalProjectNumber,
+            buildingOwner: current.buildingOwner,
+            description: current.description,
+            singlePhaseVoltageV: current.singlePhaseVoltageV,
+            threePhaseVoltageV: current.threePhaseVoltageV,
+            enabledDistributionBoardSupplyTypes:
+              current.enabledDistributionBoardSupplyTypes,
           });
+    assertDisabledSupplyTypesAreUnused(tx, input.projectId, target);
     const updated = tx
       .update(projects)
-      .set(input.command.payload)
+      .set(target)
       .where(eq(projects.id, input.projectId))
       .run();
     if (updated.changes !== 1) {
       throw new Error("Project changed before settings update.");
     }
+    updateAllDerivedProjectVoltages(tx, input.projectId);
 
     return inverse;
   }
 }
+
+function projectSettingsEqual(
+  current: ProjectSettingsValues,
+  target: ProjectSettingsValues
+) {
+  return (
+    current.name === target.name &&
+    current.internalProjectNumber === target.internalProjectNumber &&
+    current.externalProjectNumber === target.externalProjectNumber &&
+    current.buildingOwner === target.buildingOwner &&
+    current.description === target.description &&
+    current.singlePhaseVoltageV === target.singlePhaseVoltageV &&
+    current.threePhaseVoltageV === target.threePhaseVoltageV
+    && sameSupplyTypes(
+      current.enabledDistributionBoardSupplyTypes,
+      target.enabledDistributionBoardSupplyTypes
+    )
+  );
+}
+
+function sameSupplyTypes(
+  left: ProjectSettingsValues["enabledDistributionBoardSupplyTypes"],
+  right: ProjectSettingsValues["enabledDistributionBoardSupplyTypes"]
+) {
+  return (
+    left.length === right.length &&
+    left.every((value, index) => value === right[index])
+  );
+}
+
+function assertDisabledSupplyTypesAreUnused(
+  database: AppDatabase,
+  projectId: string,
+  target: ProjectSettingsValues
+) {
+  const used = database
+    .select({ supplyType: distributionBoards.supplyType })
+    .from(distributionBoards)
+    .where(
+      and(
+        eq(distributionBoards.projectId, projectId),
+        isNotNull(distributionBoards.supplyType)
+      )
+    )
+    .all();
+  const disabledUsedTypes = [
+    ...new Set(
+      used
+        .map((entry) => entry.supplyType)
+        .filter(
+          (supplyType) =>
+            supplyType !== null &&
+            !target.enabledDistributionBoardSupplyTypes.some(
+              (enabled) => enabled === supplyType
+            )
+        )
+    ),
+  ];
+  if (disabledUsedTypes.length > 0) {
+    throw new Error(
+      `Verwendete Netzarten können nicht deaktiviert werden: ${disabledUsedTypes.join(", ")}.`
+    );
+  }
+}

src/db/repositories/project-snapshot.repository.ts

@@ -4,8 +4,13 @@ import { ProjectRevisionConflictError } from "../../domain/errors/project-revisi
 import { ProjectSnapshotNameConflictError } from "../../domain/errors/project-snapshot-name-conflict.error.js";
 import { createProjectStateRestoreCommand } from "../../domain/models/project-state-restore-command.model.js";
 import {
+  distributionBoardProjectStateSnapshotSchemaVersion,
   deserializeProjectStateSnapshot,
+  legacyProjectStateSnapshotSchemaVersion,
+  previousProjectStateSnapshotSchemaVersion,
   projectStateSnapshotSchemaVersion,
+  supplyTypesProjectStateSnapshotSchemaVersion,
+  voltageProjectStateSnapshotSchemaVersion,
 } from "../../domain/models/project-state-snapshot.model.js";
 import type {
   CreateNamedProjectSnapshotInput,
@@ -138,7 +143,17 @@ export class ProjectSnapshotRepository implements ProjectSnapshotStore {
     if (actualChecksum !== stored.payloadSha256) {
       throw new Error("Project snapshot checksum verification failed.");
     }
-    if (stored.schemaVersion !== projectStateSnapshotSchemaVersion) {
+    if (
+      stored.schemaVersion !== legacyProjectStateSnapshotSchemaVersion &&
+      stored.schemaVersion !== previousProjectStateSnapshotSchemaVersion &&
+      stored.schemaVersion !==
+        distributionBoardProjectStateSnapshotSchemaVersion &&
+      stored.schemaVersion !==
+        supplyTypesProjectStateSnapshotSchemaVersion &&
+      stored.schemaVersion !==
+        voltageProjectStateSnapshotSchemaVersion &&
+      stored.schemaVersion !== projectStateSnapshotSchemaVersion
+    ) {
       throw new Error("Project snapshot schema version is not supported.");
     }
     const targetState = deserializeProjectStateSnapshot(stored.payloadJson);

src/db/repositories/project-state-restore-command.repository.ts

@@ -5,7 +5,7 @@ import {
   createProjectStateRestoreCommand,
 } from "../../domain/models/project-state-restore-command.model.js";
 import {
-  serializeProjectStateSnapshot,
+  parseProjectStateSnapshot,
   type ProjectStateSnapshot,
 } from "../../domain/models/project-state-snapshot.model.js";
 import type {
@@ -23,11 +23,11 @@ import { floors } from "../schema/floors.js";
 import { legacyConsumerCircuitMigrations } from "../schema/legacy-consumer-circuit-migrations.js";
 import { legacyConsumerMigrationReports } from "../schema/legacy-consumer-migration-report.js";
 import { projectDevices } from "../schema/project-devices.js";
+import { projectChangeSets } from "../schema/project-change-sets.js";
 import { projects } from "../schema/projects.js";
 import { rooms } from "../schema/rooms.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
 import {
-  hashProjectStatePayload,
   readProjectStateSnapshot,
 } from "./project-state-snapshot.persistence.js";
 
@@ -38,7 +38,10 @@ export class ProjectStateRestoreCommandRepository
 
   execute(input: ExecuteProjectStateRestoreCommandInput) {
     assertProjectStateRestoreCommand(input.command);
-    if (input.command.payload.targetState.project.id !== input.projectId) {
+    const targetState = parseProjectStateSnapshot(
+      input.command.payload.targetState
+    );
+    if (targetState.project.id !== input.projectId) {
       throw new Error("Restore state belongs to a different project.");
     }
 
@@ -59,7 +62,8 @@ export class ProjectStateRestoreCommandRepository
     }
     if (
       current.payloadSha256 !==
-      input.command.payload.expectedStateSha256
+        input.command.payload.expectedStateSha256 &&
+      !matchesHistoryRestoreTarget(tx, input, current.state)
     ) {
       throw new ProjectStateConflictError(
         input.projectId,
@@ -68,20 +72,93 @@ export class ProjectStateRestoreCommandRepository
       );
     }
 
-    const targetPayloadJson = serializeProjectStateSnapshot(
+    const targetState = parseProjectStateSnapshot(
       input.command.payload.targetState
     );
+    replaceProjectState(tx, targetState);
+    const persistedTarget = readProjectStateSnapshot(tx, input.projectId);
+    if (!persistedTarget) {
+      throw new Error("Restored project could not be loaded.");
+    }
     const inverse = createProjectStateRestoreCommand(
-      hashProjectStatePayload(targetPayloadJson),
+      persistedTarget.payloadSha256,
       current.state
     );
 
-    replaceProjectState(tx, input.command.payload.targetState);
-
     return inverse;
   }
 }
 
+function matchesHistoryRestoreTarget(
+  database: AppDatabase,
+  input: ExecuteProjectStateRestoreCommandInput,
+  currentState: ProjectStateSnapshot
+) {
+  if (
+    (input.source !== "undo" && input.source !== "redo") ||
+    !input.historyTargetChangeSetId
+  ) {
+    return false;
+  }
+  const changeSet = database
+    .select({
+      forwardPayloadJson: projectChangeSets.forwardPayloadJson,
+      inversePayloadJson: projectChangeSets.inversePayloadJson,
+    })
+    .from(projectChangeSets)
+    .where(eq(projectChangeSets.id, input.historyTargetChangeSetId))
+    .get();
+  if (!changeSet) {
+    return false;
+  }
+  try {
+    const serialized =
+      input.source === "undo"
+        ? changeSet.forwardPayloadJson
+        : changeSet.inversePayloadJson;
+    const command = JSON.parse(serialized) as {
+      type?: unknown;
+      payload?: { targetState?: unknown };
+    };
+    if (command.type !== "project.restore-state") {
+      return false;
+    }
+    const expectedState = parseProjectStateSnapshot(
+      command.payload?.targetState
+    );
+    return (
+      canonicalProjectState(expectedState) ===
+      canonicalProjectState(currentState)
+    );
+  } catch {
+    return false;
+  }
+}
+
+function canonicalProjectState(state: ProjectStateSnapshot) {
+  return JSON.stringify({
+    ...state,
+    distributionBoards: byId(state.distributionBoards),
+    circuitLists: byId(state.circuitLists),
+    circuitSections: byId(state.circuitSections),
+    circuits: byId(
+      state.circuits.map((circuit) => ({
+        ...circuit,
+        deviceRows: byId(circuit.deviceRows),
+      }))
+    ),
+    projectDevices: byId(state.projectDevices),
+    floors: byId(state.floors),
+    rooms: byId(state.rooms),
+  });
+}
+
+function byId<T extends { id: string }>(entries: readonly T[]) {
+  return [...entries].sort((left, right) =>
+    left.id.localeCompare(right.id)
+  );
+}
+
 function replaceProjectState(
   database: AppDatabase,
   state: ProjectStateSnapshot
@@ -111,8 +188,14 @@ function replaceProjectState(
     .update(projects)
     .set({
       name: state.project.name,
+      internalProjectNumber: state.project.internalProjectNumber,
+      externalProjectNumber: state.project.externalProjectNumber,
+      buildingOwner: state.project.buildingOwner,
+      description: state.project.description,
       singlePhaseVoltageV: state.project.singlePhaseVoltageV,
       threePhaseVoltageV: state.project.threePhaseVoltageV,
+      enabledDistributionBoardSupplyTypes:
+        state.project.enabledDistributionBoardSupplyTypes,
     })
     .where(eq(projects.id, state.project.id))
     .run();

src/db/repositories/project-state-snapshot.persistence.ts

@@ -32,8 +32,14 @@ export function readProjectStateSnapshot(
     .select({
       id: projects.id,
       name: projects.name,
+      internalProjectNumber: projects.internalProjectNumber,
+      externalProjectNumber: projects.externalProjectNumber,
+      buildingOwner: projects.buildingOwner,
+      description: projects.description,
       singlePhaseVoltageV: projects.singlePhaseVoltageV,
       threePhaseVoltageV: projects.threePhaseVoltageV,
+      enabledDistributionBoardSupplyTypes:
+        projects.enabledDistributionBoardSupplyTypes,
       currentRevision: projects.currentRevision,
     })
     .from(projects)
@@ -172,8 +178,14 @@ export function readProjectStateSnapshot(
     project: {
       id: project.id,
       name: project.name,
+      internalProjectNumber: project.internalProjectNumber,
+      externalProjectNumber: project.externalProjectNumber,
+      buildingOwner: project.buildingOwner,
+      description: project.description,
       singlePhaseVoltageV: project.singlePhaseVoltageV,
       threePhaseVoltageV: project.threePhaseVoltageV,
+      enabledDistributionBoardSupplyTypes:
+        project.enabledDistributionBoardSupplyTypes,
     },
     distributionBoards: boardRows,
     circuitLists: listRows,

src/db/repositories/project-transfer.repository.ts

@@ -0,0 +1,145 @@
+import crypto from "node:crypto";
+import { eq } from "drizzle-orm";
+import {
+  createProjectTransferEnvelope,
+  parseProjectTransferEnvelope,
+  remapProjectState,
+} from "../../domain/models/project-transfer.model.js";
+import { createProjectStateRestoreCommand } from "../../domain/models/project-state-restore-command.model.js";
+import type { ProjectTransferStore } from "../../domain/ports/project-transfer.store.js";
+import type { AppDatabase } from "../database-context.js";
+import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
+import { circuitLists } from "../schema/circuit-lists.js";
+import { circuitSections } from "../schema/circuit-sections.js";
+import { circuits } from "../schema/circuits.js";
+import { distributionBoards } from "../schema/distribution-boards.js";
+import { floors } from "../schema/floors.js";
+import { projectDevices } from "../schema/project-devices.js";
+import { projects } from "../schema/projects.js";
+import { rooms } from "../schema/rooms.js";
+import {
+  hashProjectStatePayload,
+  readProjectStateSnapshot,
+} from "./project-state-snapshot.persistence.js";
+import { serializeProjectStateSnapshot } from "../../domain/models/project-state-snapshot.model.js";
+
+export class ProjectTransferRepository implements ProjectTransferStore {
+  constructor(private readonly database: AppDatabase) {}
+
+  exportProject(projectId: string) {
+    const snapshot = readProjectStateSnapshot(this.database, projectId);
+    if (!snapshot) {
+      return null;
+    }
+    return createProjectTransferEnvelope(
+      new Date().toISOString(),
+      snapshot.payloadSha256,
+      snapshot.state
+    );
+  }
+
+  prepareReplace(projectId: string, value: unknown) {
+    const transfer = this.parseVerified(value);
+    const current = readProjectStateSnapshot(this.database, projectId);
+    if (!current) {
+      return null;
+    }
+    const targetState =
+      transfer.projectState.project.id === projectId
+        ? transfer.projectState
+        : remapProjectState(
+            transfer.projectState,
+            projectId,
+            () => crypto.randomUUID()
+          );
+    return {
+      command: createProjectStateRestoreCommand(
+        current.payloadSha256,
+        targetState
+      ),
+    };
+  }
+
+  importDuplicate(value: unknown) {
+    const transfer = this.parseVerified(value);
+    const projectId = crypto.randomUUID();
+    const state = remapProjectState(
+      transfer.projectState,
+      projectId,
+      () => crypto.randomUUID(),
+      `${transfer.projectState.project.name} (Kopie)`
+    );
+    this.database.transaction((tx) => insertProjectState(tx, state));
+    return { projectId, name: state.project.name };
+  }
+
+  private parseVerified(value: unknown) {
+    const rawPayloadSha256 =
+      isPlainObject(value) &&
+      isPlainObject(value.projectState)
+        ? hashProjectStatePayload(JSON.stringify(value.projectState))
+        : null;
+    const transfer = parseProjectTransferEnvelope(value);
+    const payloadJson = serializeProjectStateSnapshot(
+      transfer.projectState
+    );
+    if (
+      hashProjectStatePayload(payloadJson) !== transfer.payloadSha256 &&
+      rawPayloadSha256 !== transfer.payloadSha256
+    ) {
+      throw new Error("Project transfer checksum verification failed.");
+    }
+    return transfer;
+  }
+}
+
+function isPlainObject(value: unknown): value is Record<string, unknown> {
+  return value !== null && typeof value === "object" && !Array.isArray(value);
+}
+
+function insertProjectState(
+  database: AppDatabase,
+  state: ReturnType<typeof remapProjectState>
+) {
+  const existing = database
+    .select({ id: projects.id })
+    .from(projects)
+    .where(eq(projects.id, state.project.id))
+    .get();
+  if (existing) {
+    throw new Error("Project transfer target already exists.");
+  }
+  database
+    .insert(projects)
+    .values({ ...state.project, currentRevision: 0 })
+    .run();
+  insertMany(database, floors, state.floors);
+  insertMany(database, rooms, state.rooms);
+  insertMany(database, projectDevices, state.projectDevices);
+  insertMany(database, distributionBoards, state.distributionBoards);
+  insertMany(database, circuitLists, state.circuitLists);
+  insertMany(database, circuitSections, state.circuitSections);
+  insertMany(
+    database,
+    circuits,
+    state.circuits.map(({ deviceRows: _deviceRows, ...circuit }) => ({
+      ...circuit,
+      isReserve: circuit.isReserve ? 1 : 0,
+    }))
+  );
+  insertMany(
+    database,
+    circuitDeviceRows,
+    state.circuits.flatMap((circuit) => circuit.deviceRows)
+  );
+}
+
+function insertMany<TTable extends Parameters<AppDatabase["insert"]>[0]>(
+  database: AppDatabase,
+  table: TTable,
+  values: unknown[]
+) {
+  if (values.length > 0) {
+    database.insert(table).values(values as never).run();
+  }
+}

src/db/repositories/project-voltage.persistence.ts

@@ -0,0 +1,154 @@
+import { and, eq } from "drizzle-orm";
+import {
+  resolveCircuitPhaseType,
+  resolveProjectVoltage,
+  type ElectricalPhaseType,
+  type ProjectVoltageSettings,
+} from "../../domain/services/project-voltage.service.js";
+import type { AppDatabase } from "../database-context.js";
+import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
+import { circuitLists } from "../schema/circuit-lists.js";
+import { circuitSections } from "../schema/circuit-sections.js";
+import { circuits } from "../schema/circuits.js";
+import { projectDevices } from "../schema/project-devices.js";
+import { projects } from "../schema/projects.js";
+
+export function readProjectVoltageSettings(
+  database: AppDatabase,
+  projectId: string
+): ProjectVoltageSettings {
+  const project = database
+    .select({
+      singlePhaseVoltageV: projects.singlePhaseVoltageV,
+      threePhaseVoltageV: projects.threePhaseVoltageV,
+    })
+    .from(projects)
+    .where(eq(projects.id, projectId))
+    .get();
+  if (!project) {
+    throw new Error("Project not found.");
+  }
+  return project;
+}
+
+export function resolveProjectDeviceVoltage(
+  database: AppDatabase,
+  projectId: string,
+  phaseType: ElectricalPhaseType
+) {
+  return resolveProjectVoltage(
+    phaseType,
+    readProjectVoltageSettings(database, projectId)
+  );
+}
+
+export function resolveCircuitVoltage(
+  database: AppDatabase,
+  projectId: string,
+  sectionId: string,
+  devicePhaseTypes: ReadonlyArray<string | null | undefined> = []
+) {
+  const section = database
+    .select({ key: circuitSections.key })
+    .from(circuitSections)
+    .innerJoin(
+      circuitLists,
+      eq(circuitLists.id, circuitSections.circuitListId)
+    )
+    .where(
+      and(
+        eq(circuitSections.id, sectionId),
+        eq(circuitLists.projectId, projectId)
+      )
+    )
+    .get();
+  if (!section) {
+    throw new Error("Circuit section does not belong to project.");
+  }
+  return resolveProjectVoltage(
+    resolveCircuitPhaseType(section.key, devicePhaseTypes),
+    readProjectVoltageSettings(database, projectId)
+  );
+}
+
+export function updateDerivedCircuitVoltage(
+  database: AppDatabase,
+  projectId: string,
+  circuitId: string
+) {
+  const circuit = database
+    .select({
+      id: circuits.id,
+      sectionId: circuits.sectionId,
+    })
+    .from(circuits)
+    .innerJoin(circuitLists, eq(circuitLists.id, circuits.circuitListId))
+    .where(
+      and(
+        eq(circuits.id, circuitId),
+        eq(circuitLists.projectId, projectId)
+      )
+    )
+    .get();
+  if (!circuit) {
+    throw new Error("Circuit does not belong to project.");
+  }
+  const devicePhaseTypes = database
+    .select({ phaseType: circuitDeviceRows.phaseType })
+    .from(circuitDeviceRows)
+    .where(eq(circuitDeviceRows.circuitId, circuitId))
+    .all()
+    .map((row) => row.phaseType);
+  const voltage = resolveCircuitVoltage(
+    database,
+    projectId,
+    circuit.sectionId,
+    devicePhaseTypes
+  );
+  database
+    .update(circuits)
+    .set({ voltage })
+    .where(eq(circuits.id, circuitId))
+    .run();
+  return voltage;
+}
+
+export function updateAllDerivedProjectVoltages(
+  database: AppDatabase,
+  projectId: string
+) {
+  const settings = readProjectVoltageSettings(database, projectId);
+  const devices = database
+    .select({
+      id: projectDevices.id,
+      phaseType: projectDevices.phaseType,
+    })
+    .from(projectDevices)
+    .where(eq(projectDevices.projectId, projectId))
+    .all();
+  for (const device of devices) {
+    if (
+      device.phaseType !== "single_phase" &&
+      device.phaseType !== "three_phase"
+    ) {
+      throw new Error("Persisted project-device phase type is invalid.");
+    }
+    database
+      .update(projectDevices)
+      .set({
+        voltageV: resolveProjectVoltage(device.phaseType, settings),
+      })
+      .where(eq(projectDevices.id, device.id))
+      .run();
+  }
+
+  const projectCircuits = database
+    .select({ id: circuits.id })
+    .from(circuits)
+    .innerJoin(circuitLists, eq(circuitLists.id, circuits.circuitListId))
+    .where(eq(circuitLists.projectId, projectId))
+    .all();
+  for (const circuit of projectCircuits) {
+    updateDerivedCircuitVoltage(database, projectId, circuit.id);
+  }
+}

src/db/repositories/project.repository.ts

@@ -5,6 +5,7 @@ import { projects } from "../schema/projects.js";
 import type {
   CreateProjectInput,
 } from "../../shared/validation/project-structure.schemas.js";
+import { defaultDistributionBoardSupplyTypes } from "../../shared/constants/distribution-board.js";
 
 export class ProjectRepository {
   constructor(private readonly database: AppDatabase) {}
@@ -20,8 +21,15 @@ export class ProjectRepository {
     const project = {
       id,
       name: input.name,
+      internalProjectNumber: input.internalProjectNumber ?? null,
+      externalProjectNumber: input.externalProjectNumber ?? null,
+      buildingOwner: input.buildingOwner ?? null,
+      description: input.description ?? null,
       singlePhaseVoltageV: input.singlePhaseVoltageV ?? 230,
       threePhaseVoltageV: input.threePhaseVoltageV ?? 400,
+      enabledDistributionBoardSupplyTypes: [
+        ...defaultDistributionBoardSupplyTypes,
+      ],
       currentRevision: 0,
     };
     await db.insert(projects).values(project);

src/db/schema/distribution-boards.ts

@@ -1,5 +1,7 @@
-import { sqliteTable, text } from "drizzle-orm/sqlite-core";
+import { real, sqliteTable, text } from "drizzle-orm/sqlite-core";
+import { floors } from "./floors.js";
 import { projects } from "./projects.js";
+import type { DistributionBoardSupplyType } from "../../shared/constants/distribution-board.js";
 
 export const distributionBoards = sqliteTable("distribution_boards", {
   id: text("id").primaryKey(),
@@ -7,5 +9,12 @@ export const distributionBoards = sqliteTable("distribution_boards", {
     .notNull()
     .references(() => projects.id, { onDelete: "cascade" }),
   name: text("name").notNull(),
+  floorId: text("floor_id").references(() => floors.id, {
+    onDelete: "set null",
+  }),
+  supplyType: text("supply_type").$type<DistributionBoardSupplyType>(),
+  simultaneityFactor: real("simultaneity_factor")
+    .notNull()
+    .default(1),
 });
 

src/db/schema/projects.ts

@@ -1,9 +1,22 @@
+import { sql } from "drizzle-orm";
 import { integer, sqliteTable, text } from "drizzle-orm/sqlite-core";
+import type { DistributionBoardSupplyType } from "../../shared/constants/distribution-board.js";
 
 export const projects = sqliteTable("projects", {
   id: text("id").primaryKey(),
   name: text("name").notNull(),
+  internalProjectNumber: text("internal_project_number"),
+  externalProjectNumber: text("external_project_number"),
+  buildingOwner: text("building_owner"),
+  description: text("description"),
   singlePhaseVoltageV: integer("single_phase_voltage_v").notNull().default(230),
   threePhaseVoltageV: integer("three_phase_voltage_v").notNull().default(400),
+  enabledDistributionBoardSupplyTypes: text(
+    "enabled_distribution_board_supply_types",
+    { mode: "json" }
+  )
+    .$type<DistributionBoardSupplyType[]>()
+    .notNull()
+    .default(sql`'["AV","SV","EV","USV","MSR","SiBe"]'`),
   currentRevision: integer("current_revision").notNull().default(0),
 });

src/domain/calculations/circuit-power-calculation.ts

@@ -15,3 +15,37 @@ export function calculateCircuitTotalPower(
   );
 }
 
+export function calculateSectionTotalPower(
+  circuits: Array<{ circuitTotalPower: number }>
+): number {
+  return circuits.reduce(
+    (sum, circuit) => sum + circuit.circuitTotalPower,
+    0
+  );
+}
+
+export function calculateDistributionBoardTotalPower(
+  sections: Array<{ sectionTotalPower: number }>
+): number {
+  return sections.reduce(
+    (sum, section) => sum + section.sectionTotalPower,
+    0
+  );
+}
+
+export function applyDistributionBoardSimultaneityFactor(
+  totalPower: number,
+  simultaneityFactor: number
+): number {
+  if (
+    !Number.isFinite(simultaneityFactor) ||
+    simultaneityFactor < 0 ||
+    simultaneityFactor > 1
+  ) {
+    throw new Error(
+      "Distribution-board simultaneity factor must be between zero and one."
+    );
+  }
+  return totalPower * simultaneityFactor;
+}
+

src/domain/models/circuit-tree.model.ts

@@ -52,12 +52,18 @@ export interface CircuitTreeSectionBlock {
   displayName: string;
   prefix: string;
   sortOrder: number;
+  sectionTotalPower: number;
   circuits: CircuitTreeCircuit[];
 }
 
 export interface CircuitTreeResponse {
   circuitListId: string;
   currentRevision: number;
+  singlePhaseVoltageV: number;
+  threePhaseVoltageV: number;
+  distributionBoardSimultaneityFactor: number;
+  distributionBoardTotalPower: number;
+  distributionBoardTotalPowerWithSimultaneityFactor: number;
   sections: CircuitTreeSectionBlock[];
 }
 

src/domain/models/distribution-board-project-command.model.ts

@@ -0,0 +1,141 @@
+import {
+  distributionBoardSupplyTypes,
+  type DistributionBoardSupplyType,
+} from "../../shared/constants/distribution-board.js";
+import type { SerializedProjectCommand } from "./project-command.model.js";
+
+export const distributionBoardUpdateCommandType =
+  "distribution-board.update" as const;
+export const legacyDistributionBoardUpdateCommandSchemaVersion = 1 as const;
+export const distributionBoardUpdateCommandSchemaVersion = 2 as const;
+
+export interface DistributionBoardUpdateValues {
+  floorId: string | null;
+  supplyType: DistributionBoardSupplyType | null;
+  simultaneityFactor: number;
+}
+
+export type DistributionBoardUpdateField =
+  keyof DistributionBoardUpdateValues;
+export type DistributionBoardUpdatePatch =
+  Partial<DistributionBoardUpdateValues>;
+
+export interface DistributionBoardUpdateFieldChange<
+  TField extends DistributionBoardUpdateField =
+    DistributionBoardUpdateField,
+> {
+  field: TField;
+  value: DistributionBoardUpdateValues[TField];
+}
+
+export interface DistributionBoardUpdateCommandPayload {
+  distributionBoardId: string;
+  changes: DistributionBoardUpdateFieldChange[];
+}
+
+interface CurrentDistributionBoardUpdateProjectCommand
+  extends SerializedProjectCommand<DistributionBoardUpdateCommandPayload> {
+  schemaVersion: typeof distributionBoardUpdateCommandSchemaVersion;
+  type: typeof distributionBoardUpdateCommandType;
+}
+
+interface LegacyDistributionBoardUpdateProjectCommand
+  extends SerializedProjectCommand<DistributionBoardUpdateCommandPayload> {
+  schemaVersion: typeof legacyDistributionBoardUpdateCommandSchemaVersion;
+  type: typeof distributionBoardUpdateCommandType;
+}
+
+export type DistributionBoardUpdateProjectCommand =
+  | CurrentDistributionBoardUpdateProjectCommand
+  | LegacyDistributionBoardUpdateProjectCommand;
+
+export function createDistributionBoardUpdateProjectCommand(
+  distributionBoardId: string,
+  patch: DistributionBoardUpdatePatch
+): CurrentDistributionBoardUpdateProjectCommand {
+  const command: CurrentDistributionBoardUpdateProjectCommand = {
+    schemaVersion: distributionBoardUpdateCommandSchemaVersion,
+    type: distributionBoardUpdateCommandType,
+    payload: {
+      distributionBoardId,
+      changes: Object.entries(patch).map(([field, value]) => ({
+        field: field as DistributionBoardUpdateField,
+        value,
+      })) as DistributionBoardUpdateFieldChange[],
+    },
+  };
+  assertDistributionBoardUpdateProjectCommand(command);
+  return command;
+}
+
+export function assertDistributionBoardUpdateProjectCommand(
+  command: SerializedProjectCommand<unknown>
+): asserts command is DistributionBoardUpdateProjectCommand {
+  if (
+    (command.schemaVersion !==
+      legacyDistributionBoardUpdateCommandSchemaVersion &&
+      command.schemaVersion !== distributionBoardUpdateCommandSchemaVersion) ||
+    command.type !== distributionBoardUpdateCommandType ||
+    !isPlainObject(command.payload)
+  ) {
+    throw new Error("Unsupported distribution-board update command.");
+  }
+  const { distributionBoardId, changes } = command.payload;
+  if (
+    typeof distributionBoardId !== "string" ||
+    !distributionBoardId.trim() ||
+    !Array.isArray(changes) ||
+    changes.length === 0
+  ) {
+    throw new Error(
+      "Distribution-board update command requires an id and changes."
+    );
+  }
+  const seen = new Set<string>();
+  for (const change of changes) {
+    if (
+      !isPlainObject(change) ||
+      (change.field !== "floorId" &&
+        change.field !== "supplyType" &&
+        (command.schemaVersion ===
+          legacyDistributionBoardUpdateCommandSchemaVersion ||
+          change.field !== "simultaneityFactor")) ||
+      seen.has(change.field)
+    ) {
+      throw new Error(
+        "Distribution-board update contains an invalid or duplicate field."
+      );
+    }
+    if (change.field === "floorId") {
+      if (
+        change.value !== null &&
+        (typeof change.value !== "string" || !change.value.trim())
+      ) {
+        throw new Error("floorId must be a non-empty string or null.");
+      }
+    } else if (change.field === "supplyType") {
+      if (
+        change.value !== null &&
+        !distributionBoardSupplyTypes.includes(
+          change.value as DistributionBoardSupplyType
+        )
+      ) {
+        throw new Error("supplyType is invalid.");
+      }
+    } else if (
+      typeof change.value !== "number" ||
+      !Number.isFinite(change.value) ||
+      change.value < 0 ||
+      change.value > 1
+    ) {
+      throw new Error(
+        "simultaneityFactor must be between zero and one."
+      );
+    }
+    seen.add(change.field);
+  }
+}
+
+function isPlainObject(value: unknown): value is Record<string, unknown> {
+  return value !== null && typeof value === "object" && !Array.isArray(value);
+}

src/domain/models/distribution-board-structure-project-command.model.ts

@@ -1,11 +1,16 @@
 import crypto from "node:crypto";
+import {
+  distributionBoardSupplyTypes,
+  type DistributionBoardSupplyType,
+} from "../../shared/constants/distribution-board.js";
 import type { SerializedProjectCommand } from "./project-command.model.js";
 
 export const distributionBoardInsertCommandType =
   "distribution-board.insert" as const;
 export const distributionBoardDeleteCommandType =
   "distribution-board.delete" as const;
-export const distributionBoardStructureCommandSchemaVersion = 1 as const;
+export const legacyDistributionBoardStructureCommandSchemaVersion = 1 as const;
+export const distributionBoardStructureCommandSchemaVersion = 2 as const;
 
 export const defaultCircuitSectionDefinitions = [
   {
@@ -34,11 +39,23 @@ export const defaultCircuitSectionDefinitions = [
   },
 ] as const;
 
+interface LegacyDistributionBoardStructureSnapshot {
+  distributionBoard: {
+    id: string;
+    projectId: string;
+    name: string;
+  };
+  circuitList: DistributionBoardStructureSnapshot["circuitList"];
+  sections: DistributionBoardStructureSnapshot["sections"];
+}
+
 export interface DistributionBoardStructureSnapshot {
   distributionBoard: {
     id: string;
     projectId: string;
     name: string;
+    floorId: string | null;
+    supplyType: DistributionBoardSupplyType | null;
   };
   circuitList: {
     id: string;
@@ -56,29 +73,52 @@ export interface DistributionBoardStructureSnapshot {
   }>;
 }
 
-interface DistributionBoardStructureCommandPayload {
+interface DistributionBoardStructureCommandPayload<
-  structure: DistributionBoardStructureSnapshot;
+  TStructure = DistributionBoardStructureSnapshot,
+> {
+  structure: TStructure;
+}
+
+interface CurrentDistributionBoardStructureProjectCommand
+  extends SerializedProjectCommand<DistributionBoardStructureCommandPayload> {
+  schemaVersion: typeof distributionBoardStructureCommandSchemaVersion;
+  type:
+    | typeof distributionBoardInsertCommandType
+    | typeof distributionBoardDeleteCommandType;
+}
+
+interface LegacyDistributionBoardStructureProjectCommand
+  extends SerializedProjectCommand<
+    DistributionBoardStructureCommandPayload<LegacyDistributionBoardStructureSnapshot>
+  > {
+  schemaVersion: typeof legacyDistributionBoardStructureCommandSchemaVersion;
+  type:
+    | typeof distributionBoardInsertCommandType
+    | typeof distributionBoardDeleteCommandType;
 }
 
 export interface DistributionBoardInsertProjectCommand
-  extends SerializedProjectCommand<DistributionBoardStructureCommandPayload> {
+  extends CurrentDistributionBoardStructureProjectCommand {
-  schemaVersion: typeof distributionBoardStructureCommandSchemaVersion;
   type: typeof distributionBoardInsertCommandType;
 }
 
 export interface DistributionBoardDeleteProjectCommand
-  extends SerializedProjectCommand<DistributionBoardStructureCommandPayload> {
+  extends CurrentDistributionBoardStructureProjectCommand {
-  schemaVersion: typeof distributionBoardStructureCommandSchemaVersion;
   type: typeof distributionBoardDeleteCommandType;
 }
 
 export type DistributionBoardStructureProjectCommand =
   | DistributionBoardInsertProjectCommand
-  | DistributionBoardDeleteProjectCommand;
+  | DistributionBoardDeleteProjectCommand
+  | LegacyDistributionBoardStructureProjectCommand;
 
 export function createDistributionBoardStructureSnapshot(
   projectId: string,
-  name: string
+  name: string,
+  input: {
+    floorId?: string | null;
+    supplyType?: DistributionBoardSupplyType | null;
+  } = {}
 ): DistributionBoardStructureSnapshot {
   const normalizedName = name.trim();
   assertNonEmptyString(projectId, "projectId");
@@ -89,6 +129,8 @@ export function createDistributionBoardStructureSnapshot(
       id: structureId,
       projectId,
       name: normalizedName,
+      floorId: input.floorId ?? null,
+      supplyType: input.supplyType ?? null,
     },
     circuitList: {
       id: structureId,
@@ -132,7 +174,7 @@ export function createDistributionBoardDeleteProjectCommand(
 
 export function assertDistributionBoardInsertProjectCommand(
   command: SerializedProjectCommand<unknown>
-): asserts command is DistributionBoardInsertProjectCommand {
+): asserts command is DistributionBoardStructureProjectCommand {
   assertDistributionBoardStructureProjectCommand(
     command,
     distributionBoardInsertCommandType
@@ -141,23 +183,88 @@ export function assertDistributionBoardInsertProjectCommand(
 
 export function assertDistributionBoardDeleteProjectCommand(
   command: SerializedProjectCommand<unknown>
-): asserts command is DistributionBoardDeleteProjectCommand {
+): asserts command is DistributionBoardStructureProjectCommand {
   assertDistributionBoardStructureProjectCommand(
     command,
     distributionBoardDeleteCommandType
   );
 }
 
+export function normalizeDistributionBoardStructureProjectCommand(
+  command: DistributionBoardStructureProjectCommand
+): DistributionBoardInsertProjectCommand | DistributionBoardDeleteProjectCommand {
+  if (
+    command.schemaVersion ===
+    legacyDistributionBoardStructureCommandSchemaVersion
+  ) {
+    const structure: DistributionBoardStructureSnapshot = {
+      ...command.payload.structure,
+      distributionBoard: {
+        ...command.payload.structure.distributionBoard,
+        floorId: null,
+        supplyType: null,
+      },
+    };
+    return command.type === distributionBoardInsertCommandType
+      ? createDistributionBoardInsertProjectCommand(structure)
+      : createDistributionBoardDeleteProjectCommand(structure);
+  }
+  return command as
+    | DistributionBoardInsertProjectCommand
+    | DistributionBoardDeleteProjectCommand;
+}
+
 export function assertDistributionBoardStructureSnapshot(
   structure: unknown
 ): asserts structure is DistributionBoardStructureSnapshot {
+  assertDistributionBoardStructureSnapshotVersion(structure, false);
+}
+
+function assertDistributionBoardStructureProjectCommand(
+  command: SerializedProjectCommand<unknown>,
+  expectedType:
+    | typeof distributionBoardInsertCommandType
+    | typeof distributionBoardDeleteCommandType
+) {
+  if (
+    command.type !== expectedType ||
+    !isPlainObject(command.payload) ||
+    Object.keys(command.payload).length !== 1
+  ) {
+    throw new Error("Unsupported distribution-board structure command.");
+  }
+  if (
+    command.schemaVersion ===
+    legacyDistributionBoardStructureCommandSchemaVersion
+  ) {
+    assertDistributionBoardStructureSnapshotVersion(
+      command.payload.structure,
+      true
+    );
+    return;
+  }
+  if (
+    command.schemaVersion !== distributionBoardStructureCommandSchemaVersion
+  ) {
+    throw new Error("Unsupported distribution-board structure command.");
+  }
+  assertDistributionBoardStructureSnapshotVersion(
+    command.payload.structure,
+    false
+  );
+}
+
+function assertDistributionBoardStructureSnapshotVersion(
+  structure: unknown,
+  legacy: boolean
+) {
   if (!isPlainObject(structure) || Object.keys(structure).length !== 3) {
     throw new Error("Distribution-board structure is invalid.");
   }
   const { distributionBoard, circuitList, sections } = structure;
   if (
     !isPlainObject(distributionBoard) ||
-    Object.keys(distributionBoard).length !== 3 ||
+    Object.keys(distributionBoard).length !== (legacy ? 3 : 5) ||
     !isPlainObject(circuitList) ||
     Object.keys(circuitList).length !== 4 ||
     !Array.isArray(sections) ||
@@ -165,8 +272,15 @@ export function assertDistributionBoardStructureSnapshot(
   ) {
     throw new Error("Distribution-board structure is incomplete.");
   }
-  for (const [field, value] of Object.entries(distributionBoard)) {
+  for (const field of ["id", "projectId", "name"] as const) {
-    assertNonEmptyString(value, `distributionBoard.${field}`);
+    assertNonEmptyString(
+      distributionBoard[field],
+      `distributionBoard.${field}`
+    );
+  }
+  if (!legacy) {
+    assertNullableId(distributionBoard.floorId, "distributionBoard.floorId");
+    assertNullableSupplyType(distributionBoard.supplyType);
   }
   for (const [field, value] of Object.entries(circuitList)) {
     assertNonEmptyString(value, `circuitList.${field}`);
@@ -174,22 +288,16 @@ export function assertDistributionBoardStructureSnapshot(
   if (
     circuitList.projectId !== distributionBoard.projectId ||
     circuitList.distributionBoardId !== distributionBoard.id ||
-    circuitList.name !==
+    circuitList.name !== `${distributionBoard.name} Stromkreisliste`
-      `${distributionBoard.name} Stromkreisliste`
   ) {
-    throw new Error(
+    throw new Error("Distribution board and circuit list are inconsistent.");
-      "Distribution board and circuit list are inconsistent."
-    );
   }
 
   const sectionIds = new Set<string>();
   for (let index = 0; index < sections.length; index += 1) {
     const section = sections[index];
     const expected = defaultCircuitSectionDefinitions[index];
-    if (
+    if (!isPlainObject(section) || Object.keys(section).length !== 6) {
-      !isPlainObject(section) ||
-      Object.keys(section).length !== 6
-    ) {
       throw new Error("Default circuit section is invalid.");
     }
     assertNonEmptyString(section.id, "section.id");
@@ -211,22 +319,23 @@ export function assertDistributionBoardStructureSnapshot(
   }
 }
 
-function assertDistributionBoardStructureProjectCommand(
+function assertNullableId(value: unknown, field: string) {
-  command: SerializedProjectCommand<unknown>,
+  if (value !== null) {
-  expectedType:
+    assertNonEmptyString(value, field);
-    | typeof distributionBoardInsertCommandType
+  }
-    | typeof distributionBoardDeleteCommandType
+}
-) {
+
-  if (
+function assertNullableSupplyType(
-    command.schemaVersion !==
+  value: unknown
-      distributionBoardStructureCommandSchemaVersion ||
+): asserts value is DistributionBoardSupplyType | null {
-    command.type !== expectedType ||
+  if (
-    !isPlainObject(command.payload) ||
+    value !== null &&
-    Object.keys(command.payload).length !== 1
+    !distributionBoardSupplyTypes.includes(
-  ) {
+      value as DistributionBoardSupplyType
-    throw new Error("Unsupported distribution-board structure command.");
+    )
+  ) {
+    throw new Error("distributionBoard.supplyType is invalid.");
   }
-  assertDistributionBoardStructureSnapshot(command.payload.structure);
 }
 
 function assertNonEmptyString(

src/domain/models/project-settings-project-command.model.ts

@@ -1,24 +1,59 @@
 import type { SerializedProjectCommand } from "./project-command.model.js";
+import {
+  distributionBoardSupplyTypes,
+  type DistributionBoardSupplyType,
+} from "../../shared/constants/distribution-board.js";
 
 export const projectSettingsUpdateCommandType =
   "project.update-settings" as const;
-export const projectSettingsUpdateCommandSchemaVersion = 1 as const;
+export const legacyProjectSettingsUpdateCommandSchemaVersion = 1 as const;
+export const previousProjectSettingsUpdateCommandSchemaVersion = 2 as const;
+export const projectSettingsUpdateCommandSchemaVersion = 3 as const;
 
-export interface ProjectSettingsValues {
+export interface LegacyProjectSettingsValues {
   singlePhaseVoltageV: number;
   threePhaseVoltageV: number;
 }
 
-export interface ProjectSettingsUpdateProjectCommand
+export interface PreviousProjectSettingsValues extends LegacyProjectSettingsValues {
+  name: string;
+  internalProjectNumber: string | null;
+  externalProjectNumber: string | null;
+  buildingOwner: string | null;
+  description: string | null;
+}
+
+export interface ProjectSettingsValues extends PreviousProjectSettingsValues {
+  enabledDistributionBoardSupplyTypes: DistributionBoardSupplyType[];
+}
+
+export interface LegacyProjectSettingsUpdateProjectCommand
+  extends SerializedProjectCommand<LegacyProjectSettingsValues> {
+  schemaVersion: typeof legacyProjectSettingsUpdateCommandSchemaVersion;
+  type: typeof projectSettingsUpdateCommandType;
+}
+
+export interface CurrentProjectSettingsUpdateProjectCommand
   extends SerializedProjectCommand<ProjectSettingsValues> {
   schemaVersion: typeof projectSettingsUpdateCommandSchemaVersion;
   type: typeof projectSettingsUpdateCommandType;
 }
 
+export interface PreviousProjectSettingsUpdateProjectCommand
+  extends SerializedProjectCommand<PreviousProjectSettingsValues> {
+  schemaVersion: typeof previousProjectSettingsUpdateCommandSchemaVersion;
+  type: typeof projectSettingsUpdateCommandType;
+}
+
+export type ProjectSettingsUpdateProjectCommand =
+  | LegacyProjectSettingsUpdateProjectCommand
+  | PreviousProjectSettingsUpdateProjectCommand
+  | CurrentProjectSettingsUpdateProjectCommand;
+
 export function createProjectSettingsUpdateProjectCommand(
   values: ProjectSettingsValues
-): ProjectSettingsUpdateProjectCommand {
+): CurrentProjectSettingsUpdateProjectCommand {
-  const command: ProjectSettingsUpdateProjectCommand = {
+  const command: CurrentProjectSettingsUpdateProjectCommand = {
     schemaVersion: projectSettingsUpdateCommandSchemaVersion,
     type: projectSettingsUpdateCommandType,
     payload: { ...values },
@@ -31,16 +66,100 @@ export function assertProjectSettingsUpdateProjectCommand(
   command: SerializedProjectCommand<unknown>
 ): asserts command is ProjectSettingsUpdateProjectCommand {
   if (
-    command.schemaVersion !== projectSettingsUpdateCommandSchemaVersion ||
+    command.type !== projectSettingsUpdateCommandType ||
-    command.type !== projectSettingsUpdateCommandType
+    (command.schemaVersion !==
+      legacyProjectSettingsUpdateCommandSchemaVersion &&
+      command.schemaVersion !==
+        previousProjectSettingsUpdateCommandSchemaVersion &&
+      command.schemaVersion !== projectSettingsUpdateCommandSchemaVersion)
   ) {
     throw new Error("Unsupported project settings update command.");
   }
+  if (!isPlainObject(command.payload)) {
+    throw new Error(
+      "Project settings update command contains invalid values."
+    );
+  }
+  if (command.schemaVersion === legacyProjectSettingsUpdateCommandSchemaVersion) {
+    assertLegacyValues(command.payload);
+    return;
+  }
+  const expectedKeyCount =
+    command.schemaVersion === previousProjectSettingsUpdateCommandSchemaVersion
+      ? 7
+      : 8;
   if (
-    !isPlainObject(command.payload) ||
+    !isTrimmedString(command.payload.name, 1, 200) ||
+    !isNullableTrimmedString(command.payload.internalProjectNumber, 100) ||
+    !isNullableTrimmedString(command.payload.externalProjectNumber, 100) ||
+    !isNullableTrimmedString(command.payload.buildingOwner, 200) ||
+    !isNullableTrimmedString(command.payload.description, 2000) ||
     !isPositiveFiniteNumber(command.payload.singlePhaseVoltageV) ||
     !isPositiveFiniteNumber(command.payload.threePhaseVoltageV) ||
-    Object.keys(command.payload).length !== 2
+    Object.keys(command.payload).length !== expectedKeyCount
+  ) {
+    throw new Error(
+      "Project settings update command contains invalid values."
+    );
+  }
+  if (
+    command.schemaVersion === projectSettingsUpdateCommandSchemaVersion &&
+    !isValidSupplyTypes(
+      command.payload.enabledDistributionBoardSupplyTypes
+    )
+  ) {
+    throw new Error(
+      "Project settings update command contains invalid supply types."
+    );
+  }
+}
+
+export function normalizeProjectSettingsValues(
+  command: ProjectSettingsUpdateProjectCommand,
+  current: ProjectSettingsValues
+): ProjectSettingsValues {
+  if (command.schemaVersion === legacyProjectSettingsUpdateCommandSchemaVersion) {
+    return {
+      ...current,
+      ...command.payload,
+    };
+  }
+  if (
+    command.schemaVersion === previousProjectSettingsUpdateCommandSchemaVersion
+  ) {
+    return {
+      ...command.payload,
+      enabledDistributionBoardSupplyTypes:
+        current.enabledDistributionBoardSupplyTypes,
+    };
+  }
+  return command.payload;
+}
+
+function isValidSupplyTypes(
+  value: unknown
+): value is DistributionBoardSupplyType[] {
+  return (
+    Array.isArray(value) &&
+    value.length > 0 &&
+    new Set(value).size === value.length &&
+    value.every(
+      (entry) =>
+        typeof entry === "string" &&
+        distributionBoardSupplyTypes.includes(
+          entry as DistributionBoardSupplyType
+        )
+    )
+  );
+}
+
+function assertLegacyValues(
+  payload: Record<string, unknown>
+): asserts payload is Record<string, unknown> & LegacyProjectSettingsValues {
+  if (
+    !isPositiveFiniteNumber(payload.singlePhaseVoltageV) ||
+    !isPositiveFiniteNumber(payload.threePhaseVoltageV) ||
+    Object.keys(payload).length !== 2
   ) {
     throw new Error(
       "Project settings update command contains invalid voltages."
@@ -59,3 +178,26 @@ function isPositiveFiniteNumber(value: unknown): value is number {
 function isPlainObject(value: unknown): value is Record<string, unknown> {
   return value !== null && typeof value === "object" && !Array.isArray(value);
 }
+
+function isTrimmedString(
+  value: unknown,
+  minimumLength: number,
+  maximumLength: number
+): value is string {
+  return (
+    typeof value === "string" &&
+    value === value.trim() &&
+    value.length >= minimumLength &&
+    value.length <= maximumLength
+  );
+}
+
+function isNullableTrimmedString(
+  value: unknown,
+  maximumLength: number
+): value is string | null {
+  return (
+    value === null ||
+    (isTrimmedString(value, 1, maximumLength))
+  );
+}

src/domain/models/project-state-snapshot.model.ts

@@ -1,12 +1,26 @@
 import { z } from "zod";
+import {
+  defaultDistributionBoardSupplyTypes,
+  distributionBoardSupplyTypes,
+} from "../../shared/constants/distribution-board.js";
+import {
+  resolveCircuitPhaseType,
+  resolveProjectVoltage,
+  normalizeKnownElectricalPhaseType,
+} from "../services/project-voltage.service.js";
 
-export const projectStateSnapshotSchemaVersion = 1 as const;
+export const legacyProjectStateSnapshotSchemaVersion = 1 as const;
+export const previousProjectStateSnapshotSchemaVersion = 2 as const;
+export const distributionBoardProjectStateSnapshotSchemaVersion = 3 as const;
+export const supplyTypesProjectStateSnapshotSchemaVersion = 4 as const;
+export const voltageProjectStateSnapshotSchemaVersion = 5 as const;
+export const projectStateSnapshotSchemaVersion = 6 as const;
 
 const idSchema = z.string().trim().min(1);
 const nullableStringSchema = z.string().nullable();
 const finiteNumberSchema = z.number().finite();
 
-const projectSchema = z
+const legacyProjectSchema = z
   .object({
     id: idSchema,
     name: z.string().trim().min(1),
@@ -15,7 +29,21 @@ const projectSchema = z
   })
   .strict();
 
-const distributionBoardSchema = z
+const projectSchema = legacyProjectSchema.extend({
+  internalProjectNumber: z.string().trim().min(1).max(100).nullable(),
+  externalProjectNumber: z.string().trim().min(1).max(100).nullable(),
+  buildingOwner: z.string().trim().min(1).max(200).nullable(),
+  description: z.string().trim().min(1).max(2000).nullable(),
+});
+
+const currentProjectSchema = projectSchema.extend({
+  enabledDistributionBoardSupplyTypes: z
+    .array(z.enum(distributionBoardSupplyTypes))
+    .min(1)
+    .refine((values) => new Set(values).size === values.length),
+});
+
+const legacyDistributionBoardSchema = z
   .object({
     id: idSchema,
     projectId: idSchema,
@@ -23,6 +51,19 @@ const distributionBoardSchema = z
   })
   .strict();
 
+const distributionBoardSchema = legacyDistributionBoardSchema
+  .extend({
+    floorId: idSchema.nullable(),
+    supplyType: z.enum(distributionBoardSupplyTypes).nullable(),
+  })
+  .strict();
+
+const currentDistributionBoardSchema = distributionBoardSchema
+  .extend({
+    simultaneityFactor: finiteNumberSchema.min(0).max(1),
+  })
+  .strict();
+
 const circuitListSchema = z
   .object({
     id: idSchema,
@@ -132,20 +173,66 @@ const roomSchema = z
   })
   .strict();
 
-export const projectStateSnapshotSchema = z
+const commonProjectStateSnapshotContents = {
-  .object({
-    schemaVersion: z.literal(projectStateSnapshotSchemaVersion),
-    project: projectSchema,
-    distributionBoards: z.array(distributionBoardSchema),
   circuitLists: z.array(circuitListSchema),
   circuitSections: z.array(circuitSectionSchema),
   circuits: z.array(circuitSchema),
   projectDevices: z.array(projectDeviceSchema),
   floors: z.array(floorSchema),
   rooms: z.array(roomSchema),
+};
+
+const legacyProjectStateSnapshotSchema = z
+  .object({
+    schemaVersion: z.literal(legacyProjectStateSnapshotSchemaVersion),
+    project: legacyProjectSchema,
+    distributionBoards: z.array(legacyDistributionBoardSchema),
+    ...commonProjectStateSnapshotContents,
   })
   .strict();
 
+const previousProjectStateSnapshotSchema = z
+  .object({
+    schemaVersion: z.literal(previousProjectStateSnapshotSchemaVersion),
+    project: projectSchema,
+    distributionBoards: z.array(legacyDistributionBoardSchema),
+    ...commonProjectStateSnapshotContents,
+  })
+  .strict();
+
+const distributionBoardProjectStateSnapshotSchema = z
+  .object({
+    schemaVersion: z.literal(
+      distributionBoardProjectStateSnapshotSchemaVersion
+    ),
+    project: projectSchema,
+    distributionBoards: z.array(distributionBoardSchema),
+    ...commonProjectStateSnapshotContents,
+  })
+  .strict();
+
+const supplyTypesProjectStateSnapshotSchema = z
+  .object({
+    schemaVersion: z.literal(supplyTypesProjectStateSnapshotSchemaVersion),
+    project: currentProjectSchema,
+    distributionBoards: z.array(distributionBoardSchema),
+    ...commonProjectStateSnapshotContents,
+  })
+  .strict();
+
+const voltageProjectStateSnapshotSchema =
+  supplyTypesProjectStateSnapshotSchema.extend({
+    schemaVersion: z.literal(
+      voltageProjectStateSnapshotSchemaVersion
+    ),
+  });
+
+export const projectStateSnapshotSchema =
+  voltageProjectStateSnapshotSchema.extend({
+    schemaVersion: z.literal(projectStateSnapshotSchemaVersion),
+    distributionBoards: z.array(currentDistributionBoardSchema),
+  });
+
 export type ProjectStateSnapshot = z.infer<
   typeof projectStateSnapshotSchema
 >;
@@ -153,11 +240,193 @@ export type ProjectStateSnapshot = z.infer<
 export function parseProjectStateSnapshot(
   value: unknown
 ): ProjectStateSnapshot {
-  const snapshot = projectStateSnapshotSchema.parse(value);
+  const version = isPlainObject(value) ? value.schemaVersion : undefined;
+  const parsedSnapshot =
+    version === legacyProjectStateSnapshotSchemaVersion
+      ? upgradeVoltageProjectStateSnapshot(
+          upgradeSupplyTypesProjectStateSnapshot(
+            upgradeDistributionBoardProjectStateSnapshot(
+              upgradePreviousProjectStateSnapshot(
+                upgradeLegacyProjectStateSnapshot(
+                  legacyProjectStateSnapshotSchema.parse(value)
+                )
+              )
+            )
+          )
+        )
+      : version === previousProjectStateSnapshotSchemaVersion
+        ? upgradeVoltageProjectStateSnapshot(
+            upgradeSupplyTypesProjectStateSnapshot(
+              upgradeDistributionBoardProjectStateSnapshot(
+                upgradePreviousProjectStateSnapshot(
+                  previousProjectStateSnapshotSchema.parse(value)
+                )
+              )
+            )
+          )
+        : version === distributionBoardProjectStateSnapshotSchemaVersion
+          ? upgradeVoltageProjectStateSnapshot(
+              upgradeSupplyTypesProjectStateSnapshot(
+                upgradeDistributionBoardProjectStateSnapshot(
+                  distributionBoardProjectStateSnapshotSchema.parse(value)
+                )
+              )
+            )
+          : version === supplyTypesProjectStateSnapshotSchemaVersion
+            ? upgradeVoltageProjectStateSnapshot(
+                upgradeSupplyTypesProjectStateSnapshot(
+                  supplyTypesProjectStateSnapshotSchema.parse(value)
+                )
+              )
+            : version === voltageProjectStateSnapshotSchemaVersion
+              ? upgradeVoltageProjectStateSnapshot(
+                  voltageProjectStateSnapshotSchema.parse(value)
+                )
+              : projectStateSnapshotSchema.parse(value);
+  const snapshot = normalizeSnapshotPhaseTypes(parsedSnapshot);
   assertProjectStateSnapshotRelations(snapshot);
   return snapshot;
 }
 
+function normalizeSnapshotPhaseTypes(
+  snapshot: ProjectStateSnapshot
+): ProjectStateSnapshot {
+  const sectionById = new Map(
+    snapshot.circuitSections.map((section) => [section.id, section])
+  );
+  const projectDeviceById = new Map(
+    snapshot.projectDevices.map((device) => [device.id, device])
+  );
+  return {
+    ...snapshot,
+    circuits: snapshot.circuits.map((circuit) => {
+      const section = sectionById.get(circuit.sectionId);
+      const deviceRows = circuit.deviceRows.map((row) => {
+        const normalizedPhaseType =
+          normalizeKnownElectricalPhaseType(row.phaseType);
+        const linkedPhaseType = row.linkedProjectDeviceId
+          ? projectDeviceById.get(row.linkedProjectDeviceId)?.phaseType
+          : undefined;
+        return {
+          ...row,
+          phaseType:
+            normalizedPhaseType ??
+            linkedPhaseType ??
+            (section?.key === "three_phase"
+              ? "three_phase"
+              : "single_phase"),
+        };
+      });
+      return {
+        ...circuit,
+        voltage: section
+          ? resolveProjectVoltage(
+              resolveCircuitPhaseType(
+                section.key,
+                deviceRows.map((row) => row.phaseType)
+              ),
+              snapshot.project
+            )
+          : circuit.voltage,
+        deviceRows,
+      };
+    }),
+  };
+}
+
+function upgradeLegacyProjectStateSnapshot(
+  snapshot: z.infer<typeof legacyProjectStateSnapshotSchema>
+): z.infer<typeof previousProjectStateSnapshotSchema> {
+  return {
+    ...snapshot,
+    schemaVersion: previousProjectStateSnapshotSchemaVersion,
+    project: {
+      ...snapshot.project,
+      internalProjectNumber: null,
+      externalProjectNumber: null,
+      buildingOwner: null,
+      description: null,
+    },
+  };
+}
+
+function upgradePreviousProjectStateSnapshot(
+  snapshot: z.infer<typeof previousProjectStateSnapshotSchema>
+): z.infer<typeof distributionBoardProjectStateSnapshotSchema> {
+  return {
+    ...snapshot,
+    schemaVersion: distributionBoardProjectStateSnapshotSchemaVersion,
+    distributionBoards: snapshot.distributionBoards.map((board) => ({
+      ...board,
+      floorId: null,
+      supplyType: null,
+    })),
+  };
+}
+
+function upgradeDistributionBoardProjectStateSnapshot(
+  snapshot: z.infer<typeof distributionBoardProjectStateSnapshotSchema>
+): z.infer<typeof supplyTypesProjectStateSnapshotSchema> {
+  return {
+    ...snapshot,
+    schemaVersion: supplyTypesProjectStateSnapshotSchemaVersion,
+    project: {
+      ...snapshot.project,
+      enabledDistributionBoardSupplyTypes: [
+        ...defaultDistributionBoardSupplyTypes,
+      ],
+    },
+  };
+}
+
+function upgradeSupplyTypesProjectStateSnapshot(
+  snapshot: z.infer<typeof supplyTypesProjectStateSnapshotSchema>
+): z.infer<typeof voltageProjectStateSnapshotSchema> {
+  const settings = snapshot.project;
+  const sectionById = new Map(
+    snapshot.circuitSections.map((section) => [section.id, section])
+  );
+  return {
+    ...snapshot,
+    schemaVersion: voltageProjectStateSnapshotSchemaVersion,
+    projectDevices: snapshot.projectDevices.map((device) => ({
+      ...device,
+      voltageV: resolveProjectVoltage(device.phaseType, settings),
+    })),
+    circuits: snapshot.circuits.map((circuit) => {
+      const section = sectionById.get(circuit.sectionId);
+      if (!section) {
+        return circuit;
+      }
+      const phaseType = resolveCircuitPhaseType(
+        section.key,
+        circuit.deviceRows.map((row) => row.phaseType)
+      );
+      return {
+        ...circuit,
+        voltage: resolveProjectVoltage(phaseType, settings),
+      };
+    }),
+  };
+}
+
+function upgradeVoltageProjectStateSnapshot(
+  snapshot: z.infer<typeof voltageProjectStateSnapshotSchema>
+): ProjectStateSnapshot {
+  return {
+    ...snapshot,
+    schemaVersion: projectStateSnapshotSchemaVersion,
+    distributionBoards: snapshot.distributionBoards.map((board) => ({
+      ...board,
+      simultaneityFactor: 1,
+    })),
+  };
+}
+
+function isPlainObject(value: unknown): value is Record<string, unknown> {
+  return value !== null && typeof value === "object" && !Array.isArray(value);
+}
+
 export function serializeProjectStateSnapshot(
   snapshot: ProjectStateSnapshot
 ): string {
@@ -199,6 +468,23 @@ function assertProjectStateSnapshotRelations(
 
   for (const board of snapshot.distributionBoards) {
     assertProjectOwnership(board.projectId, projectId, "distribution board");
+    if (board.floorId !== null) {
+      assertReference(
+        floorIds,
+        board.floorId,
+        "distribution board floor"
+      );
+    }
+    if (
+      board.supplyType !== null &&
+      !snapshot.project.enabledDistributionBoardSupplyTypes.includes(
+        board.supplyType
+      )
+    ) {
+      throw new Error(
+        "Snapshot distribution board uses a disabled supply type."
+      );
+    }
   }
   for (const list of snapshot.circuitLists) {
     assertProjectOwnership(list.projectId, projectId, "circuit list");
@@ -217,6 +503,14 @@ function assertProjectStateSnapshotRelations(
   }
   for (const device of snapshot.projectDevices) {
     assertProjectOwnership(device.projectId, projectId, "project device");
+    if (
+      device.voltageV !==
+      resolveProjectVoltage(device.phaseType, snapshot.project)
+    ) {
+      throw new Error(
+        "Snapshot project device voltage must match project settings."
+      );
+    }
   }
   for (const floor of snapshot.floors) {
     assertProjectOwnership(floor.projectId, projectId, "floor");
@@ -247,6 +541,18 @@ function assertProjectStateSnapshotRelations(
         "Snapshot circuit reserve state must match its device rows."
       );
     }
+    const expectedVoltage = resolveProjectVoltage(
+      resolveCircuitPhaseType(
+        section.key,
+        circuit.deviceRows.map((row) => row.phaseType)
+      ),
+      snapshot.project
+    );
+    if (circuit.voltage !== expectedVoltage) {
+      throw new Error(
+        "Snapshot circuit voltage must match project settings."
+      );
+    }
     for (const row of circuit.deviceRows) {
       if (row.circuitId !== circuit.id) {
         throw new Error(

src/domain/models/project-transfer.model.ts

@@ -0,0 +1,168 @@
+import {
+  parseProjectStateSnapshot,
+  projectStateSnapshotSchemaVersion,
+  type ProjectStateSnapshot,
+} from "./project-state-snapshot.model.js";
+
+export const projectTransferFormat = "leistungsbilanz.project" as const;
+export const projectTransferFormatVersion = 1 as const;
+
+export interface ProjectTransferEnvelope {
+  format: typeof projectTransferFormat;
+  formatVersion: typeof projectTransferFormatVersion;
+  exportedAtIso: string;
+  payloadSha256: string;
+  projectState: ProjectStateSnapshot;
+}
+
+export function createProjectTransferEnvelope(
+  exportedAtIso: string,
+  payloadSha256: string,
+  projectState: ProjectStateSnapshot
+): ProjectTransferEnvelope {
+  return parseProjectTransferEnvelope({
+    format: projectTransferFormat,
+    formatVersion: projectTransferFormatVersion,
+    exportedAtIso,
+    payloadSha256,
+    projectState,
+  });
+}
+
+export function parseProjectTransferEnvelope(
+  value: unknown
+): ProjectTransferEnvelope {
+  if (!isPlainObject(value)) {
+    throw new Error("Project transfer file must be an object.");
+  }
+  if (
+    value.format !== projectTransferFormat ||
+    value.formatVersion !== projectTransferFormatVersion
+  ) {
+    throw new Error("Project transfer format is not supported.");
+  }
+  if (
+    typeof value.exportedAtIso !== "string" ||
+    !Number.isFinite(Date.parse(value.exportedAtIso))
+  ) {
+    throw new Error("Project transfer timestamp is invalid.");
+  }
+  if (
+    typeof value.payloadSha256 !== "string" ||
+    !/^[a-f0-9]{64}$/.test(value.payloadSha256)
+  ) {
+    throw new Error("Project transfer checksum is invalid.");
+  }
+  const projectState = parseProjectStateSnapshot(value.projectState);
+  if (projectState.schemaVersion !== projectStateSnapshotSchemaVersion) {
+    throw new Error("Project transfer snapshot version is not supported.");
+  }
+  if (Object.keys(value).length !== 5) {
+    throw new Error("Project transfer file contains unknown fields.");
+  }
+  return {
+    format: projectTransferFormat,
+    formatVersion: projectTransferFormatVersion,
+    exportedAtIso: value.exportedAtIso,
+    payloadSha256: value.payloadSha256,
+    projectState,
+  };
+}
+
+export function remapProjectState(
+  source: ProjectStateSnapshot,
+  targetProjectId: string,
+  createId: () => string,
+  name: string = source.project.name
+): ProjectStateSnapshot {
+  const boardIds = idMap(source.distributionBoards, createId);
+  const listIds = idMap(source.circuitLists, createId);
+  const sectionIds = idMap(source.circuitSections, createId);
+  const circuitIds = idMap(source.circuits, createId);
+  const deviceIds = idMap(source.projectDevices, createId);
+  const floorIds = idMap(source.floors, createId);
+  const roomIds = idMap(source.rooms, createId);
+  const rowIds = new Map(
+    source.circuits.flatMap((circuit) =>
+      circuit.deviceRows.map((row) => [row.id, createId()] as const)
+    )
+  );
+  return parseProjectStateSnapshot({
+    ...source,
+    project: { ...source.project, id: targetProjectId, name },
+    distributionBoards: source.distributionBoards.map((board) => ({
+      ...board,
+      id: requiredId(boardIds, board.id),
+      projectId: targetProjectId,
+      floorId:
+        board.floorId === null
+          ? null
+          : requiredId(floorIds, board.floorId),
+    })),
+    circuitLists: source.circuitLists.map((list) => ({
+      ...list,
+      id: requiredId(listIds, list.id),
+      projectId: targetProjectId,
+      distributionBoardId: requiredId(boardIds, list.distributionBoardId),
+    })),
+    circuitSections: source.circuitSections.map((section) => ({
+      ...section,
+      id: requiredId(sectionIds, section.id),
+      circuitListId: requiredId(listIds, section.circuitListId),
+    })),
+    circuits: source.circuits.map((circuit) => ({
+      ...circuit,
+      id: requiredId(circuitIds, circuit.id),
+      circuitListId: requiredId(listIds, circuit.circuitListId),
+      sectionId: requiredId(sectionIds, circuit.sectionId),
+      deviceRows: circuit.deviceRows.map((row) => ({
+        ...row,
+        id: requiredId(rowIds, row.id),
+        circuitId: requiredId(circuitIds, circuit.id),
+        linkedProjectDeviceId:
+          row.linkedProjectDeviceId === null
+            ? null
+            : requiredId(deviceIds, row.linkedProjectDeviceId),
+        legacyConsumerId: null,
+        roomId:
+          row.roomId === null ? null : requiredId(roomIds, row.roomId),
+      })),
+    })),
+    projectDevices: source.projectDevices.map((device) => ({
+      ...device,
+      id: requiredId(deviceIds, device.id),
+      projectId: targetProjectId,
+    })),
+    floors: source.floors.map((floor) => ({
+      ...floor,
+      id: requiredId(floorIds, floor.id),
+      projectId: targetProjectId,
+    })),
+    rooms: source.rooms.map((room) => ({
+      ...room,
+      id: requiredId(roomIds, room.id),
+      projectId: targetProjectId,
+      floorId:
+        room.floorId === null ? null : requiredId(floorIds, room.floorId),
+    })),
+  });
+}
+
+function idMap(
+  entries: ReadonlyArray<{ id: string }>,
+  createId: () => string
+) {
+  return new Map(entries.map((entry) => [entry.id, createId()]));
+}
+
+function requiredId(ids: ReadonlyMap<string, string>, sourceId: string) {
+  const targetId = ids.get(sourceId);
+  if (!targetId) {
+    throw new Error(`Project transfer reference "${sourceId}" is invalid.`);
+  }
+  return targetId;
+}
+
+function isPlainObject(value: unknown): value is Record<string, unknown> {
+  return value !== null && typeof value === "object" && !Array.isArray(value);
+}

src/domain/ports/distribution-board-structure-project-command.store.ts

@@ -1,4 +1,5 @@
 import type { DistributionBoardStructureProjectCommand } from "../models/distribution-board-structure-project-command.model.js";
+import type { DistributionBoardUpdateProjectCommand } from "../models/distribution-board-project-command.model.js";
 import type {
   AppendedProjectRevision,
   ProjectRevisionSource,
@@ -23,4 +24,15 @@ export interface DistributionBoardStructureProjectCommandStore {
   execute(
     input: ExecuteDistributionBoardStructureCommandInput
   ): ExecutedDistributionBoardStructureCommand;
+  executeUpdate(
+    input: Omit<
+      ExecuteDistributionBoardStructureCommandInput,
+      "command"
+    > & {
+      command: DistributionBoardUpdateProjectCommand;
+    }
+  ): {
+    revision: AppendedProjectRevision;
+    inverse: DistributionBoardUpdateProjectCommand;
+  };
 }

src/domain/ports/project-history.store.ts

@@ -47,6 +47,10 @@ export interface ProjectHistoryStore {
   listRevisions(
     input: ListProjectRevisionsInput
   ): ProjectRevisionPage | null;
+  listRevisionsByNumbers(
+    projectId: string,
+    revisionNumbers: number[]
+  ): ProjectRevisionSummary[];
   getNextCommand(
     projectId: string,
     direction: ProjectHistoryDirection

src/domain/ports/project-transfer.store.ts

@@ -0,0 +1,15 @@
+import type { ProjectStateRestoreCommand } from "../models/project-state-restore-command.model.js";
+import type { ProjectTransferEnvelope } from "../models/project-transfer.model.js";
+
+export interface PreparedProjectTransferReplace {
+  command: ProjectStateRestoreCommand;
+}
+
+export interface ProjectTransferStore {
+  exportProject(projectId: string): ProjectTransferEnvelope | null;
+  prepareReplace(
+    projectId: string,
+    transfer: unknown
+  ): PreparedProjectTransferReplace | null;
+  importDuplicate(transfer: unknown): { projectId: string; name: string };
+}

src/domain/services/project-command.service.ts

@@ -37,6 +37,10 @@ import {
   circuitDeleteCommandType,
   circuitInsertCommandType,
 } from "../models/circuit-structure-project-command.model.js";
+import {
+  assertDistributionBoardUpdateProjectCommand,
+  distributionBoardUpdateCommandType,
+} from "../models/distribution-board-project-command.model.js";
 import {
   assertDistributionBoardDeleteProjectCommand,
   assertDistributionBoardInsertProjectCommand,
@@ -285,6 +289,13 @@ export class ProjectCommandService implements ProjectCommandExecutor {
           command: input.command,
         }).revision;
       }
+      case distributionBoardUpdateCommandType: {
+        assertDistributionBoardUpdateProjectCommand(input.command);
+        return this.distributionBoardStructureStore.executeUpdate({
+          ...input,
+          command: input.command,
+        }).revision;
+      }
       case projectFloorInsertCommandType: {
         assertProjectFloorInsertProjectCommand(input.command);
         return this.projectLocationStructureStore.execute({

src/domain/services/project-voltage.service.ts

@@ -0,0 +1,68 @@
+export type ElectricalPhaseType = "single_phase" | "three_phase";
+
+export function isElectricalPhaseType(
+  value: unknown
+): value is ElectricalPhaseType {
+  return value === "single_phase" || value === "three_phase";
+}
+
+export function normalizeKnownElectricalPhaseType(
+  value: string | null
+): ElectricalPhaseType | null {
+  if (value === null) {
+    return null;
+  }
+  const normalized = value
+    .trim()
+    .toLocaleLowerCase("de-DE")
+    .replaceAll("-", "")
+    .replaceAll("_", "");
+  if (
+    ["1ph", "1phase", "1phasig", "einphasig", "singlephase"].includes(
+      normalized
+    )
+  ) {
+    return "single_phase";
+  }
+  if (
+    ["3ph", "3phase", "3phasig", "dreiphasig", "threephase"].includes(
+      normalized
+    )
+  ) {
+    return "three_phase";
+  }
+  throw new Error(`Unknown electrical phase type: ${value}`);
+}
+
+export interface ProjectVoltageSettings {
+  singlePhaseVoltageV: number;
+  threePhaseVoltageV: number;
+}
+
+export function resolveProjectVoltage(
+  phaseType: ElectricalPhaseType,
+  settings: ProjectVoltageSettings
+) {
+  return phaseType === "three_phase"
+    ? settings.threePhaseVoltageV
+    : settings.singlePhaseVoltageV;
+}
+
+export function resolveCircuitPhaseType(
+  sectionKey: string,
+  devicePhaseTypes: ReadonlyArray<string | null | undefined> = []
+): ElectricalPhaseType {
+  if (sectionKey === "three_phase") {
+    return "three_phase";
+  }
+  if (sectionKey === "lighting" || sectionKey === "single_phase") {
+    return "single_phase";
+  }
+  const assignedPhaseTypes = devicePhaseTypes.filter(
+    isElectricalPhaseType
+  );
+  return assignedPhaseTypes.length > 0 &&
+    assignedPhaseTypes.every((phaseType) => phaseType === "three_phase")
+    ? "three_phase"
+    : "single_phase";
+}

src/frontend/components/circuit-tree-editor.tsx

@@ -5,6 +5,10 @@ import {
   inferProjectDeviceSectionKey,
   isProjectDevicePlacementValid,
 } from "../../domain/services/project-device-placement.service";
+import {
+  resolveCircuitPhaseType,
+  resolveProjectVoltage,
+} from "../../domain/services/project-voltage.service";
 import {
   getInsertionSortOrder,
   resolveGridInsertionIntent,
@@ -21,7 +25,13 @@ import {
   buildDeviceRowEditPatch,
   defaultVisibleColumnKeys,
   deviceFieldKeys,
+  formatPhaseTypeLabel,
   formatValue,
+  getCircuitSectionLabel,
+  getProjectColumnLayoutStorageKey,
+  isGridEditorControlTarget,
+  normalizeColumnOrder,
+  parseStoredColumnLayout,
 } from "../utils/circuit-grid-model";
 import {
   buildCircuitDeviceRowInsertSnapshot,
@@ -125,7 +135,8 @@ type CircuitReorderDropIntent =
   | { kind: "after-circuit"; sectionId: string; targetCircuitId: string; valid: boolean }
   | { kind: "section-end"; sectionId: string; valid: boolean };
 
-const COLUMN_LAYOUT_STORAGE_KEY = "circuitTreeEditor.columnLayout.v1";
+const LEGACY_COLUMN_LAYOUT_STORAGE_KEY =
+  "circuitTreeEditor.columnLayout.v1";
 
 function normalizeUiError(err: unknown): string {
   const message = err instanceof Error ? err.message : "Der Vorgang ist fehlgeschlagen.";
@@ -149,14 +160,8 @@ function normalizeUiError(err: unknown): string {
   return message;
 }
 
-function formatPhaseTypeLabel(value: string): string {
+function getFullColumnLabel(column: ColumnDef): string {
-  if (value === "three_phase") {
+  return column.fullLabel ?? column.label;
-    return "Dreiphasig";
-  }
-  if (value === "single_phase") {
-    return "Einphasig";
-  }
-  return value;
 }
 
 function isPrintableKey(event: KeyboardEvent<HTMLElement>) {
@@ -196,6 +201,8 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
   const [activeSectionId, setActiveSectionId] = useState<string | null>(null);
   const [isSaving, setIsSaving] = useState(false);
   const [projectDevices, setProjectDevices] = useState<ProjectDeviceDto[]>([]);
+  const [isProjectDeviceDrawerOpen, setIsProjectDeviceDrawerOpen] =
+    useState(false);
   const [projectDeviceSearch, setProjectDeviceSearch] = useState("");
   const [selectedProjectDeviceId, setSelectedProjectDeviceId] = useState<string | null>(null);
   const [targetSectionId, setTargetSectionId] = useState<string | null>(null);
@@ -220,6 +227,10 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
   const [filterValueSearch, setFilterValueSearch] = useState("");
   const [visibleColumnKeys, setVisibleColumnKeys] = useState<CellKey[]>(defaultVisibleColumnKeys);
   const [columnOrder, setColumnOrder] = useState<CellKey[]>(allColumns.map((column) => column.key));
+  const [
+    loadedColumnLayoutProjectId,
+    setLoadedColumnLayoutProjectId,
+  ] = useState<string | null>(null);
   const [isColumnMenuOpen, setIsColumnMenuOpen] = useState(false);
   const [columnSearch, setColumnSearch] = useState("");
   const [draggingColumnKey, setDraggingColumnKey] = useState<CellKey | null>(null);
@@ -229,7 +240,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
   const pendingSelectedDeviceRowIdsAfterReload = useRef<string[] | null>(null);
   const pendingSelectedCircuitIdsAfterReload = useRef<string[] | null>(null);
   const containerRef = useRef<HTMLDivElement | null>(null);
-  const inputRef = useRef<HTMLInputElement | null>(null);
+  const inputRef = useRef<HTMLInputElement | HTMLSelectElement | null>(null);
   const focusTokenRef = useRef(1);
   const projectRevisionRef = useRef<number | null>(null);
 
@@ -265,13 +276,6 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     }
   }
 
-  function normalizeColumnOrder(keys: CellKey[]) {
-    const unique = [...new Set(keys)];
-    const allKeys = allColumns.map((column) => column.key);
-    const merged = [...unique, ...allKeys.filter((key) => !unique.includes(key))];
-    return ["equipmentIdentifier" as CellKey, ...merged.filter((key) => key !== "equipmentIdentifier")];
-  }
-
   // Initial/identity-change tree load for current route context.
   useEffect(() => {
     void loadTree({ showLoading: true });
@@ -290,32 +294,48 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
   }, [projectId]);
 
   useEffect(() => {
+    setLoadedColumnLayoutProjectId(null);
+    setColumnOrder(allColumns.map((column) => column.key));
+    setVisibleColumnKeys(defaultVisibleColumnKeys);
     try {
-      const raw = localStorage.getItem(COLUMN_LAYOUT_STORAGE_KEY);
+      const parsed = parseStoredColumnLayout(
-      if (!raw) {
+        localStorage.getItem(
+          getProjectColumnLayoutStorageKey(projectId)
+        ) ??
+          localStorage.getItem(
+            LEGACY_COLUMN_LAYOUT_STORAGE_KEY
+          )
+      );
+      if (!parsed) {
         return;
       }
-      const parsed = JSON.parse(raw) as { order?: string[]; visible?: string[] };
+      setColumnOrder(parsed.order);
-      const validKeys = new Set(allColumns.map((column) => column.key));
+      setVisibleColumnKeys(parsed.visible);
-      const parsedOrder = (parsed.order ?? []).filter((key): key is CellKey => validKeys.has(key as CellKey));
-      const parsedVisible = (parsed.visible ?? []).filter((key): key is CellKey => validKeys.has(key as CellKey));
-      if (!parsedOrder.length || !parsedVisible.length || !parsedVisible.includes("equipmentIdentifier")) {
-        return;
-      }
-      setColumnOrder(normalizeColumnOrder(parsedOrder));
-      setVisibleColumnKeys(parsedVisible);
     } catch {
       // ignore invalid local storage and use defaults
+    } finally {
+      setLoadedColumnLayoutProjectId(projectId);
     }
-  }, []);
+  }, [projectId]);
 
   useEffect(() => {
+    if (loadedColumnLayoutProjectId !== projectId) {
+      return;
+    }
     const payload = {
       order: columnOrder,
       visible: visibleColumnKeys,
     };
-    localStorage.setItem(COLUMN_LAYOUT_STORAGE_KEY, JSON.stringify(payload));
+    localStorage.setItem(
-  }, [columnOrder, visibleColumnKeys]);
+      getProjectColumnLayoutStorageKey(projectId),
+      JSON.stringify(payload)
+    );
+  }, [
+    columnOrder,
+    loadedColumnLayoutProjectId,
+    projectId,
+    visibleColumnKeys,
+  ]);
 
   useEffect(() => {
     const visible = new Set(visibleColumnKeys);
@@ -443,7 +463,14 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
           </button>
         ) : null}
         {activeColumnFilters.map(({ column, values }) => {
-          const shownValues = values.slice(0, 2).join(", ");
+          const shownValues = values
+            .slice(0, 2)
+            .map((value) =>
+              column.key === "phaseType"
+                ? formatPhaseTypeLabel(value)
+                : value
+            )
+            .join(", ");
           const valueSummary = values.length > 2 ? `${shownValues} +${values.length - 2}` : shownValues;
           return (
             <button
@@ -465,6 +492,51 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     );
   }
 
+  function renderDistributionPowerSummary() {
+    if (!data) {
+      return null;
+    }
+    return (
+      <section
+        className="distribution-power-summary"
+        aria-label="Leistungszusammenfassung des Verteilers"
+      >
+        <div>
+          <span>Gesamtleistung Verteiler</span>
+          <strong>
+            {formatValue(
+              data.distributionBoardTotalPower,
+              "rowTotalPower"
+            )}{" "}
+            kW
+          </strong>
+        </div>
+        <div>
+          <span>Verteilerweiter Gleichzeitigkeitsfaktor</span>
+          <strong>
+            {formatValue(
+              data.distributionBoardSimultaneityFactor,
+              "simultaneityFactor"
+            )}
+          </strong>
+        </div>
+        <div>
+          <span>
+            Gesamtleistung Verteiler unter Berücksichtigung des
+            Gleichzeitigkeitsfaktors
+          </span>
+          <strong>
+            {formatValue(
+              data.distributionBoardTotalPowerWithSimultaneityFactor,
+              "rowTotalPower"
+            )}{" "}
+            kW
+          </strong>
+        </div>
+      </section>
+    );
+  }
+
   function closeColumnSettingsMenu() {
     setIsColumnMenuOpen(false);
     setColumnSearch("");
@@ -486,7 +558,9 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
 
     const search = columnSearch.trim().toLocaleLowerCase("de-DE");
     const matchingColumns = orderedColumns.filter((column) =>
-      column.label.toLocaleLowerCase("de-DE").includes(search)
+      `${column.label} ${getFullColumnLabel(column)}`
+        .toLocaleLowerCase("de-DE")
+        .includes(search)
     );
 
     return (
@@ -530,7 +604,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                   onClick={() => toggleColumnVisibility(column.key)}
                 >
                   <span className="selection-marker" aria-hidden="true">{visible ? "✓" : ""}</span>
-                  <span>{column.label}</span>
+                  <span>{getFullColumnLabel(column)}</span>
                 </button>
                 <div className="column-settings-order">
                   <button type="button" onClick={() => moveColumn(column.key, -1)} disabled={column.locked} title="Spalte nach links verschieben">
@@ -817,6 +891,19 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     values: CreateCircuitInputDto,
     deviceRowValues: CreateCircuitDeviceRowInputDto[] = []
   ) {
+    const section = data?.sections.find(
+      (entry) => entry.id === values.sectionId
+    );
+    if (!section || !data) {
+      throw new Error("Bereich wurde nicht gefunden.");
+    }
+    const voltage = resolveProjectVoltage(
+      resolveCircuitPhaseType(
+        section.key,
+        deviceRowValues.map((row) => row.phaseType)
+      ),
+      data
+    );
     const circuitId = crypto.randomUUID();
     const deviceRows = deviceRowValues.map((row, index) =>
       createDeviceRowSnapshot(circuitId, row, (index + 1) * 10)
@@ -824,7 +911,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     return buildCircuitInsertSnapshot({
       id: circuitId,
       circuitListId,
-      values,
+      values: { ...values, voltage },
       deviceRows,
     });
   }
@@ -1194,9 +1281,12 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
         return;
       }
       inputRef.current.focus();
-      if (editingCell.mode === "selectExisting") {
+      if (
+        inputRef.current instanceof HTMLInputElement &&
+        editingCell.mode === "selectExisting"
+      ) {
         inputRef.current.select();
-      } else {
+      } else if (inputRef.current instanceof HTMLInputElement) {
         const len = inputRef.current.value.length;
         inputRef.current.setSelectionRange(len, len);
       }
@@ -1226,7 +1316,10 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
       return;
     }
     // Spreadsheet behavior: typing on a selected cell starts overwrite mode.
-    const currentDisplay = mode === "replaceWithTypedChar" ? typedChar ?? "" : String(visibleCell.value ?? "");
+    const currentDisplay =
+      mode === "replaceWithTypedChar" && cell.cellKey !== "phaseType"
+        ? typedChar ?? ""
+        : String(visibleCell.value ?? "");
     focusTokenRef.current += 1;
     setEditingCell({
       ...cell,
@@ -1365,7 +1458,10 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
   }
 
   // Commits the active editor input through command history so edits remain undoable.
-  async function commitEdit(direction: SaveDirection = "stay") {
+  async function commitEdit(
+    direction: SaveDirection = "stay",
+    draftOverride?: string
+  ) {
     if (!editingCell) {
       return;
     }
@@ -1375,10 +1471,11 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
       setEditingCell(null);
       return;
     }
+    const draft = draftOverride ?? editingCell.draft;
     if (
       editingCell.cellKey === "equipmentIdentifier" &&
       row.circuit &&
-      hasEquipmentIdentifierConflict(allCircuits, row.circuit.id, editingCell.draft)
+      hasEquipmentIdentifierConflict(allCircuits, row.circuit.id, draft)
     ) {
       setError("Dieses Betriebsmittelkennzeichen ist bereits vorhanden. Die Änderung wurde nicht gespeichert.");
       return;
@@ -1405,7 +1502,11 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
       const command: HistoryCommand = {
         label: "Aus freier Zeile erstellen",
         redo: async () => {
-          const selection = await createFromPlaceholder(row.sectionId, editingCell.cellKey, editingCell.draft);
+          const selection = await createFromPlaceholder(
+            row.sectionId,
+            editingCell.cellKey,
+            draft
+          );
           targetSelection = selection;
           return nextSelectionIntent();
         },
@@ -1416,7 +1517,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     }
 
     if (cell.kind === "circuitField" && row.circuit) {
-      const next = editingCell.draft;
+      const next = draft;
       const command: HistoryCommand = {
         label: "Stromkreisfeld bearbeiten",
         redo: async () => {
@@ -1430,7 +1531,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     }
 
     if (cell.kind === "deviceField" && row.device) {
-      const next = editingCell.draft;
+      const next = draft;
       const command: HistoryCommand = {
         label: "Gerätefeld bearbeiten",
         redo: async () => {
@@ -1444,7 +1545,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     }
 
     if (cell.kind === "deviceField" && row.rowType === "reserveCircuit" && row.circuit) {
-      const next = editingCell.draft;
+      const next = draft;
       const command: HistoryCommand = {
         label: "Gerätezeile im Reservestromkreis erstellen",
         redo: async () => {
@@ -2452,6 +2553,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
         {renderColumnSettingsMenu("col-empty")}
       </div>
         {renderActiveViewSummary()}
+        {renderDistributionPowerSummary()}
         {error ? (
           <div className="notice error editor-error-notice" role="alert">
             <span>{error}</span>
@@ -2537,6 +2639,19 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
         <button type="button" onClick={toggleColumnSettingsMenu} aria-expanded={isColumnMenuOpen}>
           Spalten
         </button>
+        <button
+          aria-controls="project-device-drawer"
+          aria-expanded={isProjectDeviceDrawerOpen}
+          className="project-device-drawer-toggle"
+          type="button"
+          onClick={() =>
+            setIsProjectDeviceDrawerOpen((current) => !current)
+          }
+        >
+          {isProjectDeviceDrawerOpen
+            ? "Projektgeräte schließen"
+            : `Projektgeräte öffnen (${projectDevices.length})`}
+        </button>
         <button
           type="button"
           onClick={clearSortAndFilters}
@@ -2547,6 +2662,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
         {renderColumnSettingsMenu("col")}
       </div>
       {renderActiveViewSummary()}
+      {renderDistributionPowerSummary()}
       {hasActiveSortOrFilter ? (
         <div className="notice muted">Sortierung und Filter verändern nur die Ansicht. Die Neunummerierung ist währenddessen deaktiviert.</div>
       ) : null}
@@ -2566,8 +2682,25 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
       ) : null}
       {isSaving ? <div className="notice info">Wird gespeichert …</div> : null}
       <div className="tree-editor-layout">
-        <aside className="project-device-sidebar">
+        {isProjectDeviceDrawerOpen ? (
+        <aside
+          className="project-device-sidebar project-device-drawer"
+          id="project-device-drawer"
+        >
+          <div className="project-device-drawer-header">
+            <div>
               <h3>Projektgeräte</h3>
+              <span>{projectDevices.length} verfügbar</span>
+            </div>
+            <button
+              aria-label="Projektgeräte schließen"
+              disabled={draggingProjectDeviceId !== null}
+              onClick={() => setIsProjectDeviceDrawerOpen(false)}
+              type="button"
+            >
+              Schließen
+            </button>
+          </div>
           <input
             type="text"
             placeholder="Name oder Anzeigename suchen …"
@@ -2604,10 +2737,17 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                 <strong>{device.displayName || device.name}</strong>
                 <span>Name: {device.name}</span>
                 <span>Phasenart: {formatPhaseTypeLabel(device.phaseType)}</span>
-                <span>Anzahl: {device.quantity}</span>
+                <span>Anzahl: {formatValue(device.quantity, "quantity")}</span>
-                <span>Leistung/Gerät: {device.powerPerUnit}</span>
+                <span>
-                <span>Gleichzeitigkeit: {device.simultaneityFactor}</span>
+                  Leistung/Gerät: {formatValue(device.powerPerUnit, "powerPerUnit")} kW
-                <span>Gesamtleistung: {device.totalPower}</span>
+                </span>
+                <span>
+                  Gleichzeitigkeit:{" "}
+                  {formatValue(device.simultaneityFactor, "simultaneityFactor")}
+                </span>
+                <span>
+                  Gesamtleistung: {formatValue(device.totalPower, "rowTotalPower")} kW
+                </span>
                 <span>Kostengruppe: {device.costGroup || "-"}</span>
                 <span>Kategorie: {device.category || "-"}</span>
               </button>
@@ -2626,14 +2766,18 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                   const valid = !selectedProjectDevice || isProjectDevicePlacementValid(selectedProjectDevice, section);
                   return (
                     <option key={section.id} value={section.id} disabled={!valid}>
-                      {section.displayName}{valid ? "" : " (nicht zulässig)"}
+                      {getCircuitSectionLabel(section)}
+                      {valid ? "" : " (nicht zulässig)"}
                     </option>
                   );
                 })}
               </select>
             </label>
             {selectedProjectDevice && suggestedSection ? (
-              <p className="notice muted">Vorgeschlagener Bereich: {suggestedSection.displayName}</p>
+              <p className="notice muted">
+                Vorgeschlagener Bereich:{" "}
+                {getCircuitSectionLabel(suggestedSection)}
+              </p>
             ) : null}
             <button
               type="button"
@@ -2668,6 +2812,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
             </button>
           </div>
         </aside>
+        ) : null}
         <div
           className="tree-grid-wrap"
           ref={containerRef}
@@ -2690,8 +2835,8 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                     <button
                       type="button"
                       className="header-sort-btn"
-                      aria-label={`${column.label} sortieren`}
+                      aria-label={`${getFullColumnLabel(column)} sortieren`}
-                      title="Zum Sortieren klicken"
+                      title={`${getFullColumnLabel(column)} – zum Sortieren klicken`}
                       onClick={() => {
                         setSortState((current) => {
                           if (!current || current.key !== column.key) {
@@ -2719,7 +2864,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                       title={
                         (columnFilters[column.key]?.length ?? 0) > 0
                           ? `${columnFilters[column.key]?.length} Filterwert(e) ausgewählt`
-                          : `${column.label} filtern`
+                          : `${getFullColumnLabel(column)} filtern`
                       }
                     >
                       Filtern{(columnFilters[column.key]?.length ?? 0) > 0 ? ` (${columnFilters[column.key]?.length})` : ""}
@@ -2728,7 +2873,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                   {openFilterColumn === column.key ? (
                     <div className="header-filter-menu">
                       <div className="header-filter-title-row">
-                        <strong>{column.label} filtern</strong>
+                        <strong>{getFullColumnLabel(column)} filtern</strong>
                         <button type="button" className="header-filter-close" onClick={closeColumnFilterMenu} aria-label="Filter schließen">
                           ×
                         </button>
@@ -2742,7 +2887,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                         value={filterValueSearch}
                         onChange={(event) => setFilterValueSearch(event.target.value)}
                         placeholder="Werte suchen …"
-                        aria-label={`Werte für ${column.label} suchen`}
+                        aria-label={`Werte für ${getFullColumnLabel(column)} suchen`}
                         autoFocus
                       />
                       <div className="header-filter-selection-actions">
@@ -2759,7 +2904,18 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                       </div>
                       <div className="header-filter-values">
                         {(distinctValuesByColumn[column.key] ?? [])
-                          .filter((value) => value.toLocaleLowerCase("de-DE").includes(filterValueSearch.trim().toLocaleLowerCase("de-DE")))
+                          .filter((value) =>
+                            (column.key === "phaseType"
+                              ? formatPhaseTypeLabel(value)
+                              : value
+                            )
+                              .toLocaleLowerCase("de-DE")
+                              .includes(
+                                filterValueSearch
+                                  .trim()
+                                  .toLocaleLowerCase("de-DE")
+                              )
+                          )
                           .map((value) => {
                             const selected = filterDraftValues.includes(value);
                             return (
@@ -2777,12 +2933,26 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                                 }
                               >
                                 <span className="selection-marker" aria-hidden="true">{selected ? "✓" : ""}</span>
-                                <span>{value}</span>
+                                <span>
+                                  {column.key === "phaseType"
+                                    ? formatPhaseTypeLabel(value)
+                                    : value}
+                                </span>
                               </button>
                             );
                         })}
-                        {(distinctValuesByColumn[column.key] ?? []).filter((value) =>
+                        {(distinctValuesByColumn[column.key] ?? []).filter(
-                          value.toLocaleLowerCase("de-DE").includes(filterValueSearch.trim().toLocaleLowerCase("de-DE"))
+                          (value) =>
+                            (column.key === "phaseType"
+                              ? formatPhaseTypeLabel(value)
+                              : value
+                            )
+                              .toLocaleLowerCase("de-DE")
+                              .includes(
+                                filterValueSearch
+                                  .trim()
+                                  .toLocaleLowerCase("de-DE")
+                              )
                         ).length === 0 ? (
                           <div className="header-filter-empty">Keine passenden Werte gefunden.</div>
                         ) : null}
@@ -2879,7 +3049,19 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                   >
                     <td colSpan={visibleColumns.length + 1} className="section-drop-cell">
                       <div className="section-content">
-                        <strong>{section.displayName}</strong>
+                        <div className="section-title">
+                          <strong>
+                            {getCircuitSectionLabel(section)}
+                          </strong>
+                          <span>
+                            Gesamtleistung Abschnitt:{" "}
+                            {formatValue(
+                              section.sectionTotalPower,
+                              "rowTotalPower"
+                            )}{" "}
+                            kW
+                          </span>
+                        </div>
                         <div className="section-actions">
                           <button type="button" tabIndex={-1} onClick={() => void handleAddReserveCircuit(section.id)}>
                             Stromkreis hinzufügen
@@ -3304,6 +3486,9 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                           setCircuitReorderIntent(null);
                         }}
                         onClick={(event) => {
+                          if (isGridEditorControlTarget(event.target)) {
+                            return;
+                          }
                           if (cell.editable) {
                             handleRowSelectionClick(row, column.key, {
                               ctrlKey: event.ctrlKey,
@@ -3312,15 +3497,61 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                             });
                           }
                         }}
-                        onDoubleClick={() => {
+                        onDoubleClick={(event) => {
+                          if (isGridEditorControlTarget(event.target)) {
+                            return;
+                          }
                           if (cell.editable) {
                             startEdit({ rowKey: row.rowKey, cellKey: column.key }, "selectExisting");
                           }
                         }}
                       >
-                        {isEditing ? (
+                        {isEditing && column.key === "phaseType" ? (
+                          <select
+                            ref={(element) => {
+                              inputRef.current = element;
+                            }}
+                            value={editingCell.draft}
+                            aria-label="Phasenart auswählen"
+                            onChange={(event) =>
+                              void commitEdit("stay", event.target.value)
+                            }
+                            onKeyDown={(event) => {
+                              if (event.key === "Enter") {
+                                event.preventDefault();
+                                void commitEdit("stay");
+                              } else if (event.key === "Escape") {
+                                event.preventDefault();
+                                cancelEdit();
+                              } else if (event.key === "Tab") {
+                                event.preventDefault();
+                                void commitEdit(
+                                  event.shiftKey ? "prev" : "next"
+                                );
+                              }
+                            }}
+                            onBlur={() => {
+                              requestAnimationFrame(() => {
+                                const active =
+                                  document.activeElement as HTMLElement | null;
+                                if (
+                                  !active ||
+                                  !containerRef.current?.contains(active)
+                                ) {
+                                  setEditingCell(null);
+                                  focusGridWithoutScroll();
+                                }
+                              });
+                            }}
+                          >
+                            <option value="single_phase">1-phasig</option>
+                            <option value="three_phase">3-phasig</option>
+                          </select>
+                        ) : isEditing ? (
                           <input
-                            ref={inputRef}
+                            ref={(element) => {
+                              inputRef.current = element;
+                            }}
                             value={editingCell.draft}
                             aria-invalid={hasDraftIdentifierConflict}
                             title={hasDraftIdentifierConflict ? "Dieses Betriebsmittelkennzeichen ist bereits vorhanden." : undefined}
@@ -3352,7 +3583,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                             }}
                           />
                         ) : (
-                          formatValue(cell.value)
+                          formatValue(cell.value, column.key)
                         )}
                       </td>
                     );

src/frontend/components/circuit-tree-preview.tsx

@@ -4,26 +4,10 @@ import { useEffect, useState } from "react";
 import { Fragment } from "react";
 import { getCircuitTree } from "../utils/api";
 import type { CircuitTreeCircuitDto, CircuitTreeResponseDto } from "../types";
-
+import {
-function formatNumber(value: number | undefined, digits = 2) {
+  formatValue,
-  if (value === undefined || Number.isNaN(value)) {
+  getCircuitSectionLabel,
-    return "-";
+} from "../utils/circuit-grid-model";
-  }
-  return new Intl.NumberFormat("de-DE", {
-    minimumFractionDigits: digits,
-    maximumFractionDigits: digits,
-  }).format(value);
-}
-
-function formatPhaseType(value: string | undefined) {
-  if (value === "three_phase") {
-    return "Dreiphasig";
-  }
-  if (value === "single_phase") {
-    return "Einphasig";
-  }
-  return value ?? "-";
-}
 
 function renderCircuitSummaryLabel(circuit: CircuitTreeCircuitDto) {
   if (circuit.displayName?.trim()) {
@@ -86,11 +70,10 @@ export function CircuitTreePreview(props: { projectId: string; circuitListId: st
                 <th>Raumnummer</th>
                 <th>Raumname</th>
                 <th className="text-end">Anzahl</th>
-                <th className="text-end">Leistung / Gerät</th>
+                <th className="text-end">Leistung / Gerät [kW]</th>
                 <th className="text-end">Gleichzeitigkeit</th>
                 <th className="text-end">cos φ</th>
-                <th className="text-end">Zeilensumme</th>
+                <th className="text-end">Gesamtsumme [kW]</th>
-                <th className="text-end">Stromkreissumme</th>
                 <th>Schutzart</th>
                 <th className="text-end">Bemessungsstrom</th>
                 <th>Charakteristik</th>
@@ -117,8 +100,8 @@ function SectionRows(props: { section: CircuitTreeResponseDto["sections"][number
   return (
     <>
       <tr className="section-row">
-        <td colSpan={22}>
+        <td colSpan={21}>
-          <strong>{section.displayName}</strong>
+          <strong>{getCircuitSectionLabel(section)}</strong>
         </td>
       </tr>
       {section.circuits.map((circuit) => {
@@ -127,14 +110,18 @@ function SectionRows(props: { section: CircuitTreeResponseDto["sections"][number
             <tr key={circuit.id} className="reserve-row">
               <td>{circuit.equipmentIdentifier}</td>
               <td>{circuit.displayName?.trim() || "Reserve"}</td>
-              <td colSpan={12}>-</td>
+              <td colSpan={11}>-</td>
-              <td className="text-end">{formatNumber(circuit.circuitTotalPower)}</td>
+              <td className="text-end">
+                {formatValue(circuit.circuitTotalPower, "circuitTotalPower")}
+              </td>
               <td>{circuit.protectionType ?? "-"}</td>
-              <td className="text-end">{formatNumber(circuit.protectionRatedCurrent)}</td>
+              <td className="text-end">
+                {formatValue(circuit.protectionRatedCurrent, "protectionRatedCurrent")}
+              </td>
               <td>{circuit.protectionCharacteristic ?? "-"}</td>
               <td>{circuit.cableType ?? "-"}</td>
               <td>{circuit.cableCrossSection ?? "-"}</td>
-              <td className="text-end">{formatNumber(circuit.cableLength)}</td>
+              <td className="text-end">{formatValue(circuit.cableLength, "cableLength")}</td>
               <td>{circuit.remark ?? "-"}</td>
             </tr>
           );
@@ -146,25 +133,28 @@ function SectionRows(props: { section: CircuitTreeResponseDto["sections"][number
             <tr key={circuit.id} className={circuit.isReserve ? "reserve-row" : ""}>
               <td>{circuit.equipmentIdentifier}</td>
               <td>{row.displayName || row.name}</td>
-              <td>{formatPhaseType(row.phaseType)}</td>
+              <td>{formatValue(row.phaseType ?? undefined, "phaseType")}</td>
               <td>{row.connectionKind ?? "-"}</td>
               <td>{row.costGroup ?? "-"}</td>
               <td>{row.category ?? "-"}</td>
               <td>{row.level ?? "-"}</td>
               <td>{row.roomNumberSnapshot ?? "-"}</td>
               <td>{row.roomNameSnapshot ?? "-"}</td>
-              <td className="text-end">{formatNumber(row.quantity, 0)}</td>
+              <td className="text-end">{formatValue(row.quantity, "quantity")}</td>
-              <td className="text-end">{formatNumber(row.powerPerUnit)}</td>
+              <td className="text-end">{formatValue(row.powerPerUnit, "powerPerUnit")}</td>
-              <td className="text-end">{formatNumber(row.simultaneityFactor)}</td>
+              <td className="text-end">
-              <td className="text-end">{formatNumber(row.cosPhi)}</td>
+                {formatValue(row.simultaneityFactor, "simultaneityFactor")}
-              <td className="text-end">{formatNumber(row.rowTotalPower)}</td>
+              </td>
-              <td className="text-end">{formatNumber(circuit.circuitTotalPower)}</td>
+              <td className="text-end">{formatValue(row.cosPhi, "cosPhi")}</td>
+              <td className="text-end">{formatValue(row.rowTotalPower, "rowTotalPower")}</td>
               <td>{circuit.protectionType ?? "-"}</td>
-              <td className="text-end">{formatNumber(circuit.protectionRatedCurrent)}</td>
+              <td className="text-end">
+                {formatValue(circuit.protectionRatedCurrent, "protectionRatedCurrent")}
+              </td>
               <td>{circuit.protectionCharacteristic ?? "-"}</td>
               <td>{circuit.cableType ?? "-"}</td>
               <td>{circuit.cableCrossSection ?? "-"}</td>
-              <td className="text-end">{formatNumber(circuit.cableLength)}</td>
+              <td className="text-end">{formatValue(circuit.cableLength, "cableLength")}</td>
               <td>{row.remark ?? circuit.remark ?? "-"}</td>
             </tr>
           );
@@ -175,33 +165,38 @@ function SectionRows(props: { section: CircuitTreeResponseDto["sections"][number
             <tr key={`${circuit.id}-summary`} className="summary-row">
               <td>{circuit.equipmentIdentifier}</td>
               <td>{renderCircuitSummaryLabel(circuit)}</td>
-              <td colSpan={12}>-</td>
+              <td colSpan={11}>-</td>
-              <td className="text-end">{formatNumber(circuit.circuitTotalPower)}</td>
+              <td className="text-end">
+                {formatValue(circuit.circuitTotalPower, "circuitTotalPower")}
+              </td>
               <td>{circuit.protectionType ?? "-"}</td>
-              <td className="text-end">{formatNumber(circuit.protectionRatedCurrent)}</td>
+              <td className="text-end">
+                {formatValue(circuit.protectionRatedCurrent, "protectionRatedCurrent")}
+              </td>
               <td>{circuit.protectionCharacteristic ?? "-"}</td>
               <td>{circuit.cableType ?? "-"}</td>
               <td>{circuit.cableCrossSection ?? "-"}</td>
-              <td className="text-end">{formatNumber(circuit.cableLength)}</td>
+              <td className="text-end">{formatValue(circuit.cableLength, "cableLength")}</td>
               <td>{circuit.remark ?? "-"}</td>
             </tr>
             {circuit.deviceRows.map((row) => (
               <tr key={row.id} className="device-row">
                 <td className="text-muted"> </td>
                 <td className="indented-cell">{row.displayName || row.name}</td>
-                <td>{formatPhaseType(row.phaseType)}</td>
+                <td>{formatValue(row.phaseType ?? undefined, "phaseType")}</td>
                 <td>{row.connectionKind ?? "-"}</td>
                 <td>{row.costGroup ?? "-"}</td>
                 <td>{row.category ?? "-"}</td>
                 <td>{row.level ?? "-"}</td>
                 <td>{row.roomNumberSnapshot ?? "-"}</td>
                 <td>{row.roomNameSnapshot ?? "-"}</td>
-                <td className="text-end">{formatNumber(row.quantity, 0)}</td>
+                <td className="text-end">{formatValue(row.quantity, "quantity")}</td>
-                <td className="text-end">{formatNumber(row.powerPerUnit)}</td>
+                <td className="text-end">{formatValue(row.powerPerUnit, "powerPerUnit")}</td>
-                <td className="text-end">{formatNumber(row.simultaneityFactor)}</td>
+                <td className="text-end">
-                <td className="text-end">{formatNumber(row.cosPhi)}</td>
+                  {formatValue(row.simultaneityFactor, "simultaneityFactor")}
-                <td className="text-end">{formatNumber(row.rowTotalPower)}</td>
+                </td>
-                <td className="text-end">-</td>
+                <td className="text-end">{formatValue(row.cosPhi, "cosPhi")}</td>
+                <td className="text-end">{formatValue(row.rowTotalPower, "rowTotalPower")}</td>
                 <td>-</td>
                 <td className="text-end">-</td>
                 <td>-</td>
@@ -216,7 +211,7 @@ function SectionRows(props: { section: CircuitTreeResponseDto["sections"][number
       })}
       <tr className="placeholder-row">
         <td>-frei-</td>
-        <td colSpan={21}>Freie Zeile</td>
+        <td colSpan={20}>Freie Zeile</td>
       </tr>
     </>
   );

src/frontend/components/form-modal.tsx

@@ -0,0 +1,75 @@
+"use client";
+
+import React, { type FormEvent, type ReactNode } from "react";
+
+interface FormModalProps {
+  children: ReactNode;
+  description?: string;
+  isSaving: boolean;
+  onClose: () => void;
+  onSubmit: (event: FormEvent<HTMLFormElement>) => void;
+  submitDisabled?: boolean;
+  submitLabel: string;
+  title: string;
+}
+
+export function FormModal({
+  children,
+  description,
+  isSaving,
+  onClose,
+  onSubmit,
+  submitDisabled,
+  submitLabel,
+  title,
+}: FormModalProps) {
+  return (
+    <>
+      <div
+        aria-modal="true"
+        className="modal fade show d-block"
+        role="dialog"
+        tabIndex={-1}
+      >
+        <div className="modal-dialog modal-lg modal-dialog-centered">
+          <form className="modal-content" onSubmit={onSubmit}>
+            <div className="modal-header">
+              <div>
+                <h2 className="modal-title fs-5">{title}</h2>
+                {description ? (
+                  <p className="text-secondary small mb-0">{description}</p>
+                ) : null}
+              </div>
+              <button
+                aria-label="Schließen"
+                className="btn-close"
+                disabled={isSaving}
+                onClick={onClose}
+                type="button"
+              />
+            </div>
+            <div className="modal-body">{children}</div>
+            <div className="modal-footer">
+              <button
+                className="btn btn-outline-secondary"
+                disabled={isSaving}
+                onClick={onClose}
+                type="button"
+              >
+                Abbrechen
+              </button>
+              <button
+                className="btn btn-primary"
+                disabled={isSaving || submitDisabled}
+                type="submit"
+              >
+                {isSaving ? "Wird gespeichert …" : submitLabel}
+              </button>
+            </div>
+          </form>
+        </div>
+      </div>
+      <div className="modal-backdrop fade show" />
+    </>
+  );
+}

src/frontend/components/project-device-modal.tsx

@@ -0,0 +1,276 @@
+"use client";
+
+import React, { FormEvent, useState } from "react";
+import type {
+  CreateProjectDeviceInput,
+  GlobalDeviceDto,
+  ProjectDeviceDto,
+} from "../types";
+import { FormModal } from "./form-modal";
+
+interface ProjectDeviceModalProps {
+  globalDevices: GlobalDeviceDto[];
+  initialDevice?: ProjectDeviceDto;
+  isSaving: boolean;
+  onClose: () => void;
+  onImportGlobal: (globalDeviceId: string) => Promise<void>;
+  onSave: (input: CreateProjectDeviceInput) => Promise<void>;
+}
+
+export function ProjectDeviceModal({
+  globalDevices,
+  initialDevice,
+  isSaving,
+  onClose,
+  onImportGlobal,
+  onSave,
+}: ProjectDeviceModalProps) {
+  const [values, setValues] = useState(() => toFormValues(initialDevice));
+  const [selectedGlobalDeviceId, setSelectedGlobalDeviceId] = useState("");
+
+  function update(key: keyof typeof values, value: string) {
+    setValues((current) => ({ ...current, [key]: value }));
+  }
+
+  async function handleSubmit(event: FormEvent<HTMLFormElement>) {
+    event.preventDefault();
+    await onSave({
+      name: values.name.trim(),
+      displayName: values.displayName.trim() || values.name.trim(),
+      phaseType:
+        values.phaseType === "three_phase" ? "three_phase" : "single_phase",
+      connectionKind: optionalString(values.connectionKind),
+      costGroup: optionalString(values.costGroup),
+      category: optionalString(values.category),
+      quantity: Number(values.quantity),
+      powerPerUnit: Number(values.powerPerUnit),
+      simultaneityFactor: Number(values.simultaneityFactor),
+      cosPhi: optionalNumber(values.cosPhi),
+      remark: optionalString(values.remark),
+    });
+  }
+
+  const isValid =
+    values.name.trim().length > 0 &&
+    Number(values.quantity) >= 0 &&
+    Number(values.powerPerUnit) >= 0 &&
+    Number(values.simultaneityFactor) >= 0 &&
+    Number(values.simultaneityFactor) <= 1;
+
+  return (
+    <FormModal
+      description={
+        initialDevice
+          ? "Kanonische Gerätedaten bearbeiten; verknüpfte Stromkreiszeilen werden nicht automatisch überschrieben."
+          : "Ein Gerät manuell anlegen oder aus der globalen Bibliothek übernehmen."
+      }
+      isSaving={isSaving}
+      onClose={onClose}
+      onSubmit={handleSubmit}
+      submitDisabled={!isValid}
+      submitLabel={initialDevice ? "Änderungen speichern" : "Gerät anlegen"}
+      title={initialDevice ? "Projektgerät bearbeiten" : "Projektgerät hinzufügen"}
+    >
+      {!initialDevice && globalDevices.length > 0 ? (
+        <div className="border rounded p-3 mb-4">
+          <label className="form-label" htmlFor="global-project-device">
+            Aus globaler Gerätebibliothek
+          </label>
+          <div className="input-group">
+            <select
+              className="form-select"
+              id="global-project-device"
+              onChange={(event) => setSelectedGlobalDeviceId(event.target.value)}
+              value={selectedGlobalDeviceId}
+            >
+              <option value="">Gerät auswählen</option>
+              {globalDevices.map((device) => (
+                <option key={device.id} value={device.id}>
+                  {device.displayName}
+                </option>
+              ))}
+            </select>
+            <button
+              className="btn btn-outline-primary"
+              disabled={isSaving || !selectedGlobalDeviceId}
+              onClick={() => void onImportGlobal(selectedGlobalDeviceId)}
+              type="button"
+            >
+              Übernehmen
+            </button>
+          </div>
+        </div>
+      ) : null}
+
+      <div className="row g-3">
+        <TextField
+          id="device-name"
+          label="Interner Name"
+          onChange={(value) => update("name", value)}
+          required
+          value={values.name}
+        />
+        <TextField
+          id="device-display-name"
+          label="Anzeigename"
+          onChange={(value) => update("displayName", value)}
+          value={values.displayName}
+        />
+        <TextField
+          id="device-category"
+          label="Kategorie"
+          onChange={(value) => update("category", value)}
+          value={values.category}
+        />
+        <TextField
+          id="device-connection"
+          label="Anschlussart"
+          onChange={(value) => update("connectionKind", value)}
+          value={values.connectionKind}
+        />
+        <TextField
+          id="device-cost-group"
+          label="Kostengruppe"
+          onChange={(value) => update("costGroup", value)}
+          value={values.costGroup}
+        />
+        <div className="col-12 col-md-6">
+          <label className="form-label" htmlFor="device-phase-type">
+            Phasenart
+          </label>
+          <select
+            className="form-select"
+            id="device-phase-type"
+            onChange={(event) => update("phaseType", event.target.value)}
+            value={values.phaseType}
+          >
+            <option value="single_phase">1-phasig</option>
+            <option value="three_phase">3-phasig</option>
+          </select>
+        </div>
+        <NumberField
+          id="device-quantity"
+          label="Anzahl"
+          min="0"
+          onChange={(value) => update("quantity", value)}
+          value={values.quantity}
+        />
+        <NumberField
+          id="device-power"
+          label="Leistung je Stück [kW]"
+          min="0"
+          onChange={(value) => update("powerPerUnit", value)}
+          step="0.01"
+          value={values.powerPerUnit}
+        />
+        <NumberField
+          id="device-simultaneity"
+          label="Gleichzeitigkeitsfaktor"
+          max="1"
+          min="0"
+          onChange={(value) => update("simultaneityFactor", value)}
+          step="0.01"
+          value={values.simultaneityFactor}
+        />
+        <NumberField
+          id="device-cos-phi"
+          label="cos Phi"
+          max="1"
+          min="0"
+          onChange={(value) => update("cosPhi", value)}
+          step="0.01"
+          value={values.cosPhi}
+        />
+        <div className="col-12">
+          <label className="form-label" htmlFor="device-remark">
+            Bemerkung
+          </label>
+          <textarea
+            className="form-control"
+            id="device-remark"
+            onChange={(event) => update("remark", event.target.value)}
+            rows={3}
+            value={values.remark}
+          />
+        </div>
+      </div>
+    </FormModal>
+  );
+}
+
+interface FieldProps {
+  id: string;
+  label: string;
+  onChange: (value: string) => void;
+  required?: boolean;
+  value: string;
+}
+
+function TextField({ id, label, onChange, required, value }: FieldProps) {
+  return (
+    <div className="col-12 col-md-6">
+      <label className="form-label" htmlFor={id}>
+        {label}
+      </label>
+      <input
+        className="form-control"
+        id={id}
+        onChange={(event) => onChange(event.target.value)}
+        required={required}
+        value={value}
+      />
+    </div>
+  );
+}
+
+function NumberField({
+  id,
+  label,
+  max,
+  min,
+  onChange,
+  step,
+  value,
+}: FieldProps & { max?: string; min?: string; step?: string }) {
+  return (
+    <div className="col-12 col-md-6">
+      <label className="form-label" htmlFor={id}>
+        {label}
+      </label>
+      <input
+        className="form-control"
+        id={id}
+        max={max}
+        min={min}
+        onChange={(event) => onChange(event.target.value)}
+        step={step}
+        type="number"
+        value={value}
+      />
+    </div>
+  );
+}
+
+function toFormValues(device?: ProjectDeviceDto) {
+  return {
+    name: device?.name ?? "",
+    displayName: device?.displayName ?? "",
+    phaseType: device?.phaseType ?? "single_phase",
+    connectionKind: device?.connectionKind ?? "",
+    costGroup: device?.costGroup ?? "",
+    category: device?.category ?? "",
+    quantity: String(device?.quantity ?? 1),
+    powerPerUnit: String(device?.powerPerUnit ?? 0.1),
+    simultaneityFactor: String(device?.simultaneityFactor ?? 1),
+    cosPhi: String(device?.cosPhi ?? 1),
+    remark: device?.remark ?? "",
+  };
+}
+
+function optionalString(value: string) {
+  return value.trim() || undefined;
+}
+
+function optionalNumber(value: string) {
+  return value.trim() ? Number(value) : undefined;
+}

src/frontend/components/project-settings-modal.tsx

@@ -0,0 +1,426 @@
+"use client";
+
+import React, { FormEvent, useState } from "react";
+import type { ProjectDto } from "../types";
+import {
+  distributionBoardSupplyTypeLabels,
+  distributionBoardSupplyTypes,
+  type DistributionBoardSupplyType,
+} from "../../shared/constants/distribution-board";
+
+export interface ProjectSettingsInput {
+  name: string;
+  internalProjectNumber: string | null;
+  externalProjectNumber: string | null;
+  buildingOwner: string | null;
+  description: string | null;
+  singlePhaseVoltageV: number;
+  threePhaseVoltageV: number;
+  enabledDistributionBoardSupplyTypes: DistributionBoardSupplyType[];
+}
+
+interface ProjectSettingsModalProps {
+  isSaving: boolean;
+  onClose: () => void;
+  onExport: () => Promise<void>;
+  onImport: (
+    transfer: unknown,
+    mode: "replace" | "duplicate"
+  ) => Promise<void>;
+  onSave: (input: ProjectSettingsInput) => Promise<void>;
+  project: ProjectDto;
+  usedDistributionBoardSupplyTypes: DistributionBoardSupplyType[];
+}
+
+export function ProjectSettingsModal({
+  isSaving,
+  onClose,
+  onExport,
+  onImport,
+  onSave,
+  project,
+  usedDistributionBoardSupplyTypes,
+}: ProjectSettingsModalProps) {
+  const [name, setName] = useState(project.name);
+  const [internalProjectNumber, setInternalProjectNumber] = useState(
+    project.internalProjectNumber ?? ""
+  );
+  const [externalProjectNumber, setExternalProjectNumber] = useState(
+    project.externalProjectNumber ?? ""
+  );
+  const [buildingOwner, setBuildingOwner] = useState(
+    project.buildingOwner ?? ""
+  );
+  const [description, setDescription] = useState(
+    project.description ?? ""
+  );
+  const [singlePhaseVoltageV, setSinglePhaseVoltageV] = useState(
+    String(project.singlePhaseVoltageV)
+  );
+  const [threePhaseVoltageV, setThreePhaseVoltageV] = useState(
+    String(project.threePhaseVoltageV)
+  );
+  const [
+    enabledDistributionBoardSupplyTypes,
+    setEnabledDistributionBoardSupplyTypes,
+  ] = useState<DistributionBoardSupplyType[]>(
+    project.enabledDistributionBoardSupplyTypes
+  );
+  const [transfer, setTransfer] = useState<unknown>(null);
+  const [transferFilename, setTransferFilename] = useState("");
+  const [importMode, setImportMode] = useState<"replace" | "duplicate">(
+    "duplicate"
+  );
+  const [replaceConfirmed, setReplaceConfirmed] = useState(false);
+  const [fileError, setFileError] = useState<string | null>(null);
+
+  async function handleSubmit(event: FormEvent<HTMLFormElement>) {
+    event.preventDefault();
+    await onSave({
+      name: name.trim(),
+      internalProjectNumber: toNullableString(internalProjectNumber),
+      externalProjectNumber: toNullableString(externalProjectNumber),
+      buildingOwner: toNullableString(buildingOwner),
+      description: toNullableString(description),
+      singlePhaseVoltageV: Number(singlePhaseVoltageV),
+      threePhaseVoltageV: Number(threePhaseVoltageV),
+      enabledDistributionBoardSupplyTypes,
+    });
+  }
+
+  const isValid =
+    name.trim().length > 0 &&
+    Number(singlePhaseVoltageV) > 0 &&
+    Number(threePhaseVoltageV) > 0 &&
+    enabledDistributionBoardSupplyTypes.length > 0;
+
+  function toggleSupplyType(supplyType: DistributionBoardSupplyType) {
+    if (
+      enabledDistributionBoardSupplyTypes.includes(supplyType) &&
+      usedDistributionBoardSupplyTypes.includes(supplyType)
+    ) {
+      return;
+    }
+    setEnabledDistributionBoardSupplyTypes((current) =>
+      current.includes(supplyType)
+        ? current.filter((entry) => entry !== supplyType)
+        : distributionBoardSupplyTypes.filter(
+            (entry) => entry === supplyType || current.includes(entry)
+          )
+    );
+  }
+
+  async function handleTransferFile(file: File | undefined) {
+    setTransfer(null);
+    setTransferFilename("");
+    setFileError(null);
+    if (!file) {
+      return;
+    }
+    try {
+      setTransfer(JSON.parse(await file.text()) as unknown);
+      setTransferFilename(file.name);
+    } catch {
+      setFileError("Die ausgewählte Datei enthält kein gültiges JSON.");
+    }
+  }
+
+  return (
+    <>
+      <div
+        aria-labelledby="project-settings-title"
+        aria-modal="true"
+        className="modal fade show d-block"
+        role="dialog"
+        tabIndex={-1}
+      >
+        <div className="modal-dialog modal-lg modal-dialog-centered">
+          <form className="modal-content" onSubmit={handleSubmit}>
+            <div className="modal-header">
+              <div>
+                <h2 className="modal-title fs-5" id="project-settings-title">
+                  Projekteinstellungen
+                </h2>
+                <p className="text-secondary small mb-0">
+                  Stammdaten und elektrische Standardwerte des Projekts
+                </p>
+              </div>
+              <button
+                aria-label="Schließen"
+                className="btn-close"
+                disabled={isSaving}
+                onClick={onClose}
+                type="button"
+              />
+            </div>
+            <div className="modal-body">
+              <div className="row g-3">
+                <div className="col-12">
+                  <label className="form-label" htmlFor="project-name">
+                    Projektname
+                  </label>
+                  <input
+                    autoFocus
+                    className="form-control"
+                    id="project-name"
+                    maxLength={200}
+                    onChange={(event) => setName(event.target.value)}
+                    required
+                    value={name}
+                  />
+                </div>
+                <div className="col-12 col-md-6">
+                  <label className="form-label" htmlFor="internal-project-number">
+                    Projektnummer intern
+                  </label>
+                  <input
+                    className="form-control"
+                    id="internal-project-number"
+                    maxLength={100}
+                    onChange={(event) =>
+                      setInternalProjectNumber(event.target.value)
+                    }
+                    value={internalProjectNumber}
+                  />
+                </div>
+                <div className="col-12 col-md-6">
+                  <label className="form-label" htmlFor="external-project-number">
+                    Projektnummer extern
+                  </label>
+                  <input
+                    className="form-control"
+                    id="external-project-number"
+                    maxLength={100}
+                    onChange={(event) =>
+                      setExternalProjectNumber(event.target.value)
+                    }
+                    value={externalProjectNumber}
+                  />
+                </div>
+                <div className="col-12">
+                  <fieldset>
+                    <legend className="form-label mb-1">
+                      Verwendete Netzarten
+                    </legend>
+                    <p className="form-text mt-0">
+                      Nur ausgewählte Netzarten stehen bei Verteilungen zur
+                      Auswahl. Bereits verwendete Netzarten können nicht
+                      deaktiviert werden.
+                    </p>
+                    <div className="row g-2">
+                      {distributionBoardSupplyTypes.map((supplyType) => (
+                        <div
+                          className="col-12 col-md-6"
+                          key={supplyType}
+                        >
+                          <label className="form-check">
+                            <input
+                              checked={enabledDistributionBoardSupplyTypes.includes(
+                                supplyType
+                              )}
+                              className="form-check-input"
+                              disabled={usedDistributionBoardSupplyTypes.includes(
+                                supplyType
+                              )}
+                              onChange={() => toggleSupplyType(supplyType)}
+                              type="checkbox"
+                            />
+                            <span className="form-check-label">
+                              {distributionBoardSupplyTypeLabels[supplyType]}
+                              {usedDistributionBoardSupplyTypes.includes(
+                                supplyType
+                              )
+                                ? " (in Verwendung)"
+                                : ""}
+                            </span>
+                          </label>
+                        </div>
+                      ))}
+                    </div>
+                    {enabledDistributionBoardSupplyTypes.length === 0 ? (
+                      <div className="text-danger small mt-2">
+                        Mindestens eine Netzart muss aktiviert sein.
+                      </div>
+                    ) : null}
+                  </fieldset>
+                </div>
+                <div className="col-12">
+                  <label className="form-label" htmlFor="building-owner">
+                    Bauherr
+                  </label>
+                  <input
+                    className="form-control"
+                    id="building-owner"
+                    maxLength={200}
+                    onChange={(event) => setBuildingOwner(event.target.value)}
+                    value={buildingOwner}
+                  />
+                </div>
+                <div className="col-12">
+                  <label className="form-label" htmlFor="project-description">
+                    Beschreibung
+                  </label>
+                  <textarea
+                    className="form-control"
+                    id="project-description"
+                    maxLength={2000}
+                    onChange={(event) => setDescription(event.target.value)}
+                    rows={4}
+                    value={description}
+                  />
+                </div>
+                <div className="col-12 col-md-6">
+                  <label className="form-label" htmlFor="single-phase-voltage">
+                    Standardspannung 1-phasig [V]
+                  </label>
+                  <input
+                    className="form-control"
+                    id="single-phase-voltage"
+                    min="1"
+                    onChange={(event) =>
+                      setSinglePhaseVoltageV(event.target.value)
+                    }
+                    required
+                    type="number"
+                    value={singlePhaseVoltageV}
+                  />
+                </div>
+                <div className="col-12 col-md-6">
+                  <label className="form-label" htmlFor="three-phase-voltage">
+                    Standardspannung 3-phasig [V]
+                  </label>
+                  <input
+                    className="form-control"
+                    id="three-phase-voltage"
+                    min="1"
+                    onChange={(event) =>
+                      setThreePhaseVoltageV(event.target.value)
+                    }
+                    required
+                    type="number"
+                    value={threePhaseVoltageV}
+                  />
+                </div>
+                <div className="col-12">
+                  <hr className="my-2" />
+                  <h3 className="h6">Projekt importieren oder exportieren</h3>
+                  <p className="text-secondary small">
+                    Der Export enthält den vollständigen unterstützten
+                    Projektzustand. Beim Duplizieren bleibt dieses Projekt
+                    unverändert.
+                  </p>
+                  <button
+                    className="btn btn-outline-primary mb-3"
+                    disabled={isSaving}
+                    onClick={() => void onExport()}
+                    type="button"
+                  >
+                    Projektdatei herunterladen
+                  </button>
+                  <label className="form-label d-block" htmlFor="project-import">
+                    Projektdatei auswählen
+                  </label>
+                  <input
+                    accept=".json,application/json"
+                    className="form-control"
+                    id="project-import"
+                    onChange={(event) =>
+                      void handleTransferFile(event.target.files?.[0])
+                    }
+                    type="file"
+                  />
+                  {transferFilename ? (
+                    <div className="form-text">{transferFilename} ist bereit.</div>
+                  ) : null}
+                  {fileError ? (
+                    <div className="text-danger small mt-1">{fileError}</div>
+                  ) : null}
+                  <div className="d-flex flex-wrap gap-3 mt-3">
+                    <label className="form-check">
+                      <input
+                        checked={importMode === "duplicate"}
+                        className="form-check-input"
+                        name="import-mode"
+                        onChange={() => setImportMode("duplicate")}
+                        type="radio"
+                      />
+                      <span className="form-check-label">
+                        Als neues Projekt duplizieren
+                      </span>
+                    </label>
+                    <label className="form-check">
+                      <input
+                        checked={importMode === "replace"}
+                        className="form-check-input"
+                        name="import-mode"
+                        onChange={() => setImportMode("replace")}
+                        type="radio"
+                      />
+                      <span className="form-check-label">
+                        Dieses Projekt ersetzen
+                      </span>
+                    </label>
+                  </div>
+                  {importMode === "replace" ? (
+                    <label className="form-check mt-2">
+                      <input
+                        checked={replaceConfirmed}
+                        className="form-check-input"
+                        onChange={(event) =>
+                          setReplaceConfirmed(event.target.checked)
+                        }
+                        type="checkbox"
+                      />
+                      <span className="form-check-label text-danger">
+                        Ich bestätige, dass der aktuelle Projektstand ersetzt
+                        wird.
+                      </span>
+                    </label>
+                  ) : null}
+                  <button
+                    className="btn btn-outline-danger mt-3"
+                    disabled={
+                      isSaving ||
+                      transfer === null ||
+                      (importMode === "replace" && !replaceConfirmed)
+                    }
+                    onClick={() =>
+                      transfer === null
+                        ? undefined
+                        : void onImport(transfer, importMode)
+                    }
+                    type="button"
+                  >
+                    Projektdatei importieren
+                  </button>
+                </div>
+              </div>
+            </div>
+            <div className="modal-footer">
+              <button
+                className="btn btn-outline-secondary"
+                disabled={isSaving}
+                onClick={onClose}
+                type="button"
+              >
+                Abbrechen
+              </button>
+              <button
+                className="btn btn-primary"
+                disabled={isSaving || !isValid}
+                type="submit"
+              >
+                {isSaving ? "Wird gespeichert …" : "Einstellungen speichern"}
+              </button>
+            </div>
+          </form>
+        </div>
+      </div>
+      <div className="modal-backdrop fade show" />
+    </>
+  );
+}
+
+function toNullableString(value: string) {
+  return value.trim() || null;
+}

src/frontend/components/project-version-history.tsx

@@ -25,6 +25,7 @@ import {
   getProjectRevisionDescription,
   getProjectRevisionSourceLabel,
   getProjectSnapshotKindLabel,
+  getProjectSnapshotRevisionDescription,
   mergeProjectRevisionPages,
 } from "../utils/project-version-history";
 
@@ -343,7 +344,7 @@ export function ProjectVersionHistory({
               <thead>
                 <tr>
                   <th>Name</th>
-                  <th>Projektstand</th>
+                  <th>Gesicherter Projektstand</th>
                   <th>Erstellt</th>
                   <th className="text-end">Aktion</th>
                 </tr>
@@ -368,7 +369,16 @@ export function ProjectVersionHistory({
                         </div>
                       ) : null}
                     </td>
-                    <td>Revision {snapshot.sourceRevision}</td>
+                    <td>
+                      <strong>
+                        {snapshot.sourceRevision === 0
+                          ? "Ausgangsstand"
+                          : `Revision ${snapshot.sourceRevision}`}
+                      </strong>
+                      <div className="small text-secondary">
+                        {getProjectSnapshotRevisionDescription(snapshot)}
+                      </div>
+                    </td>
                     <td>{formatDateTime(snapshot.createdAtIso)}</td>
                     <td className="text-end">
                       <button

src/frontend/types.ts

@@ -1,8 +1,15 @@
+import type { DistributionBoardSupplyType } from "../shared/constants/distribution-board";
+
 export interface ProjectDto {
   id: string;
   name: string;
+  internalProjectNumber: string | null;
+  externalProjectNumber: string | null;
+  buildingOwner: string | null;
+  description: string | null;
   singlePhaseVoltageV: number;
   threePhaseVoltageV: number;
+  enabledDistributionBoardSupplyTypes: DistributionBoardSupplyType[];
   currentRevision: number;
 }
 
@@ -45,6 +52,7 @@ export interface ProjectSnapshotMetadataDto {
   id: string;
   projectId: string;
   sourceRevision: number;
+  sourceRevisionMetadata: ProjectRevisionSummaryDto | null;
   schemaVersion: number;
   kind: "named" | "automatic";
   name: string;
@@ -85,6 +93,9 @@ export interface DistributionBoardDto {
   id: string;
   projectId: string;
   name: string;
+  floorId: string | null;
+  supplyType: DistributionBoardSupplyType | null;
+  simultaneityFactor: number;
 }
 
 export interface DistributionBoardCommandResultDto
@@ -178,8 +189,7 @@ export interface CreateGlobalDeviceInput {
   quantity: number;
   installedPowerPerUnitKw: number;
   demandFactor: number;
-  voltageV?: number;
+  phaseCount: 1 | 3;
-  phaseCount?: 1 | 3;
   powerFactor?: number;
   note?: string;
 }
@@ -196,7 +206,6 @@ export interface CreateProjectDeviceInput {
   simultaneityFactor: number;
   cosPhi?: number;
   remark?: string;
-  voltageV?: number;
 }
 
 export interface ProjectDeviceSyncDifferenceDto {
@@ -288,6 +297,7 @@ export interface CircuitTreeSectionDto {
   displayName: string;
   prefix: string;
   sortOrder: number;
+  sectionTotalPower: number;
   circuits: CircuitTreeCircuitDto[];
 }
 
@@ -305,6 +315,11 @@ export interface CircuitTreeMigrationReportDto {
 export interface CircuitTreeResponseDto {
   circuitListId: string;
   currentRevision: number;
+  singlePhaseVoltageV: number;
+  threePhaseVoltageV: number;
+  distributionBoardSimultaneityFactor: number;
+  distributionBoardTotalPower: number;
+  distributionBoardTotalPowerWithSimultaneityFactor: number;
   sections: CircuitTreeSectionDto[];
   migrationReport?: CircuitTreeMigrationReportDto;
 }

src/frontend/utils/api.ts

@@ -64,7 +64,15 @@ async function request<T>(url: string, init?: RequestInit): Promise<T> {
   });
 
   if (!response.ok) {
-    const details = await response.text();
+    let details = await response.text();
+    try {
+      const parsed = JSON.parse(details) as { error?: unknown };
+      if (typeof parsed.error === "string") {
+        details = parsed.error;
+      }
+    } catch {
+      // Keep non-JSON error responses unchanged.
+    }
     throw new Error(details || `Anfrage fehlgeschlagen (Status ${response.status})`);
   }
 
@@ -210,7 +218,16 @@ export function createProject(name: string) {
 export function updateProjectSettings(
   projectId: string,
   expectedRevision: number,
-  input: { singlePhaseVoltageV: number; threePhaseVoltageV: number }
+  input: {
+    name: string;
+    internalProjectNumber: string | null;
+    externalProjectNumber: string | null;
+    buildingOwner: string | null;
+    description: string | null;
+    singlePhaseVoltageV: number;
+    threePhaseVoltageV: number;
+    enabledDistributionBoardSupplyTypes: ProjectDto["enabledDistributionBoardSupplyTypes"];
+  }
 ) {
   return request<ProjectSettingsCommandResultDto>(
     `/api/projects/${projectId}`,
@@ -221,20 +238,76 @@ export function updateProjectSettings(
   );
 }
 
+export function exportProjectTransfer(projectId: string) {
+  return request<unknown>(`/api/projects/${projectId}/export`);
+}
+
+export function importProjectTransferAsNew(transfer: unknown) {
+  return request<{ projectId: string; name: string }>(
+    "/api/projects/import",
+    {
+      method: "POST",
+      body: JSON.stringify({ transfer }),
+    }
+  );
+}
+
+export function importProjectTransfer(
+  projectId: string,
+  mode: "replace" | "duplicate",
+  expectedRevision: number,
+  transfer: unknown
+) {
+  return request<
+    | { projectId: string; name: string }
+    | ProjectSettingsCommandResultDto
+  >(`/api/projects/${projectId}/import`, {
+    method: "POST",
+    body: JSON.stringify(
+      mode === "replace"
+        ? { mode, expectedRevision, transfer }
+        : { mode, transfer }
+    ),
+  });
+}
+
 export function listDistributionBoards(projectId: string) {
   return request<DistributionBoardDto[]>(`/api/projects/${projectId}/distribution-boards`);
 }
 
 export function createDistributionBoard(
   projectId: string,
-  name: string,
+  input: {
+    name: string;
+    floorId: string | null;
+    supplyType: NonNullable<DistributionBoardDto["supplyType"]>;
+  },
   expectedRevision: number
 ) {
   return request<DistributionBoardCommandResultDto>(
     `/api/projects/${projectId}/distribution-boards`,
     {
       method: "POST",
-      body: JSON.stringify({ name, expectedRevision }),
+      body: JSON.stringify({ ...input, expectedRevision }),
+    }
+  );
+}
+
+export function updateDistributionBoard(
+  projectId: string,
+  distributionBoardId: string,
+  input: {
+    floorId: string | null;
+    supplyType: NonNullable<DistributionBoardDto["supplyType"]>;
+    simultaneityFactor: number;
+  },
+  expectedRevision: number
+) {
+  return request<DistributionBoardCommandResultDto>(
+    `/api/projects/${projectId}/distribution-boards/${distributionBoardId}`,
+    {
+      method: "PUT",
+      body: JSON.stringify({ ...input, expectedRevision }),
     }
   );
 }

src/frontend/utils/circuit-grid-model.ts

@@ -49,6 +49,7 @@ export type GridValue = string | number | boolean | undefined;
 export interface ColumnDef {
   key: CellKey;
   label: string;
+  fullLabel?: string;
   numeric?: boolean;
   defaultVisible?: boolean;
   locked?: boolean;
@@ -57,36 +58,64 @@ export interface ColumnDef {
 // BMK stays locked as the first column because circuit identity and circuit drag
 // handles depend on an always-visible equipment identifier.
 export const allColumns: ColumnDef[] = [
-  { key: "equipmentIdentifier", label: "Betriebsmittelkennzeichen", defaultVisible: true, locked: true },
+  {
+    key: "equipmentIdentifier",
+    label: "SK-Nr.",
+    fullLabel: "Stromkreisnummer / Betriebsmittelkennzeichen",
+    defaultVisible: true,
+    locked: true,
+  },
   { key: "displayName", label: "Anzeigename", defaultVisible: true },
   { key: "quantity", label: "Anzahl", numeric: true, defaultVisible: true },
-  { key: "powerPerUnit", label: "Leistung / Gerät", numeric: true, defaultVisible: true },
+  {
-  { key: "simultaneityFactor", label: "Gleichzeitigkeit", numeric: true, defaultVisible: true },
+    key: "powerPerUnit",
-  { key: "rowTotalPower", label: "Zeilensumme", numeric: true, defaultVisible: true },
+    label: "P/Stk. [kW]",
-  { key: "circuitTotalPower", label: "Stromkreissumme", numeric: true, defaultVisible: true },
+    fullLabel: "Leistung je Gerät [kW]",
+    numeric: true,
+    defaultVisible: true,
+  },
+  {
+    key: "simultaneityFactor",
+    label: "GZF",
+    fullLabel: "Gleichzeitigkeitsfaktor",
+    numeric: true,
+    defaultVisible: true,
+  },
+  {
+    key: "rowTotalPower",
+    label: "Ges.-Leistung [kW]",
+    fullLabel: "Gesamtleistung [kW]",
+    numeric: true,
+    defaultVisible: true,
+  },
   { key: "protectionSummary", label: "Schutz", defaultVisible: true },
   { key: "cableSummary", label: "Kabel", defaultVisible: true },
   { key: "roomSummary", label: "Raum", defaultVisible: true },
   { key: "remark", label: "Bemerkung", defaultVisible: true },
-  { key: "technicalName", label: "Technischer Name" },
+  { key: "technicalName", label: "Techn. Name", fullLabel: "Technischer Name" },
-  { key: "connectionKind", label: "Anschlussart" },
+  { key: "connectionKind", label: "Anschluss", fullLabel: "Anschlussart" },
   { key: "phaseType", label: "Phasenart" },
-  { key: "costGroup", label: "Kostengruppe" },
+  { key: "costGroup", label: "KG", fullLabel: "Kostengruppe" },
   { key: "category", label: "Kategorie" },
   { key: "level", label: "Ebene" },
-  { key: "roomNumberSnapshot", label: "Raumnummer" },
+  { key: "roomNumberSnapshot", label: "Raum-Nr.", fullLabel: "Raumnummer" },
   { key: "roomNameSnapshot", label: "Raumname" },
   { key: "cosPhi", label: "cos φ", numeric: true },
   { key: "protectionType", label: "Schutzart" },
-  { key: "protectionRatedCurrent", label: "Bemessungsstrom", numeric: true },
+  {
+    key: "protectionRatedCurrent",
+    label: "Bem.-Strom",
+    fullLabel: "Bemessungsstrom",
+    numeric: true,
+  },
   { key: "protectionCharacteristic", label: "Charakteristik" },
   { key: "cableType", label: "Kabeltyp" },
-  { key: "cableCrossSection", label: "Kabelquerschnitt" },
+  { key: "cableCrossSection", label: "Querschnitt", fullLabel: "Kabelquerschnitt" },
   { key: "cableLength", label: "Kabellänge", numeric: true },
   { key: "rcdAssignment", label: "RCD-Zuordnung" },
-  { key: "terminalDesignation", label: "Klemmenbezeichnung" },
+  { key: "terminalDesignation", label: "Klemme", fullLabel: "Klemmenbezeichnung" },
   { key: "voltage", label: "Spannung", numeric: true },
-  { key: "controlRequirement", label: "Steuerungsanforderung" },
+  { key: "controlRequirement", label: "Steuerung", fullLabel: "Steuerungsanforderung" },
   { key: "status", label: "Status" },
   { key: "isReserve", label: "Reserve" },
 ];
@@ -95,6 +124,96 @@ export const defaultVisibleColumnKeys = allColumns
   .filter((column) => column.defaultVisible)
   .map((column) => column.key);
 
+const projectColumnLayoutStoragePrefix =
+  "circuitTreeEditor.columnLayout.v2";
+
+export interface CircuitColumnLayout {
+  order: CellKey[];
+  visible: CellKey[];
+}
+
+const circuitSectionLabels: Record<string, string> = {
+  lighting: "Licht",
+  single_phase: "Einphasig",
+  three_phase: "Dreiphasig",
+  unassigned: "Nicht zugeordnet",
+};
+
+export function getCircuitSectionLabel(
+  section: { key: string; displayName: string }
+): string {
+  return circuitSectionLabels[section.key] ?? section.displayName;
+}
+
+export function getProjectColumnLayoutStorageKey(
+  projectId: string
+): string {
+  return `${projectColumnLayoutStoragePrefix}.${projectId}`;
+}
+
+export function normalizeColumnOrder(keys: CellKey[]): CellKey[] {
+  const unique = [...new Set(keys)];
+  const allKeys = allColumns.map((column) => column.key);
+  const merged = [
+    ...unique,
+    ...allKeys.filter((key) => !unique.includes(key)),
+  ];
+  return [
+    "equipmentIdentifier",
+    ...merged.filter((key) => key !== "equipmentIdentifier"),
+  ];
+}
+
+export function parseStoredColumnLayout(
+  serialized: string | null
+): CircuitColumnLayout | null {
+  if (!serialized) {
+    return null;
+  }
+  try {
+    const parsed = JSON.parse(serialized) as {
+      order?: unknown;
+      visible?: unknown;
+    };
+    if (
+      !Array.isArray(parsed.order) ||
+      !Array.isArray(parsed.visible)
+    ) {
+      return null;
+    }
+    const validKeys = new Set(
+      allColumns.map((column) => column.key)
+    );
+    const order = parsed.order.filter(
+      (key): key is CellKey =>
+        typeof key === "string" &&
+        validKeys.has(key as CellKey)
+    );
+    const visible = [
+      ...new Set(
+        parsed.visible.filter(
+          (key): key is CellKey =>
+            typeof key === "string" &&
+            validKeys.has(key as CellKey)
+        )
+      ),
+    ];
+    if (
+      !order.length ||
+      !visible.length ||
+      !visible.includes("equipmentIdentifier")
+    ) {
+      return null;
+    }
+    return {
+      order: normalizeColumnOrder(order),
+      visible,
+    };
+  } catch {
+    return null;
+  }
+}
+
 const deviceOnlyColumns = new Set<CellKey>([
   "quantity",
   "powerPerUnit",
@@ -162,23 +281,87 @@ const circuitFieldKeys = new Set<CellKey>([
   "cableSummary",
   "rcdAssignment",
   "terminalDesignation",
-  "voltage",
   "controlRequirement",
   "status",
   "isReserve",
   "remark",
 ]);
 
-export function formatValue(value: GridValue): string {
+const numberFormatters = new Map<number, Intl.NumberFormat>();
+
+function formatNumber(value: number, maximumFractionDigits: number): string {
+  let formatter = numberFormatters.get(maximumFractionDigits);
+  if (!formatter) {
+    formatter = new Intl.NumberFormat("de-DE", {
+      maximumFractionDigits,
+      minimumFractionDigits: 0,
+      useGrouping: false,
+    });
+    numberFormatters.set(maximumFractionDigits, formatter);
+  }
+  return formatter.format(value);
+}
+
+function getMaximumFractionDigits(key: CellKey | undefined): number {
+  if (
+    key === "powerPerUnit" ||
+    key === "rowTotalPower" ||
+    key === "circuitTotalPower"
+  ) {
+    return 3;
+  }
+  if (
+    key === "simultaneityFactor" ||
+    key === "cosPhi" ||
+    key === "protectionRatedCurrent" ||
+    key === "cableLength"
+  ) {
+    return 2;
+  }
+  if (key === "voltage") {
+    return 0;
+  }
+  return 3;
+}
+
+export function formatValue(value: GridValue, key?: CellKey): string {
   if (value === undefined || value === null || value === "") {
     return "-";
   }
   if (typeof value === "boolean") {
     return value ? "Ja" : "Nein";
   }
+  if (typeof value === "number") {
+    return formatNumber(value, getMaximumFractionDigits(key));
+  }
+  if (key === "phaseType") {
+    return formatPhaseTypeLabel(String(value));
+  }
   return String(value);
 }
 
+export function formatPhaseTypeLabel(value: string): string {
+  if (value === "single_phase") {
+    return "1-phasig";
+  }
+  if (value === "three_phase") {
+    return "3-phasig";
+  }
+  return value;
+}
+
+export function isGridEditorControlTarget(target: unknown): boolean {
+  if (
+    target === null ||
+    typeof target !== "object" ||
+    !("closest" in target) ||
+    typeof target.closest !== "function"
+  ) {
+    return false;
+  }
+  return Boolean(target.closest("input, select, textarea"));
+}
+
 export function parseNumeric(cellKey: CellKey, draft: string): number | undefined {
   const trimmed = draft.trim();
   if (trimmed === "") {
@@ -317,12 +500,15 @@ export function getCircuitValue(circuit: CircuitTreeCircuitDto, key: CellKey): G
   }
 }
 
-export function normalizeFilterValue(value: GridValue): string {
+export function normalizeFilterValue(key: CellKey, value: GridValue): string {
-  return formatValue(value);
+  return formatValue(value, key);
 }
 
 export function getBlockSortValue(circuit: CircuitTreeCircuitDto, key: CellKey): GridValue {
   const firstRow = circuit.deviceRows[0];
+  if (key === "rowTotalPower") {
+    return circuit.circuitTotalPower;
+  }
   if (circuitOnlyColumns.has(key)) {
     return getCircuitValue(circuit, key);
   }
@@ -351,6 +537,7 @@ export function compareSortValues(left: GridValue, right: GridValue): number {
 
 export function getCellKind(rowType: RowType, key: CellKey): CellKind {
   if (key === "rowTotalPower" || key === "circuitTotalPower") return "computed";
+  if (key === "voltage") return "readonly";
   if (rowType === "section") return "readonly";
   if (rowType === "placeholder") {
     if (deviceFieldKeys.has(key)) return "deviceField";

src/frontend/utils/circuit-grid-projection.ts

@@ -47,16 +47,19 @@ export interface VisibleGridRow {
 
 function getCircuitBlockFilterValues(circuit: CircuitTreeCircuitDto, key: CellKey): Set<string> {
   const values = new Set<string>();
+  if (key === "rowTotalPower") {
+    values.add(normalizeFilterValue(key, circuit.circuitTotalPower));
+  }
   if (circuitOnlyColumns.has(key) || key === "displayName" || key === "remark") {
-    values.add(normalizeFilterValue(getCircuitValue(circuit, key)));
+    values.add(normalizeFilterValue(key, getCircuitValue(circuit, key)));
   }
   if (!circuitOnlyColumns.has(key)) {
     for (const device of circuit.deviceRows) {
-      values.add(normalizeFilterValue(getDeviceValue(device, key)));
+      values.add(normalizeFilterValue(key, getDeviceValue(device, key)));
     }
   }
   if (values.size === 0 && deviceFieldKeys.has(key)) {
-    values.add(normalizeFilterValue(undefined));
+    values.add(normalizeFilterValue(key, undefined));
   }
   return values;
 }
@@ -140,10 +143,14 @@ function makeVisibleGridRow(
       value = getDeviceValue(device, column.key);
     } else if (kind === "circuitField" && circuit) {
       value = getCircuitValue(circuit, column.key);
-    } else if (column.key === "circuitTotalPower" && circuit) {
-      value = circuit.circuitTotalPower;
     } else if (column.key === "rowTotalPower" && device) {
       value = device.rowTotalPower;
+    } else if (column.key === "rowTotalPower" && circuit) {
+      value = circuit.circuitTotalPower;
+    } else if (column.key === "circuitTotalPower" && circuit) {
+      value = circuit.circuitTotalPower;
+    } else if (column.key === "voltage" && circuit) {
+      value = circuit.voltage;
     }
 
     return { cellKey: column.key, editable, kind, value };

src/frontend/utils/project-version-history.ts

@@ -31,6 +31,7 @@ const commandTypeLabels: Record<string, string> = {
   "project-device.sync-rows": "Projektgerät-Verknüpfungen geändert",
   "project.update-settings": "Projekteinstellungen bearbeitet",
   "distribution-board.insert": "Verteilung angelegt",
+  "distribution-board.update": "Verteilung bearbeitet",
   "distribution-board.delete": "Verteilung entfernt",
   "project-floor.insert": "Geschoss angelegt",
   "project-floor.delete": "Geschoss entfernt",
@@ -48,8 +49,15 @@ export function getProjectRevisionSourceLabel(
 export function getProjectRevisionDescription(
   revision: ProjectRevisionSummaryDto
 ) {
+  const description = revision.description?.trim();
+  if (
+    description === `Undo ${revision.commandType}` ||
+    description === `Redo ${revision.commandType}`
+  ) {
+    return commandTypeLabels[revision.commandType] || revision.commandType;
+  }
   return (
-    revision.description?.trim() ||
+    description ||
     commandTypeLabels[revision.commandType] ||
     revision.commandType
   );
@@ -61,6 +69,26 @@ export function getProjectSnapshotKindLabel(
   return kind === "automatic" ? "Automatisch" : "Benannt";
 }
 
+export function getProjectSnapshotRevisionDescription(
+  snapshot: ProjectSnapshotMetadataDto
+) {
+  if (snapshot.sourceRevision === 0) {
+    return "Projektstart";
+  }
+  if (
+    !snapshot.sourceRevisionMetadata ||
+    snapshot.sourceRevisionMetadata.revisionNumber !==
+      snapshot.sourceRevision
+  ) {
+    return "Änderungsdetails nicht verfügbar";
+  }
+  return `${getProjectRevisionSourceLabel(
+    snapshot.sourceRevisionMetadata.source
+  )}: ${getProjectRevisionDescription(
+    snapshot.sourceRevisionMetadata
+  )}`;
+}
+
 export function mergeProjectRevisionPages(
   current: ProjectRevisionSummaryDto[],
   next: ProjectRevisionSummaryDto[]

src/server/composition/project-transfer-store.ts

@@ -0,0 +1,4 @@
+import { db } from "../../db/client.js";
+import { ProjectTransferRepository } from "../../db/repositories/project-transfer.repository.js";
+
+export const projectTransferStore = new ProjectTransferRepository(db);

src/server/controllers/circuit-tree.controller.ts

@@ -1,7 +1,10 @@
 import type { Request, Response } from "express";
 import {
+  applyDistributionBoardSimultaneityFactor,
   calculateCircuitTotalPower,
+  calculateDistributionBoardTotalPower,
   calculateRowTotalPower,
+  calculateSectionTotalPower,
 } from "../../domain/calculations/circuit-power-calculation.js";
 import type { CircuitTreeResponse } from "../../domain/models/circuit-tree.model.js";
 import {
@@ -9,6 +12,7 @@ import {
   circuitListRepository,
   circuitRepository,
   circuitSectionRepository,
+  distributionBoardRepository,
   projectRepository,
 } from "../composition/application-repositories.js";
 
@@ -37,6 +41,16 @@ export async function getCircuitTree(req: Request, res: Response) {
   if (!project) {
     return res.status(404).json({ error: "Project not found" });
   }
+  const distributionBoard =
+    await distributionBoardRepository.findById(
+      projectId,
+      list.distributionBoardId
+    );
+  if (!distributionBoard) {
+    return res.status(404).json({
+      error: "Distribution board not found",
+    });
+  }
 
   try {
     const sections = await circuitSectionRepository.listByCircuitList(circuitListId);
@@ -55,12 +69,19 @@ export async function getCircuitTree(req: Request, res: Response) {
     const tree: CircuitTreeResponse = {
       circuitListId,
       currentRevision: project.currentRevision,
+      singlePhaseVoltageV: project.singlePhaseVoltageV,
+      threePhaseVoltageV: project.threePhaseVoltageV,
+      distributionBoardSimultaneityFactor:
+        distributionBoard.simultaneityFactor,
+      distributionBoardTotalPower: 0,
+      distributionBoardTotalPowerWithSimultaneityFactor: 0,
       sections: sections.map((section) => ({
         id: section.id,
         key: section.key,
         displayName: section.displayName,
         prefix: section.prefix,
         sortOrder: section.sortOrder,
+        sectionTotalPower: 0,
         circuits: [],
       })),
     };
@@ -121,12 +142,31 @@ export async function getCircuitTree(req: Request, res: Response) {
       });
     }
 
+    for (const section of tree.sections) {
+      section.sectionTotalPower = calculateSectionTotalPower(
+        section.circuits
+      );
+    }
+    tree.distributionBoardTotalPower =
+      calculateDistributionBoardTotalPower(tree.sections);
+    tree.distributionBoardTotalPowerWithSimultaneityFactor =
+      applyDistributionBoardSimultaneityFactor(
+        tree.distributionBoardTotalPower,
+        tree.distributionBoardSimultaneityFactor
+      );
+
     return res.json(tree);
   } catch (error) {
     if (isMissingCircuitTreeSchemaError(error)) {
       return res.json({
         circuitListId,
         currentRevision: project.currentRevision,
+        singlePhaseVoltageV: project.singlePhaseVoltageV,
+        threePhaseVoltageV: project.threePhaseVoltageV,
+        distributionBoardSimultaneityFactor:
+          distributionBoard.simultaneityFactor,
+        distributionBoardTotalPower: 0,
+        distributionBoardTotalPowerWithSimultaneityFactor: 0,
         sections: [],
         warning:
           "Circuit-first tables are not available yet. Run database migrations (including 0008_circuit_first_model).",

src/server/controllers/distribution-board.controller.ts

@@ -1,9 +1,13 @@
 import type { Request, Response } from "express";
+import { createDistributionBoardUpdateProjectCommand } from "../../domain/models/distribution-board-project-command.model.js";
 import {
   createDistributionBoardInsertProjectCommand,
   createDistributionBoardStructureSnapshot,
 } from "../../domain/models/distribution-board-structure-project-command.model.js";
-import { createDistributionBoardSchema } from "../../shared/validation/project-structure.schemas.js";
+import {
+  createDistributionBoardSchema,
+  updateDistributionBoardSchema,
+} from "../../shared/validation/project-structure.schemas.js";
 import { projectCommandService } from "../composition/project-command-stores.js";
 import { distributionBoardRepository } from "../composition/application-repositories.js";
 import { respondWithProjectCommandError } from "./project-command.controller.js";
@@ -31,7 +35,11 @@ export async function createDistributionBoard(req: Request, res: Response) {
 
   const structure = createDistributionBoardStructureSnapshot(
     projectId,
-    parsed.data.name
+    parsed.data.name,
+    {
+      floorId: parsed.data.floorId,
+      supplyType: parsed.data.supplyType,
+    }
   );
   try {
     const result = projectCommandService.executeUser({
@@ -43,9 +51,53 @@ export async function createDistributionBoard(req: Request, res: Response) {
     });
     return res.status(201).json({
       ...result,
-      distributionBoard: structure.distributionBoard,
+      distributionBoard: {
+        ...structure.distributionBoard,
+        simultaneityFactor: 1,
+      },
     });
   } catch (error) {
     return respondWithProjectCommandError(error, res);
   }
 }
+
+export async function updateDistributionBoard(
+  req: Request,
+  res: Response
+) {
+  const { projectId, distributionBoardId } = req.params;
+  if (
+    typeof projectId !== "string" ||
+    typeof distributionBoardId !== "string"
+  ) {
+    return res.status(400).json({ error: "Invalid distribution board id" });
+  }
+  const parsed = updateDistributionBoardSchema.safeParse(req.body);
+  if (!parsed.success) {
+    return res.status(400).json({ error: parsed.error.flatten() });
+  }
+  try {
+    const result = projectCommandService.executeUser({
+      projectId,
+      expectedRevision: parsed.data.expectedRevision,
+      description: "Verteilung bearbeiten",
+      command: createDistributionBoardUpdateProjectCommand(
+        distributionBoardId,
+        {
+          floorId: parsed.data.floorId,
+          supplyType: parsed.data.supplyType,
+          simultaneityFactor: parsed.data.simultaneityFactor,
+        }
+      ),
+    });
+    const distributionBoard = (
+      await distributionBoardRepository.listByProject(projectId)
+    ).find((board) => board.id === distributionBoardId);
+    if (!distributionBoard) {
+      return res.status(404).json({ error: "Distribution board not found" });
+    }
+    return res.json({ ...result, distributionBoard });
+  } catch (error) {
+    return respondWithProjectCommandError(error, res);
+  }
+}

src/server/controllers/global-device.controller.ts

@@ -70,7 +70,6 @@ export async function copyProjectDeviceToGlobal(req: Request, res: Response) {
     quantity: source.quantity,
     installedPowerPerUnitKw: source.powerPerUnit,
     demandFactor: source.simultaneityFactor,
-    voltageV: source.voltageV ?? undefined,
     phaseCount: source.phaseType === "three_phase" ? 3 : 1,
     powerFactor: source.cosPhi ?? undefined,
     note: source.remark ?? undefined,

src/server/controllers/project-device.controller.ts

@@ -11,6 +11,7 @@ import { projectCommandService } from "../composition/project-command-stores.js"
 import {
   globalDeviceRepository,
   projectDeviceRepository,
+  projectRepository,
 } from "../composition/application-repositories.js";
 import {
   createProjectDeviceCommandSchema,
@@ -21,6 +22,7 @@ import {
 } from "../../shared/validation/project-device.schemas.js";
 import type { CreateProjectDeviceInput } from "../../shared/validation/project-device.schemas.js";
 import { respondWithProjectCommandError } from "./project-command.controller.js";
+import { resolveProjectVoltage } from "../../domain/services/project-voltage.service.js";
 
 export async function listProjectDevicesByProject(req: Request, res: Response) {
   const { projectId } = req.params;
@@ -41,9 +43,18 @@ export async function createProjectDevice(req: Request, res: Response) {
     return res.status(400).json({ error: parsed.error.flatten() });
   }
   const { expectedRevision, ...input } = parsed.data;
-  const projectDevice = toProjectDeviceSnapshot(projectId, randomUUID(), input);
 
   try {
+    const project = await projectRepository.findById(projectId);
+    if (!project) {
+      return res.status(404).json({ error: "Project not found" });
+    }
+    const projectDevice = toProjectDeviceSnapshot(
+      projectId,
+      randomUUID(),
+      input,
+      project
+    );
     const result = projectCommandService.executeUser({
       projectId,
       expectedRevision,
@@ -73,13 +84,17 @@ export async function updateProjectDevice(req: Request, res: Response) {
   const { expectedRevision, ...input } = parsed.data;
 
   try {
+    const project = await projectRepository.findById(projectId);
+    if (!project) {
+      return res.status(404).json({ error: "Project not found" });
+    }
     const result = projectCommandService.executeUser({
       projectId,
       expectedRevision,
       description: "Projektgerät bearbeiten",
       command: createProjectDeviceUpdateProjectCommand(
         projectDeviceId,
-        toProjectDeviceValues(input)
+        toProjectDeviceValues(input, project)
       ),
     });
     // Linked rows are synchronized only through the explicit review flow.
@@ -133,6 +148,10 @@ export async function copyGlobalDeviceToProject(req: Request, res: Response) {
   if (!source) {
     return res.status(404).json({ error: "Global device not found" });
   }
+  const project = await projectRepository.findById(projectId);
+  if (!project) {
+    return res.status(404).json({ error: "Project not found" });
+  }
 
   const projectDevice = toProjectDeviceSnapshot(projectId, randomUUID(), {
     name: source.name,
@@ -144,8 +163,7 @@ export async function copyGlobalDeviceToProject(req: Request, res: Response) {
     simultaneityFactor: source.demandFactor,
     cosPhi: source.powerFactor ?? undefined,
     remark: source.note ?? undefined,
-    voltageV: source.voltageV ?? undefined,
+  }, project);
-  });
 
   try {
     const result = projectCommandService.executeUser({
@@ -167,16 +185,26 @@ export async function copyGlobalDeviceToProject(req: Request, res: Response) {
 function toProjectDeviceSnapshot(
   projectId: string,
   id: string,
-  input: CreateProjectDeviceInput
+  input: CreateProjectDeviceInput,
+  project: {
+    singlePhaseVoltageV: number;
+    threePhaseVoltageV: number;
+  }
 ): ProjectDeviceSnapshot {
   return {
     id,
     projectId,
-    ...toProjectDeviceValues(input),
+    ...toProjectDeviceValues(input, project),
   };
 }
 
-function toProjectDeviceValues(input: CreateProjectDeviceInput) {
+function toProjectDeviceValues(
+  input: CreateProjectDeviceInput,
+  project: {
+    singlePhaseVoltageV: number;
+    threePhaseVoltageV: number;
+  }
+) {
   return {
     name: input.name,
     displayName: input.displayName,
@@ -189,7 +217,7 @@ function toProjectDeviceValues(input: CreateProjectDeviceInput) {
     simultaneityFactor: input.simultaneityFactor,
     cosPhi: input.cosPhi ?? null,
     remark: input.remark ?? null,
-    voltageV: input.voltageV ?? null,
+    voltageV: resolveProjectVoltage(input.phaseType, project),
   };
 }
 

src/server/controllers/project-snapshot.controller.ts

@@ -6,7 +6,10 @@ import {
   createNamedProjectSnapshotSchema,
   restoreProjectSnapshotSchema,
 } from "../../shared/validation/project-snapshot.schemas.js";
-import { projectCommandService } from "../composition/project-command-stores.js";
+import {
+  projectCommandService,
+  projectHistoryStore,
+} from "../composition/project-command-stores.js";
 import { projectSnapshotStore } from "../composition/project-snapshot-store.js";
 
 export function listProjectSnapshots(req: Request, res: Response) {
@@ -18,7 +21,7 @@ export function listProjectSnapshots(req: Request, res: Response) {
   if (!snapshots) {
     return res.status(404).json({ error: "Project not found" });
   }
-  return res.json(snapshots);
+  return res.json(withSourceRevisionMetadata(projectId, snapshots));
 }
 
 export function createNamedProjectSnapshot(
@@ -43,7 +46,9 @@ export function createNamedProjectSnapshot(
     if (!snapshot) {
       return res.status(404).json({ error: "Project not found" });
     }
-    return res.status(201).json(snapshot);
+    return res
+      .status(201)
+      .json(withSourceRevisionMetadata(projectId, [snapshot])[0]);
   } catch (error) {
     if (error instanceof ProjectRevisionConflictError) {
       return res.status(409).json({
@@ -97,7 +102,9 @@ export function restoreProjectSnapshot(
       command: prepared.command,
     });
     return res.json({
-      snapshot: prepared.snapshot,
+      snapshot: withSourceRevisionMetadata(projectId, [
+        prepared.snapshot,
+      ])[0],
       revision: result.revision,
       history: result.history,
     });
@@ -120,6 +127,29 @@ export function restoreProjectSnapshot(
   }
 }
 
+function withSourceRevisionMetadata<
+  TSnapshot extends { sourceRevision: number },
+>(
+  projectId: string,
+  snapshots: TSnapshot[]
+) {
+  const revisions = projectHistoryStore.listRevisionsByNumbers(
+    projectId,
+    snapshots.map((snapshot) => snapshot.sourceRevision)
+  );
+  const revisionByNumber = new Map(
+    revisions.map((revision) => [
+      revision.revisionNumber,
+      revision,
+    ])
+  );
+  return snapshots.map((snapshot) => ({
+    ...snapshot,
+    sourceRevisionMetadata:
+      revisionByNumber.get(snapshot.sourceRevision) ?? null,
+  }));
+}
+
 function getProjectId(req: Request, res: Response) {
   const { projectId } = req.params;
   if (typeof projectId !== "string" || !projectId.trim()) {

src/server/controllers/project-transfer.controller.ts

@@ -0,0 +1,128 @@
+import type { NextFunction, Request, Response } from "express";
+import { ProjectRevisionConflictError } from "../../domain/errors/project-revision-conflict.error.js";
+import { ProjectStateConflictError } from "../../domain/errors/project-state-conflict.error.js";
+import {
+  importProjectTransferAsNewSchema,
+  importProjectTransferSchema,
+} from "../../shared/validation/project-transfer.schemas.js";
+import { projectCommandService } from "../composition/project-command-stores.js";
+import { projectTransferStore } from "../composition/project-transfer-store.js";
+
+export function exportProjectTransfer(req: Request, res: Response) {
+  const projectId = getProjectId(req, res);
+  if (!projectId) {
+    return;
+  }
+  const transfer = projectTransferStore.exportProject(projectId);
+  if (!transfer) {
+    return res.status(404).json({ error: "Project not found" });
+  }
+  const filename = safeFilename(transfer.projectState.project.name);
+  res.setHeader(
+    "Content-Disposition",
+    `attachment; filename="${filename}.leistungsbilanz.json"`
+  );
+  return res.json(transfer);
+}
+
+export function importProjectTransferAsNewProject(
+  req: Request,
+  res: Response,
+  next: NextFunction
+) {
+  const parsed = importProjectTransferAsNewSchema.safeParse(req.body);
+  if (!parsed.success) {
+    return res.status(400).json({ error: parsed.error.flatten() });
+  }
+  try {
+    return res
+      .status(201)
+      .json(projectTransferStore.importDuplicate(parsed.data.transfer));
+  } catch (error) {
+    if (
+      error instanceof Error &&
+      (error.message.startsWith("Project transfer") ||
+        error.message.startsWith("Snapshot"))
+    ) {
+      return res.status(400).json({ error: error.message });
+    }
+    return next(error);
+  }
+}
+
+export function importProjectTransfer(
+  req: Request,
+  res: Response,
+  next: NextFunction
+) {
+  const projectId = getProjectId(req, res);
+  if (!projectId) {
+    return;
+  }
+  const parsed = importProjectTransferSchema.safeParse(req.body);
+  if (!parsed.success) {
+    return res.status(400).json({ error: parsed.error.flatten() });
+  }
+  try {
+    if (parsed.data.mode === "duplicate") {
+      return res
+        .status(201)
+        .json(projectTransferStore.importDuplicate(parsed.data.transfer));
+    }
+    const prepared = projectTransferStore.prepareReplace(
+      projectId,
+      parsed.data.transfer
+    );
+    if (!prepared) {
+      return res.status(404).json({ error: "Project not found" });
+    }
+    const result = projectCommandService.executeRestore({
+      projectId,
+      expectedRevision: parsed.data.expectedRevision,
+      description: "Projektimport wiederherstellen",
+      command: prepared.command,
+    });
+    return res.json(result);
+  } catch (error) {
+    if (error instanceof ProjectRevisionConflictError) {
+      return res.status(409).json({
+        error: error.message,
+        code: "PROJECT_REVISION_CONFLICT",
+        expectedRevision: error.expectedRevision,
+        currentRevision: error.actualRevision,
+      });
+    }
+    if (error instanceof ProjectStateConflictError) {
+      return res
+        .status(409)
+        .json({ error: error.message, code: "PROJECT_STATE_CONFLICT" });
+    }
+    if (
+      error instanceof Error &&
+      (error.message.startsWith("Project transfer") ||
+        error.message.startsWith("Snapshot"))
+    ) {
+      return res.status(400).json({ error: error.message });
+    }
+    return next(error);
+  }
+}
+
+function getProjectId(req: Request, res: Response) {
+  const { projectId } = req.params;
+  if (typeof projectId !== "string" || !projectId.trim()) {
+    res.status(400).json({ error: "Invalid projectId" });
+    return null;
+  }
+  return projectId;
+}
+
+function safeFilename(name: string) {
+  return (
+    name
+      .normalize("NFKD")
+      .replace(/[^a-zA-Z0-9_-]+/g, "-")
+      .replace(/^-+|-+$/g, "")
+      .slice(0, 80) || "projekt"
+  );
+}

src/server/index.ts

@@ -8,7 +8,7 @@ import { errorMiddleware } from "./middleware/error.middleware.js";
 const app = express();
 const port = Number(process.env.PORT || 3000);
 
-app.use(express.json());
+app.use(express.json({ limit: "25mb" }));
 
 app.get("/health", (_req, res) => {
   res.json({ ok: true });

src/server/routes/project.routes.ts

@@ -8,6 +8,7 @@ import {
 import {
   createDistributionBoard,
   listDistributionBoardsByProject,
+  updateDistributionBoard,
 } from "../controllers/distribution-board.controller.js";
 import { listCircuitListsByProject } from "../controllers/circuit-list.controller.js";
 import { createFloor, listFloorsByProject } from "../controllers/floor.controller.js";
@@ -27,12 +28,20 @@ import {
   listProjectSnapshots,
   restoreProjectSnapshot,
 } from "../controllers/project-snapshot.controller.js";
+import {
+  exportProjectTransfer,
+  importProjectTransfer,
+  importProjectTransferAsNewProject,
+} from "../controllers/project-transfer.controller.js";
 
 export const projectRouter = Router();
 
 projectRouter.get("/", listProjects);
 projectRouter.post("/", createProject);
+projectRouter.post("/import", importProjectTransferAsNewProject);
 projectRouter.get("/:projectId", getProject);
+projectRouter.get("/:projectId/export", exportProjectTransfer);
+projectRouter.post("/:projectId/import", importProjectTransfer);
 projectRouter.get("/:projectId/history", getProjectHistory);
 projectRouter.get("/:projectId/history/revisions", listProjectRevisions);
 projectRouter.post("/:projectId/commands", executeProjectCommand);
@@ -47,6 +56,10 @@ projectRouter.post(
 projectRouter.put("/:projectId", updateProjectSettings);
 projectRouter.get("/:projectId/distribution-boards", listDistributionBoardsByProject);
 projectRouter.post("/:projectId/distribution-boards", createDistributionBoard);
+projectRouter.put(
+  "/:projectId/distribution-boards/:distributionBoardId",
+  updateDistributionBoard
+);
 projectRouter.get("/:projectId/circuit-lists", listCircuitListsByProject);
 projectRouter.get("/:projectId/circuit-lists/:circuitListId/tree", getCircuitTree);
 projectRouter.get("/:projectId/floors", listFloorsByProject);

src/shared/constants/distribution-board.ts

@@ -0,0 +1,26 @@
+export const distributionBoardSupplyTypes = [
+  "AV",
+  "SV",
+  "EV",
+  "USV",
+  "MSR",
+  "SiBe",
+] as const;
+
+export type DistributionBoardSupplyType =
+  (typeof distributionBoardSupplyTypes)[number];
+
+export const defaultDistributionBoardSupplyTypes: DistributionBoardSupplyType[] =
+  [...distributionBoardSupplyTypes];
+
+export const distributionBoardSupplyTypeLabels: Record<
+  DistributionBoardSupplyType,
+  string
+> = {
+  AV: "AV – Allgemeine Stromversorgung",
+  SV: "SV – Sicherheitsstromversorgung",
+  EV: "EV – Ersatzstromversorgung",
+  USV: "USV – Unterbrechungsfreie Stromversorgung",
+  MSR: "MSR – Mess-, Steuerungs- und Regelungstechnik",
+  SiBe: "SiBe – Sicherheitsbeleuchtung",
+};

src/shared/validation/global-device.schemas.ts

@@ -7,11 +7,10 @@ export const createGlobalDeviceSchema = z.object({
   quantity: z.number().min(0),
   installedPowerPerUnitKw: z.number().min(0),
   demandFactor: z.number().min(0).max(1),
-  voltageV: z.number().positive().optional(),
+  phaseCount: z.union([z.literal(1), z.literal(3)]),
-  phaseCount: z.union([z.literal(1), z.literal(3)]).optional(),
   powerFactor: z.number().min(0).max(1).optional(),
   note: z.string().optional(),
-});
+}).strict();
 
 export const updateGlobalDeviceSchema = createGlobalDeviceSchema;
 

src/shared/validation/project-device.schemas.ts

@@ -14,9 +14,7 @@ export const createProjectDeviceSchema = z.object({
   simultaneityFactor: z.number().min(0).max(1),
   cosPhi: z.number().min(0).max(1).optional(),
   remark: z.string().optional(),
-  // Transitional metadata used when importing from the legacy global-device library.
+}).strict();
-  voltageV: z.number().positive().optional(),
-});
 
 export const updateProjectDeviceSchema = createProjectDeviceSchema;
 

src/shared/validation/project-structure.schemas.ts

@@ -1,8 +1,13 @@
 import { z } from "zod";
+import { distributionBoardSupplyTypes } from "../constants/distribution-board.js";
 import { expectedProjectRevisionSchema } from "./project-command.schemas.js";
 
 export const createProjectSchema = z.object({
-  name: z.string().min(1),
+  name: z.string().trim().min(1).max(200),
+  internalProjectNumber: z.string().trim().max(100).optional(),
+  externalProjectNumber: z.string().trim().max(100).optional(),
+  buildingOwner: z.string().trim().max(200).optional(),
+  description: z.string().trim().max(2000).optional(),
   singlePhaseVoltageV: z.number().positive().optional(),
   threePhaseVoltageV: z.number().positive().optional(),
 });
@@ -10,8 +15,19 @@ export const createProjectSchema = z.object({
 export const updateProjectSettingsSchema = z
   .object({
     expectedRevision: expectedProjectRevisionSchema,
+    name: z.string().trim().min(1).max(200),
+    internalProjectNumber: z.string().trim().max(100).nullable(),
+    externalProjectNumber: z.string().trim().max(100).nullable(),
+    buildingOwner: z.string().trim().max(200).nullable(),
+    description: z.string().trim().max(2000).nullable(),
     singlePhaseVoltageV: z.number().positive(),
     threePhaseVoltageV: z.number().positive(),
+    enabledDistributionBoardSupplyTypes: z
+      .array(z.enum(distributionBoardSupplyTypes))
+      .min(1)
+      .refine((values) => new Set(values).size === values.length, {
+        message: "Netzarten dürfen nicht mehrfach ausgewählt werden.",
+      }),
   })
   .strict();
 
@@ -19,6 +35,17 @@ export const createDistributionBoardSchema = z
   .object({
     expectedRevision: expectedProjectRevisionSchema,
     name: z.string().trim().min(1),
+    floorId: z.string().trim().min(1).nullable(),
+    supplyType: z.enum(distributionBoardSupplyTypes),
+  })
+  .strict();
+
+export const updateDistributionBoardSchema = z
+  .object({
+    expectedRevision: expectedProjectRevisionSchema,
+    floorId: z.string().trim().min(1).nullable(),
+    supplyType: z.enum(distributionBoardSupplyTypes),
+    simultaneityFactor: z.number().finite().min(0).max(1),
   })
   .strict();
 

src/shared/validation/project-transfer.schemas.ts

@@ -0,0 +1,30 @@
+import { z } from "zod";
+import { expectedProjectRevisionSchema } from "./project-command.schemas.js";
+
+const requiredProjectTransferSchema = z
+  .unknown()
+  .refine((value) => value !== undefined, {
+    message: "Projektdatei fehlt.",
+  });
+
+export const importProjectTransferAsNewSchema = z
+  .object({
+    transfer: requiredProjectTransferSchema,
+  })
+  .strict();
+
+export const importProjectTransferSchema = z.discriminatedUnion("mode", [
+  z
+    .object({
+      mode: z.literal("replace"),
+      expectedRevision: expectedProjectRevisionSchema,
+      transfer: requiredProjectTransferSchema,
+    })
+    .strict(),
+  z
+    .object({
+      mode: z.literal("duplicate"),
+      transfer: requiredProjectTransferSchema,
+    })
+    .strict(),
+]);

tests/circuit-grid-model.test.ts

@@ -4,10 +4,15 @@ import {
   allColumns,
   buildCircuitEditPatch,
   buildDeviceRowEditPatch,
+  formatValue,
+  getCircuitSectionLabel,
+  getProjectColumnLayoutStorageKey,
+  isGridEditorControlTarget,
   getBlockSortValue,
   getCellKind,
   getCircuitValue,
   getDeviceValue,
+  parseStoredColumnLayout,
   parseNumeric,
 } from "../src/frontend/utils/circuit-grid-model.js";
 import type { CircuitTreeCircuitDto, CircuitTreeDeviceRowDto } from "../src/frontend/types.js";
@@ -49,11 +54,69 @@ const circuit: CircuitTreeCircuitDto = {
 };
 
 describe("circuit grid model", () => {
+  it("does not route clicks from active editor controls back to the grid cell", () => {
+    const inputTarget = {
+      closest: (selector: string) =>
+        selector === "input, select, textarea" ? {} : null,
+    };
+    const cellTarget = { closest: () => null };
+
+    assert.equal(isGridEditorControlTarget(inputTarget), true);
+    assert.equal(isGridEditorControlTarget(cellTarget), false);
+    assert.equal(isGridEditorControlTarget(null), false);
+  });
+
   it("keeps the equipment identifier locked as the first column", () => {
     assert.equal(allColumns[0].key, "equipmentIdentifier");
+    assert.equal(allColumns[0].label, "SK-Nr.");
+    assert.equal(
+      allColumns[0].fullLabel,
+      "Stromkreisnummer / Betriebsmittelkennzeichen"
+    );
     assert.equal(allColumns[0].locked, true);
   });
 
+  it("stores valid column layouts under a project-specific key", () => {
+    assert.equal(
+      getProjectColumnLayoutStorageKey("project-1"),
+      "circuitTreeEditor.columnLayout.v2.project-1"
+    );
+    const layout = parseStoredColumnLayout(
+      JSON.stringify({
+        order: ["displayName", "equipmentIdentifier"],
+        visible: [
+          "displayName",
+          "equipmentIdentifier",
+          "unknown",
+        ],
+      })
+    );
+    assert.ok(layout);
+    assert.equal(layout.order[0], "equipmentIdentifier");
+    assert.deepEqual(layout.visible, [
+      "displayName",
+      "equipmentIdentifier",
+    ]);
+    assert.equal(parseStoredColumnLayout("{invalid"), null);
+  });
+
+  it("shows stable circuit sections with German labels", () => {
+    assert.equal(
+      getCircuitSectionLabel({
+        key: "lighting",
+        displayName: "Lighting",
+      }),
+      "Licht"
+    );
+    assert.equal(
+      getCircuitSectionLabel({
+        key: "custom",
+        displayName: "Sonderbereich",
+      }),
+      "Sonderbereich"
+    );
+  });
+
   it("maps shared fields to the correct level for every row shape", () => {
     assert.equal(getCellKind("circuitCompact", "displayName"), "deviceField");
     assert.equal(getCellKind("circuitCompact", "equipmentIdentifier"), "circuitField");
@@ -76,6 +139,15 @@ describe("circuit grid model", () => {
     assert.equal(getCircuitValue(circuit, "cableSummary"), "NYM-J, 1.5 mm², 20 m");
   });
 
+  it("formats displayed numeric values without changing their stored precision", () => {
+    assert.equal(formatValue(0.123456, "powerPerUnit"), "0,123");
+    assert.equal(formatValue(0.87654, "simultaneityFactor"), "0,88");
+    assert.equal(formatValue(230.4, "voltage"), "230");
+    assert.equal(formatValue(16, "protectionRatedCurrent"), "16");
+    assert.equal(formatValue("single_phase", "phaseType"), "1-phasig");
+    assert.equal(formatValue("three_phase", "phaseType"), "3-phasig");
+  });
+
   it("uses circuit display values for block sorting and falls back to the first device", () => {
     assert.equal(getBlockSortValue(circuit, "displayName"), "Lighting circuit");
     assert.equal(getBlockSortValue({ ...circuit, displayName: undefined }, "displayName"), "Office light");

tests/circuit-grid-projection.test.ts

@@ -164,6 +164,15 @@ describe("circuit grid projection", () => {
       rows.at(-1)?.cells.find((cell) => cell.cellKey === "equipmentIdentifier")?.value,
       "-frei-"
     );
+    const circuitSummary = rows.find((row) => row.rowType === "circuitSummary");
+    assert.equal(
+      circuitSummary?.cells.find((cell) => cell.cellKey === "rowTotalPower")?.value,
+      multiDeviceCircuit.circuitTotalPower
+    );
+    assert.equal(
+      circuitSummary?.cells.some((cell) => cell.cellKey === "circuitTotalPower"),
+      false
+    );
   });
 
   it("collects filter options from both circuit and device values", () => {

tests/circuit-power-calculation.test.ts

@@ -1,9 +1,17 @@
 import assert from "node:assert/strict";
 import { describe, it } from "node:test";
 import {
+  applyDistributionBoardSimultaneityFactor,
   calculateCircuitTotalPower,
+  calculateDistributionBoardTotalPower,
   calculateRowTotalPower,
+  calculateSectionTotalPower,
 } from "../src/domain/calculations/circuit-power-calculation.js";
+import {
+  resolveCircuitPhaseType,
+  resolveProjectVoltage,
+  normalizeKnownElectricalPhaseType,
+} from "../src/domain/services/project-voltage.service.js";
 
 describe("circuit power calculation", () => {
   it("calculates row and circuit totals from device rows", () => {
@@ -14,5 +22,68 @@ describe("circuit power calculation", () => {
     ]);
     assert.equal(total, 4.5);
   });
+
+  it("calculates section and distribution-board totals", () => {
+    const lighting = calculateSectionTotalPower([
+      { circuitTotalPower: 1.5 },
+      { circuitTotalPower: 2.25 },
+    ]);
+    const singlePhase = calculateSectionTotalPower([
+      { circuitTotalPower: 3 },
+    ]);
+    const total = calculateDistributionBoardTotalPower([
+      { sectionTotalPower: lighting },
+      { sectionTotalPower: singlePhase },
+      { sectionTotalPower: 0 },
+    ]);
+
+    assert.equal(lighting, 3.75);
+    assert.equal(total, 6.75);
+    assert.equal(
+      applyDistributionBoardSimultaneityFactor(total, 0.8),
+      5.4
+    );
+    assert.throws(
+      () => applyDistributionBoardSimultaneityFactor(total, 1.1),
+      /between zero and one/
+    );
+  });
+});
+
+describe("project voltage derivation", () => {
+  const settings = {
+    singlePhaseVoltageV: 240,
+    threePhaseVoltageV: 415,
+  };
+
+  it("derives device voltage exclusively from phase and project settings", () => {
+    assert.equal(resolveProjectVoltage("single_phase", settings), 240);
+    assert.equal(resolveProjectVoltage("three_phase", settings), 415);
+  });
+
+  it("uses section phase and handles unassigned circuits conservatively", () => {
+    assert.equal(resolveCircuitPhaseType("lighting", ["three_phase"]), "single_phase");
+    assert.equal(resolveCircuitPhaseType("single_phase", ["three_phase"]), "single_phase");
+    assert.equal(resolveCircuitPhaseType("three_phase", ["single_phase"]), "three_phase");
+    assert.equal(resolveCircuitPhaseType("unassigned", ["three_phase"]), "three_phase");
+    assert.equal(
+      resolveCircuitPhaseType("unassigned", ["three_phase", "single_phase"]),
+      "single_phase"
+    );
+    assert.equal(resolveCircuitPhaseType("unassigned", []), "single_phase");
+    assert.equal(resolveCircuitPhaseType("unassigned", [null]), "single_phase");
+  });
+
+  it("normalizes known legacy phase labels without guessing unknown values", () => {
+    assert.equal(normalizeKnownElectricalPhaseType("1phasig"), "single_phase");
+    assert.equal(normalizeKnownElectricalPhaseType("1-phasig"), "single_phase");
+    assert.equal(normalizeKnownElectricalPhaseType("3phase"), "three_phase");
+    assert.equal(normalizeKnownElectricalPhaseType("3-phasig"), "three_phase");
+    assert.equal(normalizeKnownElectricalPhaseType(null), null);
+    assert.throws(
+      () => normalizeKnownElectricalPhaseType("zweiphasig"),
+      /Unknown electrical phase type/
+    );
+  });
 });
 

tests/circuit-project-command.repository.test.ts

@@ -129,7 +129,7 @@ describe("circuit project-command repository", () => {
       const circuit = getCircuit(fixture.context);
       assert.equal(circuit.displayName, null);
       assert.equal(circuit.protectionRatedCurrent, 16);
-      assert.equal(circuit.voltage, 400);
+      assert.equal(circuit.voltage, 230);
       assert.equal(circuit.controlRequirement, "DALI");
       assert.equal(circuit.isReserve, 1);
       assert.equal(executed.revision.revisionNumber, 1);
@@ -138,7 +138,6 @@ describe("circuit project-command repository", () => {
         changes: [
           { field: "displayName", value: "Licht Bestand" },
           { field: "protectionRatedCurrent", value: 10 },
-          { field: "voltage", value: 230 },
           { field: "controlRequirement", value: "none" },
           { field: "isReserve", value: false },
         ],
@@ -149,7 +148,15 @@ describe("circuit project-command repository", () => {
         .from(projectChangeSets)
         .get();
       assert.ok(changeSet);
-      assert.deepEqual(deserializeProjectCommand(changeSet.forwardPayloadJson), command);
+      assert.deepEqual(
+        deserializeProjectCommand(changeSet.forwardPayloadJson),
+        createCircuitUpdateProjectCommand("circuit-1", {
+          displayName: null,
+          protectionRatedCurrent: 16,
+          controlRequirement: "DALI",
+          isReserve: true,
+        })
+      );
       assert.deepEqual(
         deserializeProjectCommand(changeSet.inversePayloadJson),
         executed.inverse

tests/distribution-board-structure-project-command.repository.test.ts

@@ -13,14 +13,23 @@ import { circuitLists } from "../src/db/schema/circuit-lists.js";
 import { circuitSections } from "../src/db/schema/circuit-sections.js";
 import { circuits } from "../src/db/schema/circuits.js";
 import { distributionBoards } from "../src/db/schema/distribution-boards.js";
+import { floors } from "../src/db/schema/floors.js";
 import { projectRevisions } from "../src/db/schema/project-revisions.js";
 import { projects } from "../src/db/schema/projects.js";
 import { ProjectRevisionConflictError } from "../src/domain/errors/project-revision-conflict.error.js";
 import {
   createDistributionBoardInsertProjectCommand,
   createDistributionBoardStructureSnapshot,
+  type DistributionBoardStructureProjectCommand,
 } from "../src/domain/models/distribution-board-structure-project-command.model.js";
-import { createDistributionBoard } from "../src/frontend/utils/api.js";
+import {
+  createDistributionBoardUpdateProjectCommand,
+  type DistributionBoardUpdateProjectCommand,
+} from "../src/domain/models/distribution-board-project-command.model.js";
+import {
+  createDistributionBoard,
+  updateDistributionBoard,
+} from "../src/frontend/utils/api.js";
 
 function createTestDatabase(): DatabaseContext {
   const context = createDatabaseContext(":memory:");
@@ -50,9 +59,11 @@ describe("distribution-board structure project command", () => {
   it("builds the fixed setup and sends the expected frontend revision", async () => {
     const structure = createDistributionBoardStructureSnapshot(
       "project-1",
-      " UV-02 "
+      " UV-02 ",
+      { floorId: null, supplyType: "SV" }
     );
     assert.equal(structure.distributionBoard.name, "UV-02");
+    assert.equal(structure.distributionBoard.supplyType, "SV");
     assert.equal(
       structure.circuitList.name,
       "UV-02 Stromkreisliste"
@@ -91,14 +102,27 @@ describe("distribution-board structure project command", () => {
       });
     };
     try {
-      await createDistributionBoard("project-1", "UV-02", 7);
+      await createDistributionBoard(
+        "project-1",
+        {
+          name: "UV-02",
+          floorId: null,
+          supplyType: "SV",
+        },
+        7
+      );
     } finally {
       globalThis.fetch = originalFetch;
     }
     assert.deepEqual(requests, [
       {
         url: "/api/projects/project-1/distribution-boards",
-        body: { name: "UV-02", expectedRevision: 7 },
+        body: {
+          name: "UV-02",
+          floorId: null,
+          supplyType: "SV",
+          expectedRevision: 7,
+        },
       },
     ]);
   });
@@ -178,6 +202,306 @@ describe("distribution-board structure project command", () => {
     }
   });
 
+  it("allows only supply types enabled in the project", () => {
+    const context = createTestDatabase();
+    try {
+      context.db
+        .update(projects)
+        .set({
+          enabledDistributionBoardSupplyTypes: ["MSR", "SiBe"],
+        })
+        .where(eq(projects.id, "project-1"))
+        .run();
+      const repository =
+        new DistributionBoardStructureProjectCommandRepository(
+          context.db
+        );
+      assert.throws(
+        () =>
+          repository.execute({
+            projectId: "project-1",
+            expectedRevision: 0,
+            source: "user",
+            command: createDistributionBoardInsertProjectCommand(
+              createDistributionBoardStructureSnapshot(
+                "project-1",
+                "UV AV",
+                { floorId: null, supplyType: "AV" }
+              )
+            ),
+          }),
+        /nicht aktiviert/
+      );
+      const structure = createDistributionBoardStructureSnapshot(
+        "project-1",
+        "UV SiBe",
+        { floorId: null, supplyType: "SiBe" }
+      );
+      repository.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command: createDistributionBoardInsertProjectCommand(structure),
+      });
+      assert.equal(
+        context.db.select().from(distributionBoards).get()?.supplyType,
+        "SiBe"
+      );
+    } finally {
+      context.close();
+    }
+  });
+
+  it("applies stored version-one setup commands with unassigned new fields", () => {
+    const context = createTestDatabase();
+    try {
+      const repository =
+        new DistributionBoardStructureProjectCommandRepository(
+          context.db
+        );
+      const current = createDistributionBoardStructureSnapshot(
+        "project-1",
+        "UV Alt",
+        { floorId: null, supplyType: null }
+      );
+      const {
+        floorId: _floorId,
+        supplyType: _supplyType,
+        ...legacyBoard
+      } = current.distributionBoard;
+      const legacyCommand = {
+        schemaVersion: 1,
+        type: "distribution-board.insert",
+        payload: {
+          structure: {
+            ...current,
+            distributionBoard: legacyBoard,
+          },
+        },
+      } as unknown as DistributionBoardStructureProjectCommand;
+      repository.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command: legacyCommand,
+      });
+      const inserted = context.db
+        .select()
+        .from(distributionBoards)
+        .get();
+      assert.equal(inserted?.floorId, null);
+      assert.equal(inserted?.supplyType, null);
+    } finally {
+      context.close();
+    }
+  });
+
+  it("updates floor, supply type and simultaneity factor with persisted undo", () => {
+    const context = createTestDatabase();
+    try {
+      context.db
+        .insert(floors)
+        .values([
+          {
+            id: "floor-1",
+            projectId: "project-1",
+            name: "EG",
+            sortOrder: 10,
+          },
+          {
+            id: "floor-foreign",
+            projectId: "project-2",
+            name: "Fremd",
+            sortOrder: 10,
+          },
+        ])
+        .run();
+      const repository =
+        new DistributionBoardStructureProjectCommandRepository(
+          context.db
+        );
+      const structure = createDistributionBoardStructureSnapshot(
+        "project-1",
+        "UV-02",
+        { floorId: null, supplyType: "AV" }
+      );
+      repository.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command:
+          createDistributionBoardInsertProjectCommand(structure),
+      });
+      const forward = repository.executeUpdate({
+        projectId: "project-1",
+        expectedRevision: 1,
+        source: "user",
+        command: createDistributionBoardUpdateProjectCommand(
+          structure.distributionBoard.id,
+          {
+            floorId: "floor-1",
+            supplyType: "SV",
+            simultaneityFactor: 0.75,
+          }
+        ),
+      });
+      assert.deepEqual(
+        context.db
+          .select({
+            floorId: distributionBoards.floorId,
+            supplyType: distributionBoards.supplyType,
+            simultaneityFactor:
+              distributionBoards.simultaneityFactor,
+          })
+          .from(distributionBoards)
+          .get(),
+        {
+          floorId: "floor-1",
+          supplyType: "SV",
+          simultaneityFactor: 0.75,
+        }
+      );
+
+      const undoStep = new ProjectHistoryRepository(
+        context.db
+      ).getNextCommand("project-1", "undo");
+      assert.ok(undoStep);
+      repository.executeUpdate({
+        projectId: "project-1",
+        expectedRevision: 2,
+        source: "undo",
+        historyTargetChangeSetId: undoStep.changeSetId,
+        command: forward.inverse,
+      });
+      assert.deepEqual(
+        context.db
+          .select({
+            floorId: distributionBoards.floorId,
+            supplyType: distributionBoards.supplyType,
+            simultaneityFactor:
+              distributionBoards.simultaneityFactor,
+          })
+          .from(distributionBoards)
+          .get(),
+        {
+          floorId: null,
+          supplyType: "AV",
+          simultaneityFactor: 1,
+        }
+      );
+      assert.throws(
+        () =>
+          repository.executeUpdate({
+            projectId: "project-1",
+            expectedRevision: 3,
+            source: "user",
+            command: createDistributionBoardUpdateProjectCommand(
+              structure.distributionBoard.id,
+              { floorId: "floor-foreign" }
+            ),
+          }),
+        /does not belong/
+      );
+      assert.equal(
+        context.db
+          .select()
+          .from(projectRevisions)
+          .all().length,
+        3
+      );
+    } finally {
+      context.close();
+    }
+  });
+
+  it("keeps stored version-one board updates executable", () => {
+    const context = createTestDatabase();
+    try {
+      const repository =
+        new DistributionBoardStructureProjectCommandRepository(
+          context.db
+        );
+      const structure = createDistributionBoardStructureSnapshot(
+        "project-1",
+        "UV Alt",
+        { supplyType: "AV" }
+      );
+      repository.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command:
+          createDistributionBoardInsertProjectCommand(structure),
+      });
+      const legacyUpdate = {
+        schemaVersion: 1,
+        type: "distribution-board.update",
+        payload: {
+          distributionBoardId: structure.distributionBoard.id,
+          changes: [{ field: "supplyType", value: "SV" }],
+        },
+      } as DistributionBoardUpdateProjectCommand;
+
+      repository.executeUpdate({
+        projectId: "project-1",
+        expectedRevision: 1,
+        source: "user",
+        command: legacyUpdate,
+      });
+
+      const board = context.db
+        .select()
+        .from(distributionBoards)
+        .get();
+      assert.equal(board?.supplyType, "SV");
+      assert.equal(board?.simultaneityFactor, 1);
+    } finally {
+      context.close();
+    }
+  });
+
+  it("sends distribution-board updates to the revision-safe API", async () => {
+    const requests: Array<{ url: string; method: string; body: unknown }> = [];
+    const originalFetch = globalThis.fetch;
+    globalThis.fetch = async (input, init) => {
+      requests.push({
+        url: String(input),
+        method: init?.method ?? "GET",
+        body: JSON.parse(String(init?.body)),
+      });
+      return new Response(JSON.stringify({}), {
+        status: 200,
+        headers: { "Content-Type": "application/json" },
+      });
+    };
+    try {
+      await updateDistributionBoard(
+        "project-1",
+        "board-1",
+        {
+          floorId: "floor-1",
+          supplyType: "USV",
+          simultaneityFactor: 0.8,
+        },
+        9
+      );
+    } finally {
+      globalThis.fetch = originalFetch;
+    }
+    assert.deepEqual(requests, [
+      {
+        url: "/api/projects/project-1/distribution-boards/board-1",
+        method: "PUT",
+        body: {
+          floorId: "floor-1",
+          supplyType: "USV",
+          simultaneityFactor: 0.8,
+          expectedRevision: 9,
+        },
+      },
+    ]);
+  });
+
   it("rejects foreign, stale and changed structures without partial writes", () => {
     const context = createTestDatabase();
     try {

tests/project-command.service.test.ts

@@ -951,8 +951,21 @@ describe("project command service", () => {
         projectId: "project-1",
         expectedRevision: 0,
         command: createProjectSettingsUpdateProjectCommand({
+          name: "Test project",
+          internalProjectNumber: null,
+          externalProjectNumber: null,
+          buildingOwner: null,
+          description: null,
           singlePhaseVoltageV: 240,
           threePhaseVoltageV: 415,
+          enabledDistributionBoardSupplyTypes: [
+            "AV",
+            "SV",
+            "EV",
+            "USV",
+            "MSR",
+            "SiBe",
+          ],
         }),
       });
       assert.equal(updated.history.currentRevision, 1);

tests/project-device-schema.test.ts

@@ -41,6 +41,20 @@ describe("project device circuit-first schema", () => {
     assert.equal(result.success, false);
   });
 
+  it("rejects manually supplied device voltages", () => {
+    const result = createProjectDeviceSchema.safeParse({
+      name: "Pumpe",
+      displayName: "Pumpe",
+      phaseType: "three_phase",
+      quantity: 1,
+      powerPerUnit: 2,
+      simultaneityFactor: 1,
+      voltageV: 500,
+    });
+
+    assert.equal(result.success, false);
+  });
+
   it("requires a project revision for create and update commands", () => {
     const device = {
       name: "E-Line Pro",

tests/project-history.repository.test.ts

@@ -177,6 +177,33 @@ describe("project history repository", () => {
           nextBeforeRevision: null,
         }
       );
+      assert.deepEqual(
+        history
+          .listRevisionsByNumbers("project-1", [3, 1, 3, 99])
+          .map((revision) => ({
+            revisionNumber: revision.revisionNumber,
+            description: revision.description,
+          })),
+        [
+          {
+            revisionNumber: 3,
+            description: "Anzahl zurücknehmen",
+          },
+          {
+            revisionNumber: 1,
+            description: "Stromkreis umbenennen",
+          },
+        ]
+      );
+      assert.deepEqual(
+        history.listRevisionsByNumbers("project-1", [0]),
+        []
+      );
+      assert.throws(
+        () =>
+          history.listRevisionsByNumbers("project-1", [-1]),
+        /non-negative integers/
+      );
     } finally {
       context.close();
     }

tests/project-location-structure-project-command.repository.test.ts

@@ -10,6 +10,7 @@ import {
 import { ProjectHistoryRepository } from "../src/db/repositories/project-history.repository.js";
 import { ProjectLocationStructureProjectCommandRepository } from "../src/db/repositories/project-location-structure-project-command.repository.js";
 import { consumers } from "../src/db/schema/consumers.js";
+import { distributionBoards } from "../src/db/schema/distribution-boards.js";
 import { floors } from "../src/db/schema/floors.js";
 import { projectRevisions } from "../src/db/schema/project-revisions.js";
 import { projects } from "../src/db/schema/projects.js";
@@ -183,6 +184,52 @@ describe("project-location structure project command", () => {
     }
   });
 
+  it("does not undo a floor assigned to a distribution board", () => {
+    const context = createTestDatabase();
+    try {
+      const repository =
+        new ProjectLocationStructureProjectCommandRepository(context.db);
+      const floor = createProjectFloorSnapshot("project-1", "EG", 0);
+      const inserted = repository.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command: createProjectFloorInsertProjectCommand(floor),
+      });
+      context.db
+        .insert(distributionBoards)
+        .values({
+          id: "board-1",
+          projectId: "project-1",
+          name: "UV-01",
+          floorId: floor.id,
+          supplyType: "AV",
+        })
+        .run();
+      const undoStep = new ProjectHistoryRepository(
+        context.db
+      ).getNextCommand("project-1", "undo");
+      assert.ok(undoStep);
+      assert.throws(
+        () =>
+          repository.execute({
+            projectId: "project-1",
+            expectedRevision: 1,
+            source: "undo",
+            historyTargetChangeSetId: undoStep.changeSetId,
+            command: inserted.inverse,
+          }),
+        /assigned to a distribution board/
+      );
+      assert.equal(
+        context.db.select().from(projectRevisions).all().length,
+        1
+      );
+    } finally {
+      context.close();
+    }
+  });
+
   it("creates a stable room and supports persisted undo and redo", () => {
     const context = createTestDatabase();
     try {

tests/project-overview-import.test.ts

@@ -0,0 +1,84 @@
+import assert from "node:assert/strict";
+import { describe, it } from "node:test";
+import * as React from "react";
+import { renderToStaticMarkup } from "react-dom/server";
+import ProjectsPage from "../src/app/projects/page.js";
+import { importProjectTransferAsNew } from "../src/frontend/utils/api.js";
+import { importProjectTransferAsNewSchema } from "../src/shared/validation/project-transfer.schemas.js";
+
+describe("project overview import", () => {
+  it("renders a dedicated import-as-new-project entry point", () => {
+    const globalWithReact = globalThis as typeof globalThis & {
+      React?: typeof React;
+    };
+    const originalReact = globalWithReact.React;
+    globalWithReact.React = React;
+    let markup: string;
+    try {
+      markup = renderToStaticMarkup(React.createElement(ProjectsPage));
+    } finally {
+      globalWithReact.React = originalReact;
+    }
+
+    assert.match(markup, /Projekt importieren/);
+    assert.match(markup, /Projektdatei auswählen/);
+    assert.match(markup, /Als neues Projekt importieren/);
+    assert.doesNotMatch(markup, /Dieses Projekt ersetzen/);
+  });
+
+  it("uses the collection import endpoint without a target project id", async () => {
+    const requests: Array<{
+      url: string;
+      method: string;
+      body: unknown;
+    }> = [];
+    const originalFetch = globalThis.fetch;
+    globalThis.fetch = async (input, init) => {
+      requests.push({
+        url: String(input),
+        method: init?.method ?? "GET",
+        body: init?.body ? JSON.parse(String(init.body)) : null,
+      });
+      return new Response(
+        JSON.stringify({ projectId: "project-copy", name: "Projekt (Kopie)" }),
+        {
+          status: 201,
+          headers: { "Content-Type": "application/json" },
+        }
+      );
+    };
+
+    try {
+      const transfer = { format: "test" };
+      const result = await importProjectTransferAsNew(transfer);
+      assert.deepEqual(result, {
+        projectId: "project-copy",
+        name: "Projekt (Kopie)",
+      });
+      assert.deepEqual(requests, [
+        {
+          url: "/api/projects/import",
+          method: "POST",
+          body: { transfer },
+        },
+      ]);
+    } finally {
+      globalThis.fetch = originalFetch;
+    }
+  });
+
+  it("accepts only the strict transfer wrapper", () => {
+    assert.equal(
+      importProjectTransferAsNewSchema.safeParse({ transfer: {} }).success,
+      true
+    );
+    assert.equal(importProjectTransferAsNewSchema.safeParse({}).success, false);
+    assert.equal(
+      importProjectTransferAsNewSchema.safeParse({
+        transfer: {},
+        mode: "replace",
+      }).success,
+      false
+    );
+  });
+});