{"schemaVersion":1,"slug":"iec-distribution-board-plan-mark","name":"Distribution board plan mark","kind":"symbol","abbreviation":"DB","aliases":["distribution board location symbol","consumer unit plan mark","sub-board plan symbol"],"category":"installation-communications","drawingTypes":["GA"],"referenceFamilies":["IEC"],"summary":"Plan mark showing the position of a distribution board or consumer unit on an installation layout.","description":["On installation plans a distribution board is drawn as a rectangle against the wall, typically half filled or crossed, with its designation such as DB-1 written beside it. Home-run arrows from outlets and lights terminate in labels that refer back to this board.","The mark tells the reader where circuits originate and where the board schedule applies. In domestic work the same form is used for a consumer unit, often labelled CU. Clearance in front of the board and access requirements should be checked against the architectural plan.","The plan mark does not show the internal arrangement. The board schedule and single-line diagram show incoming supply, protective devices and circuits."],"readingNotes":["Read the designation and look up the board schedule.","Check clearances and mounting height."],"drawingChecklist":["Label the board designation.","Reference the board schedule.","Show clear working space."],"distinction":"A switchboard object on a GA shows a physical lineup; the plan mark only locates a board on a building plan.","facts":[{"label":"Graphic form","value":"Rectangle on the wall, partly filled or crossed"},{"label":"Companion document","value":"Board schedule"},{"label":"Exact standard graphic","value":"Not reproduced here; confirm the form against IEC 60617 and the project legend"}],"references":[{"sourceId":"iec-diagrams","relevance":"IEC graphical symbol context; independently drawn here."},{"sourceId":"pub-object-engineering-design","relevance":"Installation design methodology: circuits are allocated to boards."}],"related":["switchboard","ansi-panelboard-plan-symbol","miniature-circuit-breaker"],"artwork":"s28-iec-distribution-board-plan-mark","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","symbolVariant":{"convention":"IEC","form":"Distribution board, installation plan","reference":"IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier."},"plainEnglish":{"title":"What does Distribution board plan mark mean?","introduction":"On installation plans a distribution board is drawn as a rectangle against the wall, typically half filled or crossed, with its designation such as DB-1 written beside it. Home-run arrows from outlets and lights terminate in labels that refer back to this board.","example":"The mark tells the reader where circuits originate and where the board schedule applies. In domestic work the same form is used for a consumer unit, often labelled CU. Clearance in front of the board and access requirements should be checked against the architectural plan.","drawings":"The plan mark does not show the internal arrangement. The board schedule and single-line diagram show incoming supply, protective devices and circuits.","terms":[{"name":"Schematic","meaning":"A drawing showing function and connections rather than physical appearance."}],"diagram":"flow","steps":["Identify the device and form","Read the connections and state","Check the equipment reference"],"caption":"A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.","sources":[{"label":"IEC graphical symbols for diagrams","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/"},{"label":"Electrical installation design methodology and references","url":"https://www.electrical-installation.org/enwiki/General_rules_of_electrical_installation_design"}],"detail":"Plan mark showing the position of a distribution board or consumer unit on an installation layout. A switchboard object on a general arrangement shows a physical lineup; the plan mark only locates a board on a building plan.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/iec-distribution-board-plan-mark","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/iec-distribution-board-plan-mark.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"iec-diagrams","title":"IEC graphical symbols for diagrams","publisher":"IEC","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/","type":"standard","scope":"IEC 60617 and related symbol-design publications. Full database access requires a subscription.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"IEC graphical symbol context; independently drawn here."},{"id":"pub-object-engineering-design","title":"Electrical installation design methodology and references","publisher":"Schneider Electric — Electrical Installation Guide","url":"https://www.electrical-installation.org/enwiki/General_rules_of_electrical_installation_design","type":"manufacturer","scope":"Public design context. No universal working clearance, equipment dimension or project compliance conclusion is asserted.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Installation design methodology: circuits are allocated to boards."}]}