Template · Commercial and industrial

Motor control centre single line diagram

MCC with starters, a drive, a lighting transformer and a spare bucket. Use this for a motor control centre in a plant or mechanical room: a line-up of starters, a drive, a lighting transformer and a spare bucket.

A free template with typical ratings, conductor callouts and general notes. Open it, change what differs on your job, fill in the title block and export a PDF.

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Motor control centre single line diagram: MCC with starters, a drive, a lighting transformer and a spare bucket. — Motor control centre. 16 devices on an 11 × 17 in sheet with a title block and notes column.

What the reviewer checks on this drawing

The reviewer checks motor circuit protector settings and overloads taken from nameplate data, a nameplate on every bucket, and a disconnect within sight of each motor, or a lockable one where that is permitted.

What the drawing shows

Every device on the sheet, in the order power reaches it.

Symbol	Label	Rating or detail	Conductors feeding it
Device	Main distribution (MDP)	600V 3φ 3W
Circuit breaker	400A 3P	MCC feeder
Panel	MCC-1	600A horizontal bus · 600V 3φ	3 × 500 kcmil Cu, + #3 G
Circuit breaker	30A MCP	Bucket 1A
Motor starter	FVNR size 1	Overload relay
Motor	P-101	10 HP · feed pump
Circuit breaker	50A MCP	Bucket 1B
Device	Variable frequency drive (VFD)	25 HP
Motor	AHU-1	25 HP · supply fan
Circuit breaker	15A MCP	Bucket 2A
Motor starter	FVNR size 1	Overload relay
Motor	CP-1	5 HP · conveyor
Circuit breaker	40A 3P	Bucket 2B
Transformer	Transformer	30 kVA, 600V – 120/208V
Panelboard	Panel LP-MCC	100A
Circuit breaker	Spare	Bucket 3A

Notes on the sheet

Motor circuit protector settings and overload heaters selected from motor nameplate data.
Each bucket identified with an engraved nameplate showing the equipment tag and load served.
Local disconnect within sight of each motor, or lockable bucket disconnect where permitted.

Diagram is schematic and not to scale. Field-verify existing equipment ratings. Ratings and conductor sizes shown are typical. Confirm against the adopted code, the equipment listing and a load calculation before installation. Code references are to the 2023 NEC and the 2024 Canadian Electrical Code: see references and editions.