MOTORS · REFERENCE GUIDE
3-phase motor wiring (6 terminals)
Reference guide to 3-phase motor wiring (6 terminals): 3 checks to work through, the limits that apply and when to verify against the NEC and maker data.
US (NEC) only · NFPA 70 / NEC — locally adopted editionDefaults are US values. Verify the locally adopted NEC edition and project data.Official reference ↗
REFERENCE GUIDE
Before starting
- IEC U1/V1/W1 and U2/V2/W2 labels are a convention, not proof of actual lead arrangement.
- For a motor explicitly approved by its nameplate: star joins winding ends; delta connects each start to the next winding end.
- Physical bridge positions vary. Follow the actual terminal-box diagram and nameplate voltage.
This is a reference guide, not a sizing calculator or installation approval.
Method & assumptions
Reference workflow — project-specific verified data required
This is a reference guide, not a sizing calculator or installation approval.
Results do not check every aspect of an electrical installation. The calculators follow US (NEC) practice only; a regional preset changes defaults such as voltage and units, and no result certifies NEC compliance.
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