What is the difference between 2-pole, 4-pole, and 6-pole motors?

Last Updated: 1 week ago

To wire a 3-phase motor, you must choose between Star or Delta based on your supply voltage and motor nameplate.

Star (High Voltage): Links W2-U2-V2 together. Use this for 400V mains on a standard 230/400V motor.
Delta (Low Voltage): Links U1-W2, V1-U2, W1-V2 in pairs. Use this for 230V inverter supply on a standard motor.

  • Star (Y) Connection: Connects the three "finish" ends (W2, U2, V2) together. Used for 400V Supply on standard small/medium motors (up to 4.0kW).
  • Delta (Δ) Connection: Connects the start of one phase to the end of the next (U1-W2, V1-U2, W1-V2). Used for 230V Supply (e.g., Single Phase Inverter) on small motors, OR 400V Supply on large motors (4kW+) marked 400/690V.

Star Connection - Wiring Diagram

Three-phase motor star connection terminal box wiring diagram showing W2-U2-V2 linked together

Delta Connection - Wiring Diagram

Three-phase motor delta connection wiring diagram showing U1-W2, V1-U2, W1-V2 linked positions

** STOP: Check your motor nameplate.

  • If it says 230/400V: Star = 400V (Mains), Delta = 230V (Inverter).
  • If it says 400/690V: Delta = 400V (Mains), Star = 690V.