How is a 12-lead motor connected for high voltage wye (example 460 V)?

• A. Connect power to leads 1, 2, 3; connect neutral to 4, 5, 6; connect groups 7&10, 8&11, 9&12 as separate groups, with only one group energized.
• B. Connect power to leads 7, 10; 8, 11; 9, 12 and leave 1-3 unconnected.
• C. Tie 7-10, 8-11, 9-12 together and connect to L1, L2, L3.
• D. Connect 1-3 in delta and energize.

Answer: (A)

High voltage operation of a 12‑lead motor is achieved by putting the windings for each phase in series and forming a neutral point. In this wiring, the lines go to the designated line ends and the other ends are tied together to create the star point. By applying the line voltage to leads 1, 2, and 3 and tying 4, 5, and 6 together as the neutral, you establish the three phases. The remaining leads are paired so each phase is made from two windings in series: 7 pairs with 10, 8 with 11, and 9 with 12. This arrangement puts the windings in series for the high voltage (460 V) operation while maintaining a common neutral reference. The practical idea is that each phase is formed by two windings in series, fed by its own line, with the neutral point created by tying the designated ends. Other schemes would either parallel windings or connect delta, which aren’t suitable for the high-voltage star configuration.