How is a 9-lead motor connected for low voltage (example 230 V)?

How is a 9-lead motor connected for low voltage (example 230 V)?

• A. Connect leads 1, 2, 3 to power; connect leads 7, 8, 9 insulated separately; 4, 5, 6 tied.
• B. Connect leads 1, 2, 3 to power; connect 4-9 together; 7-9 insulated.
• C. Connect leads 1, 2, 3 to power; connect leads 4, 5, 6 together (neutral); 7, 8, 9 insulated separately.
• D. Connect 1-3 to power; leave 4-9 insulated.

Answer: (C)

A nine-lead motor with three windings that each have a center tap is wired in a star (wye) configuration for low voltage. Tie the three center-tap leads together to form a neutral point, and connect each outer end to one of the three supply lines. The remaining three leads are left insulated because they’re not used in this wiring scheme. In this setup each winding is energized from a line to neutral, providing balanced voltages and symmetrical torque across the three phases. The other wiring options would either short windings, fail to provide a common neutral, or leave windings unenergized, which wouldn’t deliver the correct voltage distribution or safe operation.

A nine-lead motor with three windings that each have a center tap is wired in a star (wye) configuration for low voltage. Tie the three center-tap leads together to form a neutral point, and connect each outer end to one of the three supply lines. The remaining three leads are left insulated because they’re not used in this wiring scheme. In this setup each winding is energized from a line to neutral, providing balanced voltages and symmetrical torque across the three phases. The other wiring options would either short windings, fail to provide a common neutral, or leave windings unenergized, which wouldn’t deliver the correct voltage distribution or safe operation.