What is a 9-lead AC motor?

• A. A dual-voltage motor with 9 leads brought out; three coils with center taps, for wye or delta at two voltages.
• B. A motor with nine stator poles.
• C. A single-voltage motor with nine windings in series.
• D. A motor designed for 90V operation.

Answer: (A)

Nine-lead motors are dual‑voltage machines that have three windings, each with a center tap, brought out as separate leads. That gives nine leads total. The center taps let you reconfigure the windings for two different line voltages and for different connection schemes, typically enabling a wye (star) or delta connection. At the lower voltage the windings can be wired in parallel so each coil sees the same voltage; at the higher voltage they are wired in series so the voltage adds across the windings. This combination of center taps and multiple leads is what defines a 9‑lead motor as dual‑voltage with windings that can be connected for two voltages and either wye or delta.