Designed for automatic reduced voltage starting of squirrel cage motors, the autotransformer type starter provides the highest starting torque per ampere of line current, and is thus an effective means of motor starting for applications where the inrush current must be reduced with a minimum sacrifice of starting torque.

Starter components include: Three 3-pole contactors, designated in the wiring diagram as START, NEUTRAL, and RUN; a 3-phase starting autotransformer; an adjustable pneumatic timer; and are available with eutectic alloy overload relay as well as Smart Motor Protectors (SMP) solid-state overload relay, either a fusible disconnect switch or a circuit breaker, a HAND-OFF-AUTO selector switch, and a START button.

• UL 508
• CSA 22.2 No. 14