Contactors are the workhorse of motor control centers. Selection starts with utilization category (typically AC-3 for squirrel-cage motors) and the motor’s full-load current.

Coil voltage must match the control circuit—24 VDC, 110 VAC, or 230 VAC are common. Confirm inrush and holding power against the control transformer VA rating.

Pair the contactor with a correctly set overload relay, verify mechanical interlocking for reversing starters, and leave spare auxiliary contacts for PLC feedback.