soft starting single phase motor

Author	Message
phil99 Guru Joined: 11/02/2018 Location: Australia Posts: 3273	Posted: 07:07am 19 Mar 2026       If the soft-starter is a 2 wire type it is best to wire it in series with the motor main winding only. You want full volts across the start winding and its series capacitor to get enough phase shift for the required starting torque. The capacitor limits the start current in that winding to little more than its normal running current. If the soft-starter is only wired in the supply to the motor there may not be enough starting torque to turn it at all.