A retrofit switch actuator for a circuit breaker control switch in a power distribution network provides for remote control and automation of the control switch. A solenoid of the switch actuator is energized to move the output shaft of the solenoid. The movement of the solenoid output shaft is transferred by a connector mounted at one end to the solenoid output shaft and mounted at the other end to the control shaft of the circuit breaker to rotational movement of the control shaft. The motion of the control shaft mechanically engages the existing circuit breaker control switch.