Abstract: A speed sensitive, load sensitive and AC line voltage fluctuation insensitive, motor starting system is provided for an AC motor having a main winding (1) and an auxiliary winding (2) both connectable across an AC power source (3). Relative magnitudes of main and auxiliary winding voltages are sensed and compared. The auxiliary winding is disconnected (5) from the AC source when the auxiliary winding voltage, including the components from the AC source and from rotationally induced voltage, rises above a predetermined value relative to the main winding voltage as a function of motor speed. After starting, when the motor is in a run mode and the auxiliary winding is disconnected from the AC source, only the rotationally induced auxiliary winding voltage is sensed.