A run capacitor is wired across the auxiliary and main
windings of a single phase permanent split capacitor motor.
The capacitors primary function is to reduce the line current
while greatly improving the torque characteristics of a motor.
This is accomplished by using the 90° phase relationship
between the capacitor current and voltage in conjunction with
the motor windings, so that the motor will give two phase
operation when connected to a single phase circuit. The
capacitor also reduces the line current to the motor by
improving the power factor.