Abstract: A three-phase motor system is described incorporating a small fractional horsepower three-phase control motor that is connected to rotate in a predetermined direction when a three-phase drive motor is rotating in a predetermined direction. A plurality of microswitches having actuating arms with cam follower portions are mounted with the arms contacting a cam plate. When the system is energized, the cam plate is rotated to open the microswitches if the rotation of the fractional horsepower motor is reversed. The microswitches, when opened, de-energize the fractional horsepower motor and concurrently prevent the closure of a solenoid-operated start switch to prevent energization of the drive motor.