An apparatus and method for protecting an induction motor from momentary power loss in a three-phase, alternating current, power supply. The apparatus includes a circuit for detecting when the motor switches from a mode of operation as a motor to a mode of operation as a generator, and a microprocessor connected to the detector to receive the detection of a switch in mode of operation, and for generating a fault disconnect signal in response thereto to initiate disconnecting the motor from the power source. The method includes the steps of detecting when the motor switches from a mode of operation as a motor to a mode of operation as a generator and generating a fault disconnect signal in response thereto to initiate disconnecting the motor from the power source. The apparatus and method provide for robustness of the fault detection data, and for avoiding false detections of momentary power loss.
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