All the 3 Phase motors operate at their best when the power supply in all the 3 phases are continuous. Failing of any one of the phases is termed as single phasing. During single phasing, the motors draw more current than the rated value which results in burning of the motor coils. Single Phase Preventer is a product which provides a solution to this problem by sensing the single phase condition and instantaneously turning off the power supply to the motor thereby protecting the motor from drawing excess current. Single Phase Preventors are incorporated in the 3 Phase starters.