Automatic Phase Selector Controllers

The Universal Automatic Electronic Phase Switch (single-phase automatic throw-over breaker) is designed to supply an industrial/ appliance single phase 220V/50Hz load from three phase four wire mains 3 x 380 + N in order to maintain uninterrupted power supply of essential single-phase loads and protect them against un-allowable voltage variations in the mains. For this purpose, a single-phase load is switched into a three phase circuit. Depending on voltage presence and voltage quality on phases the PEF-301 will automatically select the optimum phase and promptly switch the single phase load supply to this phase. A phase prioritization is foreseen, i.e. the device restores the supply circuit to the user-selected priority phase after switching to reserve phases and regenerating the voltage on the priority phase.