SHORT-CIRCUIT AND PHASE LOSS PROTECTIVE DEVICE FOR ELECTRIC MOTOR AND ITS POWER SUPPLY CABLE Russian patent published in 2015 - IPC H02H7/08 H02H7/85 H02H7/93 

FIELD: electricity.

SUBSTANCE: short-circuit and phase loss protective device for electric motor and its power supply cable comprises nine identical units with magnetically operated element, which are mounted close to current-conducting wires of A, B, C phases from the side of electric motor input; nine identical units with magnetically operated element are mounted close to current-conducting wires of A, B, C phases from the side of the motor zero leads; three identical units with magnetically operated element are mounted close to current-conducting wire of one phase from the side of electric motor input; three identical fault-identifying units are connected respectively to three units with magnetically operated element mounted from the side of electric motor input and to three units with magnetically operated element mounted from the side of the motor zero leads; six OR elements; TIME elements and NOT elements. Aforesaid units and elements are interconnected in such a way as pointed out in application materials.

EFFECT: improved reliability and sensitivity to turn-to-turn short-circuits.

7 dwg