PROTECTIVE CIRCUIT FOR PROTECTING ELECTRIC MAINS SUPPLYING POWER TO UNDERWATER EQUIPMENT

摘要

Protection circuit for an electric grid supplying power to underwater devices by means of a multi-wire underwater cable, containing an insulating transformer and cut-out switch, characterized in that it has a leakage conductance relay (2) and differential relay (4), the input circuits of these relays being connected to the secondary winding of the insulating transformer (1), while the knock-out coil (5) of the differential relay is connected to the output circuits of the leakage conductance relay (2) and differential relay (4), these output circuits being connected in parallel.IMAGE