Polyphase protective relay circuits

Claim 1

A PROTECTIVE CIRCUIT ARRANGEMENT RESPONSIVE TO FAULTS OCCURRING IN A SELECTED SECTION OF A POLYPHASE SUPPLY LINE COMPRISING, TWO RELAY CIRCUITS COUPLED TO THE LINE CONDUCTORS AT OPPOSITE ENDS OF THE SAID SELECTED SECTION, EACH RELAY CIRCUIT COMPRISING A PLURALITY OF INPUT CIRCUIT MEANS SEPARATELY COUPLED TO SELECTED CONDUCTORS IN THE LINE FOR DEVELOPING SIGNALS PROPORTIONAL TO THE CURRENT IN THESE CONDUCTORS, A LIKE PLURALITY OF RECTIFYING NETWORKS EACH COMPRISING A BRIDGE RECTIFIER HAVING A.C. TERMINALS CONNECTED TO SAID INPUT CIRCUIT MEANS D.C. TERMINALS AND A SMOOTHING CIRCUIT CONNECTED TO SAID D.C. TERMINALS, CONNECTING MEANS FOR CONNECTING TOGETHER THE D.C. OUTPUTS OF ALL THE RECTIFYING NETWORKS, AND RESISTOR MEANS CONNECTED IN SERIES WITH SAID CONNECTING MEANS, THE D.C. OUTPUTS OF ALL THE RECTIFYING NETWORKS BEING CONNECTED TOGETHER IN LIKE MANNER BY SAID CONNECTING MEANS WHEREBY THE D.C. TO WHICH SAID RESISTOR MEANS RESPONDS IS PROPORTIONAL TO ONLY THE LARGEST MEAN CURRENT TRAVERSING ANY ONE OF SAID NETWORKS DURING EACH CYCLE, PILOT WIRE MEANS CONNECTING TOGETHER THE RESISTOR MEANS ASSOCIATED WITH THE TWO RELAY CIRCUITS SO THAT THE VOLTAGES DEVELOPED THEREACROSS ARE IN OPPOSITION TO ONE ANOTHER, AND A PROTECTIVE DEVICE CONNECTED TO SAID PILOT WIRE MEANS AND RESPONSIVE TO ANY CURRENT FLOW THERETHROUGH.