Ground cable continuity check circuit

Claim 1

IN A GROUND CABLE CONTINUITY CHECK CIRCUIT FOR A POWER SUPPLY CABLE HAVING A GROUNDING CONDUCTOR AND AN ADDITIONAL PILOT CONDUCTOR FOR USE IN ESTABLISHING THE CONTINUITY OF THE GROUNDING CONDUCTOR AND HAVING THE ENDS OF THE GROUNDING CONDUCTOR AND THE ADDITIONAL PILOT CONDUCTOR REMOTE FROM THE POWER SUPPLY ELECTRICALLY INTERCONNECTED SO AS TO FORM A CLOSED CONDUCTIVE LOOP, THE COMBINATION COMPRISING CIRCUIT BREAKER MEANS CONNECTED IN CIRCUIT RELATIONSHIP WITH THE POWER SUPPLY CABLE FOR INTERRUPTING CURRENT FLOW THERETHROUGH, MEANS FOR IMPRESSING A CIRCULATING DIRECT CURRENT THROUGH THE GROUNDING CONDUCTOR LOOP, BRIDGE CIRCUIT MEANS FOR COMPARING THE VALUE OF THE CIRCULATING DIRECT CURRENT IN THE GROUND CONDUCTOR LOOP TO A REFERENCE VALUE AND FOR DERIVING AN OUTPUT ERROR SIGNAL INDICATIVE OF ANY DECREASE IN THE GROUND CONDUCTOR LOOP, AND MEANS FOR COUPLING THE ERROR SIGNAL THUS DERIVED BACK TO THE CIRCUIT BREAKER MEANS FOR INTERRUPTING POWER FLOW THROUGH THE POWER SUPPLY CABLE IN RESPONSE TO A DECREASE IN THE VALUE OF THE DIRECT CURRENT CIRCULATING THROUGH THE GROUND CONDUCTOR LOOP.