Protective relay for polyphase electrical apparatus

Claim 1

AN AUTOMATIC PROTECTIVE DEVICE FOR A POLYPHASE LOAD HAVING MORE THAN TWO POWER LINES CONNECTED THERETO COMPRISING, TRANSFORMER MEANS OPERATIVELY INTERCONNECTING DIFFERENT PAIRS OF THE POWER LINES FOR INDUCING INVERTED CURRENTS REPRESENTING THE SAME POWER FUNCTION ASSOCIATED WITH THE RESPECTIVE POWER FUNCTION ASSOCIATED TIVELY CONNECTED TO THE TRANSFORMER MEAS TO SHIFT SAID INDUCED CURRENTS INTO PHASE OPPOSITION UNDER NORMAL POLYPHASE OPERATION OF THE LOAD, BALANCE CONTROL MEANS OPERATIVELY CONNECTED TO THE PHASE SHIFT MEANS FOR COMBINING SAID PHASE SHIFTED INDUCED CURRENTS INTO A RESULTANT CURRENT APPROACHING ZERO UNDER NORMAL OPERATING CONDITIONS, RECTIFIER AND FILTER MEANS OPERATIVELY CONNECTED TO THE BALANCE CONTROL MEANS FOR CONVERTING ANY EXCESSIVE RESULTANT CURRENT INTO AN ENERGIZING CURRENT, REALY MEANS OPERATIVELY CONNECTED TO SAID RCTIFIER AND FILTER MEANS FOR ENERGIZATION BY AN ENERGIZING CURRENT THEREFORM, CONTROL CIRCUIT MEANS RNDERED OPERATIVE IN RESPONSE TO ENERGIZATION OF SAID RELAY MEANS AND CIRCUIT BREAKER MEANS OPERATIVELY CONNECTED TO SAID POWER LINES AND CONTROLLED BY THE CONTROL CIRCUIT MEANS FOR DISCONNECTING THE POWER LINES WHEN THE CONTROL CIRCUIT MEANS IS RENDERED OPERATIVE