Apparatus for testing portable equipment for a. c. and d. c. leakage and for ground continuity

Claim 1

AN ELECTRICAL TESTER FOR EQUIPMENT WHICH IS ENERGIZED THROUGH A POLARIZED PLUG AND A CABLE WITH ONE CONDUCTOR OF SAID CABLE CONNECTED TO THE METALLIC FRAME OF SUCH EQUIPMENT WHICH COMPRISES A METALLIC REFERENCE GROUND, A DOUBLE POLE-DOUBLE THROW SWITCH, CONDUCTOR MEANS FOR CONNECTING THE SWITCH POLES TO A POWER SOURCE AND SAID METALLIC REFERENCE GROUND TO AN EXTERNAL GROUND, A POLARIZED RECEPTACLE HAVING A PAIR OF POWER TERMINALS AND A GROUND TERMINAL WHICH MATE WITH SAID PLUG, SAID GROUND TERMINAL CONNECTED TO SAID REFERENCE GROUND, ELECTRICAL POWER CONDUCTORS CONNECTING ONE SET OF THE SWITCH CONTACTS TO SAID POWER TERMINALS, A TRANSFORMER HAVING ONE PRIMARY WINDING AND A HIGH CURRENT-LOW VOLTAGE SECONDARY AND A HIGH VOLTAGE-LOW CURRENT SECONDARY, SAID PRIMARY WINDING CONNECTED ACROSS THE OTHER SET OF SWITCH CONTACTS, A CURRENT RELAY HAVING A WINDING, A PAIR OF RECTIFIER CONTACTS AND A PAIR OF TEST CONTACTS, EACH OF SAID CONTACT PAIRS BEING NORMALLY OPEN, A GROUND CONTINUITY ELECTRICAL PATH INCLUDING IN SERIES THEREIN SAID GROUND TERMINAL, SAID CURRENT RELAY WINDING, SAID HIGH CURRENT SECONDARY, AN ELECTRICAL CURRENT LIMITING RESISTANCE, AND A GROUND CONTINUITY CONDUCTOR EXTENDING EXTERIOR OF SAID TESTER FOR CONNECTION TO SAID METALLIC FRAME, A DOUBLE POLE-SINGLE THROW SWITCH, HAVING TWO PAIRS OF CONTACTS WHEREBY WHEN SAID SINGLE THROW SWITCH IS CLOSED THE CONTACTS OF EACH PAIR ARE CONNECTED TO ONE ANOTHER, A SECOND RESISTOR CONNECTED BETWEEN ONE CONTACT OF EACH OF SAID PAIRS, AND ONE OF THE TERMINALS OF SAID SECOND RESISTOR CONNECTED TO SAID GROUND TERMINAL, A THIRD RESISTOR CONNECTED BETWEEN ONE OF SAID RECEPTACLE POWER TERMINALS AND ANOTHER CONTACT OF SAID SINGLE THROW SWITCH, THE REMAINING FREE CONTACT OF SAID SINGLE THROW SWITCH CONNECTED TO SAID RECEPTACLE GROUND TERMINAL, FULL WAVE RECTIFIER MEANS HAVING INPUT AND OUTPUT TERMINALS, SAID INPUT TERMINALS CONNECTED ACROSS SAID HIGH VOLTAGE SECONDARY, RECTIFIER CURRENT INDICATOR MEANS CONNECTED IN SERIES WITH ONE RECTIFIER OUTPUT TERMINAL AND SAID ONE OF SAID POWER TERMINALS AND SAID RECTIFIER CONTACTS OF SAID RELAY, THE OTHER RECTIFIER OUTPUT TERMINAL CONNECTED TO SAID REFERENCE GROUND, AN ELECTRICAL TEST PATH INCLUDING IN SERIES THEREIN SAID PRIMARY, VOLTAGE TEST INDICATOR MEANS AND SAID TEST RELAY CONTACTS.