Apparatus for non-destructive testing of enclosed relays for parasitic arc susceptibility by controlling the current-time integral of the arc

Claim 1

APPARATUS FOR CONTROLLING THE DURATION AND CURRENT INTENSITY OF AN ARC BETWEEN FIRST AND SECOND ELECTRICAL CONTACTS SO THAT SAID ARC IS EXTINGUISHED WHEN THE TIME INTEGRAL TO THE CURRENT OF SAID ARC REACHES A PREDETERMINED VALUE, COMPRISING A D.-C. CONSTANT-CURRENT SUPPLY CONNECTED IN SHUNT WITH SAID ELECTRICAL CONTACTS FOR ESTABLISHING AN ARC BETWEEN SAID ELECTRICAL CONTACTS UPON OPENING OF SAID CONTACTS, NORMALLY OPEN SWITCHING MEANS IN SHUNT CIRCUIT WITH SAID ELECTRICAL CONTACTS, MEANS RESPONSIVE TO THE VOLTAGE OF SAID ARC FOR PRODUCING A SIGNAL HAVING A VALUE DEPENDENT ON SAID VOLTAGE AND ON THE DURATION OF SAID ARC, SAID SIGNAL ATTAINING A GIVEN VALUE WHEN THE DURATION OF THE ARC IS SUCH THAT SAID TIME INTEGRAL ATTAINS SAID PREDETERMINED VALUE, AND MEANS RESPONSIVE TO SAID SIGNAL FOR CLOSING SAID SWITCHING MEANS WHEN SAID SIGNAL HAS SAID GIVEN VALUE, THEREBY TO SHORT CIRCUIT AND CONTACTS AND EXTINGUISH SAID ARC.