Supervised annunciator

Claim 1

IN A DETECTION SYSTEM, AT LEAST ONE NORMALLY OPEN DEVICE PROVIDING A CLOSED CIRCUIT UPON THE PRESENCE OF A PREDETERMINED CONDITION, A SOURCE OF POWER, A FIRST AND A SECOND LOOP CIRCUIT, MEANS CONNECTING ONE END OF EACH OF SAID LOOPS TO AN OPPOSITE SIDE OF SAID SOURCE, MEANS CONNECTING SAID DEVICE BETWEEN SAID LOOPS, A FIRST RELAY MEANS HAVING A FIRST ENERGIZATION WINDING, SECOND RELAY MEANS HAVING A HOLDING CIRCUIT, FIRST CIRCUIT MEANS ASSOCIATED WITH SAID SECOND RELAY MEANS FOR CONNECTING SAID FIRST ENERGIZATION WINDING BETWEEN SAID LOOPS TO ESTABLISH A SUPERVISORY CIRCUIT WHEREBY SAID FIRST RELAYS MEANS IN ENERGIZED IF NO TROUBLE EXITS IN SAID CIRCUIT TO AFFECT THE SUPPLY OF A PREDETERMINED CURRENT TO SAID ENERGIZATION WINDING, MEANS ASSOCIATED WITH SAID FIRST RELAY MEANS IS ENERGIZED FOR CONNECTING SAID SECOND RELAY MEANS TO SAID SOURCE TO INDICATE THE PRESENCE OF TROUBLE IN THE SYSTEM, MEANS ASSOCIATED WITH SAID SECOND RELAY MEANS FOR CONNECTING SAID SOURCE TO SAID LOOPS AT THE OPPOSITE ENDS FROM SAID FIRST MENTIONED POWER CONNECTION WHEN SAID PREDETERMINED CURRENT DOES NOT EXIST WHEREBY SAID FIRST RELAY MEANS CAN BE ENERGIZED UPON A CLOSED CIRCUIT OF SAID DEVICE EVEN THOUGH SAID OPEN CIRCUIT TROUBLE IS PRESENT, AND CYCLING MEANS OPERABLE DURING SAID TROUBLE FOR PERIODICALLY DEENERGIZING SAID SECOND RELAY MEANS TO ESTABLISH SAID SUPERVISORY CIRCUIT TO CHECK SAID CIRCUIT SO THAT IF SAID TROUBLE IS GONE SAID SECOND RELAY WILL REMAIN DEENERGIZED.