GAS LEAKAGE ALARM UNIT WITH FIRE ALARM FUNCTION

摘要

PROBLEM TO BE SOLVED: To prevent a fire which occurs in an alarm unit by interrupting the supply of an AC power source to a power source circuit when atmosphere temp. detected by means of a temp. detecting circuit exceeds a previously fixed self fire alarm value.;SOLUTION: A power source interrupting circuit 7 as a power source interrupting means is arranged between the primary side of a transformer 1a and a commercial AC power source AC. The circuit 7 is provided with a thyristor th connected to the primary side coil of the transformer 1a in parallel and a fuse H serially connected to the coil. Then the gate of the thyristor is connected to a microcomputer 5 and the microcomputer 5 outputs a power source interrupting signal S4 to the gate of the thyristor th in the case of detecting the occurrence of self fire and interrupts the supply of the AC power source to a power source supply circuit 1. Thus, the fire to occur in the alarm unit is prevented.;COPYRIGHT: (C)2001,JPO