| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to reduce the labor of wiring or construction by connecting optical alarm units onto a sensor line drawn out of a receiver without causing a problem such as an alarm malfunction on a non-alarm line or unsuccessful driving of optical alarm on an alarm line.SOLUTION: A fire receiver 10 is provided with a line voltage control unit 32. If a fire alarm of a fire sensor 14 is detected, a predetermined high-voltage pulse having a predetermined pulse duration is convoluted to a predetermined line supply voltage, which is fed to sensor lines 12-1 to 12-n, at intervals of a predetermined light-emission cycle. Optical alarm units 18 connected together with the fire sensors 14 onto the sensor line drawn out of the fire receiver 10 input the high-voltage pulse convoluted by an optical alarm control unit, and control light emitters to emit light so as to flicker concurrently in identical cycles.SELECTED DRAWING: Figure 1 |
