| 摘要 |
PURPOSE:To prevent the functions of a system from stopping owing to a fault occurring on a call signal line from a monitoring station to a station to be monitored by providing both stations with characteristic timers, and controlling the transmission of information from the station to be monitored through those timers. CONSTITUTION:Stations 2, 3, 4, and (n) to be monitored send monitor signals to a monitoring station 1, respectively, and the monitoring station 1 detects them to acquire pieces of information from the stations to be monitored, and also sends out a timer correcting signal to those stations to be monitored to correct timers equipped to the stations 2, 3, 4, and (n) to be monitored. Namely, the characteristic timer 6 of each station controls a switch 7 for a timer correcting signal and a monitoring signal for the station to be monitored to transmit those signals at specified time, and an alarm generation detector 8 controls a power supply controller 9; only when an alarm is generated at a station to be monitored, a monitor signal sending circuit 10 is powered on and in normal operation wherein no alarm is generated, the circuit is disconnected from the power source, thus reducing power consumption. |
