| 摘要 |
PURPOSE:To reduce the power consumption and at the same time to improve the reliability with check of faults, etc. for a switching system of a device in current use to spare one, by supplying usually no power to a spare device but supplying the power periodically and in a short time to the spare device to confirm an alarm. CONSTITUTION:When an alarm signal (a) is transmitted from a transmitter/ receiver 1, a control signal (g) is transmitted from a control part 6 to actuate a power supply 4. Then a transmitter/receiver 2 is actuated. At the same time, an alarm signal (b) is checked at the part 6. If no signal (b) is delivered, a control signal (c) is transmitted to switch a switching part 5. Thus the transmitter/ receiver 2 is selected. In this case, no control signal (f) is delivered to give no actuation to the power supply 3. Therefore no power is supplied to the transmitter/receiver 1. While the signal (f) is sent every fixed period of time to the power supply 3 under no actuation from the part 6. Then the power is supplied in a short time to the non-selected transmitter/receiver 1 to check the output of the signal (a). |
