| 摘要 |
<p>A transmitter (T) for use with a fire alarm system controls the monitoring of a device (B) to be controlled based on a control command transmitted from a receiving section (RE) such as a fire receiver. With this transmitter, even if there is a short circuit in control lines (CL) for connecting the transmitter and the device (B), it is not necessary to exchange fuses, and it is also possible to avoid the waste of power consumption which would otherwise incur during the actuation operation of the devices. When the short circuit is recovered, the transmitter is able to correctly actuate the device. A small reverse current is permitted to flow in the control lines so as to enable the monitoring of a short circuit in the control lines by the transmitter. When the transmitter receives an actuation command from the receiving section, and if a short circuit in the control lines is detected, the transmitter goes into a standby state in which it holds an actuation signal from being output to an actuating section. When the short circuit is recovered, the transmitter outputs the actuation signal to the actuating section. <IMAGE></p> |
