Equipment operation check system for transmission lines

摘要

In a transmission line to which a large number of devices are connected, the presence or absence of device malfunction due to a voltage drop in the transmission line is checked, and the power supply voltage is switched in two stages. A master station that transmits control signals for a plurality of control target devices and a plurality of slave stations connected to each of the plurality of control target devices are connected to a transmission line for control signals. In the slave station, the first operation is performed when the current value of the current or voltage of the control target device is a first operation failure state that is smaller than a first threshold value that is a current or voltage value required for the ON operation of the control target device. When a failure signal is output and is smaller than a second threshold value that is a current or voltage value necessary for the ON operation holding state, the second operation failure signal is output. In addition, the slave station recovers the power supply voltage obtained from the transmission line with less power consumption than the first voltage necessary for the ON operation of the control target device or the first voltage necessary and sufficient for the ON operation holding state. Output as a second voltage higher than the voltage.