Distributed control device and distributed control system

A distributed control system comprising:

• a power supply terminal to which a commercial power supply is input and that outputs a first power supply voltage;
• a relay terminal electrically coupled to the power supply terminal;
• and
• a sub-terminal to which the first power supply voltage is supplied via the relay terminal, wherein
• the power supply terminal includes
• a first power supply circuit to which the commercial power supply is input and that outputs the first power supply voltage, and
• a power failure detection circuit that detects a voltage value of the commercial power supply and outputs a power failure notification signal corresponding to whether or not the detected voltage value is lower than a predetermined threshold value,
• the sub-terminal includes
• a first drive power supply circuit to which the first power supply voltage is supplied and that outputs a first drive voltage,
• a second drive power supply circuit to which the first power supply voltage is supplied and that outputs a second drive voltage,
• a control circuit operated by using the first drive voltage as a drive source, and
• a first drive device operated by using the second drive voltage as a drive source under control of the control circuit,
• the relay terminal includes a first switching circuit that switches whether or not to supply the first power supply voltage to the second drive power supply circuit,
• the first power supply voltage supplied to the first drive power supply circuit propagates through a first propagation path,
• the first power supply voltage supplied to the second drive power supply circuit is branched from the first propagation path and propagates through a second propagation path,
• the first switching circuit is provided in the second propagation path,
• the power failure detection circuit detects a voltage value of the commercial power supply, and outputs the power failure notification signal including power failure information indicating that the commercial power supply is abnormal, when the detected voltage value is lower than the predetermined threshold value, and
• the first switching circuit stops supply of the first power supply voltage to the second drive power supply circuit in accordance with a first switching control signal based on the power failure notification signal including the power failure information.