Abstract: A control device for industrial machines includes a plurality of signal input-output circuits configured such that pulse widths of pulse signals output from the signal input-output circuits are different from each other. The control device detects a fault when a pulse signal output from one of the signal input-output circuits has a pulse width different from the pulse width set to the one of the signal input-output circuits.

Abstract: A relay fault diagnosis device includes: at least one C-contact relay that has a common terminal, a normally open terminal and a normally closed terminal; a read-back circuit that is connected to the normally closed terminal of the relay; and a diagnostic section that outputs a test signal to the common terminal to diagnose a fault in the relay.

Abstract: An output module for a PLC includes an output circuit. This output circuit is open or closed selectively between a power supply terminal (to which a power supply voltage is supplied) and an output terminal (connected to a solenoid). The output module includes a control apparatus which controls the operation of the output circuit. The output circuit includes switches connected in series to each other between the power supply terminal and the output terminal, and a current output section which performs an operation of short-circuiting terminals of the switch to pass a predetermined current through a path formed due to the short-circuiting. The control apparatus includes on/off control sections which controls on/off states of the respective switches, and diagnosis sections which perform a diagnosis on presence of a short-circuit fault in the respective switches based on diagnostic signals output from a low-potential terminal of the switches.

Abstract: The present disclosure describes a failure diagnosis circuit may comprise a first terminal, a second terminal, a first relay and a second relay, a diagnostic signal transmission circuit, a transmission circuit diagnosis circuit, a first diagnostic signal reception circuit, a first reception circuit diagnosis circuit, a second diagnostic signal reception circuit, a second reception circuit diagnosis circuit, and a controller.

Abstract: An output module for a PLC includes an output circuit. This output circuit is open or closed selectively between a power supply terminal (to which a power supply voltage is supplied) and an output terminal (connected to a solenoid). The output module includes a control apparatus which controls the operation of the output circuit. The output circuit includes switches connected in series to each other between the power supply terminal and the output terminal, and a current output section which performs an operation of short-circuiting terminals of the switch to pass a predetermined current through a path formed due to the short-circuiting. The control apparatus includes on/off control sections which controls on/off states of the respective switches, and diagnosis sections which perform a diagnosis on presence of a short-circuit fault in the respective switches based on diagnostic signals output from a low-potential terminal of the switches.

Abstract: A control device for industrial machines includes a plurality of signal input-output circuits configured such that pulse widths of pulse signals output from the signal input-output circuits are different from each other. The control device detects a fault when a pulse signal output from one of the signal input-output circuits has a pulse width different from the pulse width set to the one of the signal input-output circuits.

Abstract: The present disclosure describes a failure diagnosis circuit may comprise a first terminal, a second terminal, a first relay and a second relay, a diagnostic signal transmission circuit, a transmission circuit diagnosis circuit, a first diagnostic signal reception circuit, a first reception circuit diagnosis circuit, a second diagnostic signal reception circuit, a second reception circuit diagnosis circuit, and a controller.

Abstract: A relay fault diagnosis device includes: at least one C-contact relay that has a common terminal, a normally open terminal and a normally closed terminal; a read-back circuit that is connected to the normally closed terminal of the relay; and a diagnostic section that outputs a test signal to the common terminal to diagnose a fault in the relay.