JPH0383440U

JPH0383440U -

Info

Publication number: JPH0383440U
Application number: JP14224889U
Authority: JP
Priority date: 1989-12-08
Filing date: 1989-12-08
Publication date: 1991-08-26

Description

[Brief explanation of the drawing]

第１図は本考案一実施例ブロツク図。第２図は
従来例ブロツク図。１，２，３……リレー、４……負荷、５，６…
…変換回路、７……排他的論理和回路、８……遅
延回路、９……フリツプフロツプ、１０……警報
回路。 FIG. 1 is a block diagram of one embodiment of the present invention. FIG. 2 is a block diagram of a conventional example. 1, 2, 3...Relay, 4...Load, 5,6...
...Conversion circuit, 7...Exclusive OR circuit, 8...Delay circuit, 9...Flip-flop, 10...Alarm circuit.

Claims

[Claims for Utility Model Registration] 1. The relay winding of the relay to be detected is connected in series with a power source and an on/off switch, and the current supplied from the power source to the load is caused by the contacts driven by the relay winding. A malfunction detection circuit for a relay in a circuit whose opening/closing is controlled includes a first conversion circuit that converts a potential applied to the load into a polarity and potential suitable for a logic circuit; a second conversion circuit that converts the polarity and potential into a suitable polarity and potential; an exclusive OR circuit that receives each output of the first conversion circuit and the second conversion circuit as input; and an output logical value of the exclusive OR circuit. Therefore, through a switch circuit that is closed when the potential of the relay winding and the potential of the load do not match, and a contact of the relay to be detected that is energized by the current passing through this switch circuit, A malfunction detection circuit for a relay, comprising: a cutoff relay that cuts off the current supplied to the load; and an alarm circuit connected in parallel to a relay winding of the cutoff relay. 2. The relay malfunction detection circuit according to claim 1, further comprising a delay circuit provided in the output circuit of the exclusive OR circuit and providing a delay corresponding to the operating time of the relay.