SU845190A1 - Relay contact testing device - Google Patents

Description

I

The invention relates to automation, in particular, to devices controlling the presence of contact when microcurrents are passed through the contacts of the relay.

A relay control device containing a switch, a comparison unit and a fault fixing unit 1 is known. However, this device is not very reliable.

A device for monitoring relay contacts is known, which contains two delay elements, the inputs of which are connected to the outputs of the generator of switching on the relays, four of the logic element I, the first and second of which are connected to the indicators with their outputs, and the third and fourth to the first inputs of the corresponding two failure memory triggers 2

However, this device has poor contact monitoring, low sensitivity, a defect detection process is not automated, there is no program for the number of test relay cycles and low performance.

The aim of the invention is to increase the reliability of the control.

To do this, the device controlling the contacts of the relay, containing two delay elements, the inputs of which are connected to the outputs of the switching pulse generator, four elements AND, the first and second of which are connected to the indicators with their outputs, and the third and fourth to the first inputs of the respective two triggers storing of failures, a DC generator, a differential amplifier and a control time program block are introduced, the first and second inputs of the differential amplifier being connected respectively to the closing one and the other ykayuschemu

Claims (2)

10 contacts of the relay under test and through resistors to the output of the DC generator, the first and second outputs of the differential amplifier are connected respectively to the first inputs of the first and second elements j To and, the second inputs of which are connected to the outputs of the first and second failure triggers, the second inputs of which are connected to the reset switch, the outputs of the first and second delay elements are connected to the first inputs of the third and fourth elements AND, the second inputs of which are connected to the outputs of first- and second-AND elements, respectively, and the output time control program unit is connected to a control input of the pulse generator relay includant. The drawing shows a functional electrical circuit of the proposed device. The device contains an autonomous node consisting of a generator 1 of direct current, a generator 2 of switching on the relays of the block 3 of the monitoring time program, elements 4 and 5 of the delay and a switch 6 of resetting. In addition, the device contains cells for testing the contacts of the relay 7, each of which contains a differential amplifier 8, elements 9 and 10, indicators 11 and 12, elements 13 and 14, and failure triggers 15 and 16. The principle of operation of the plant is as follows. Microcurrents from the generator 1 through the opening and closing contacts of the relay 7 are fed to the corresponding inputs of the differential amplifier 8. The generator 2 switches on the tested relay 7. When the relay 7 is activated and there is a circuit for the microcurrent from the generator 1 through the closing contact of the relay at the element And 9, connected to the outputs of the amplifier 8, there is a high potential (+ 1). Due to the fact that, in the initial state, the failure memorizing trigger 15, connected to the AND 9 element, has at its output also a high potential. (+ 1) an “element 9” is triggered, which with the frequency of the generator 2, lights the indicator 11, indicating the presence of a contact. The generator 2 simultaneously with the switching pulses of the relay 7 to the inputs of the elements 13 and 14 gives out pulses of resolution of the control of the contacts with some delay on the elements 4 and 5. If the current does not pass through them after the closing contacts are closed, the element 9 does not work The output remains high and the AND indicator stops flashing. Since both potential elements of the input element And 13 will have a high potential, it will trigger the failure memory 15 trigger, which sends the "inhibit" signal to the input of the element 9, leaving the indicator 11 in the quenched state for the entire duration of the generator 2. The operating time of the generator 2 is determined ( set) block 3 time control programs. The principle of operation of the channel of control of normally closed contacts is similar to the operation of the channel of control of closing contacts. In this case, one half of the amplifier 8, element 10, indicator 12, element 14 and the failure memory trigger 16 are involved in the operation. The resetting of the memory triggers is reset by common switch 6. The contact monitoring is carried out taking into account the failure detection thresholds. Thus, in the proposed device, the quality of control is improved because of higher reliability and sensitivity, automation and simplicity, which increases reliability of operation. The invention The device controls the contacts of the relay, containing two delay elements, the inputs of which are connected to the outputs of the pulse generator, switching on the relay, four elements AND, the first and second of which are connected to the indicators with their outputs, and the third and fourth to the first inputs of the corresponding two memory triggers Failures, characterized in that, in order to increase the reliability of control, a DC generator, a differential amplifier and a control time program block are introduced, with the first and second inputs of the differential The special amplifier is connected respectively to the closing and opening contacts of the relay under test and through resistors to the output of the DC generator; the first and second outputs of the differential amplifier are connected respectively to the first inputs of the first and second elements AND, the second inputs of which are connected to the outputs of the first and second failure memory triggers , the second inputs of which are connected to the reset switch, the outputs of the first and second delay elements are connected to the first inputs by a third its and fourth elements are And, the second inputs of which are connected to the outputs of the first and second elements And, respectively, and the output of the monitoring time program block is connected to the control input of the switching pulse generator of the relay. Sources of information taken into account in the examination 1. Kostrynin A. N. Logical control of field-contact circuits. M .. Holy Hour, 1970, p. 80-86. 2. USSR author's certificate number 33L436, cl. H 01 H 47/00, 1971 (prototype).