SU1119123A1 - Device for checking conditions of switching device in network - Google Patents

Abstract

A DEVICE FOR MONITORING THE CONDITION OF THE SWITCHING MACHINE IN THE NETWORK containing a repeater relay connected in series through the core of the communication cable with the signaling contact of the switching device, the output contacts of which are included in the signal circuit of the operating current circuit connected to ground and connected to the source current busbars, characterized in that, in order to simplify the device and enable monitoring of the insulation state of the relay-repeater during ohranenii detuning from false alarms in case a ground fault leads of the cable, it introduced an additional relay repeater connected through a second wire communication cable with signal contact of the switching device symmetrically with respect to the main relay, a repeater, and contacts both relepovtoriteley connected in series.

Description

The invention relates to electrical engineering, in particular, to the technique of relay protection, and can be used in the design of the protection of lines, tires and other objects.

Relay protection devices are known, containing at least one circuit of a logic relay-repeater and a resistor, connected directly to one pole and through a communication cable and the contacts of an external switching device to the other pole of the operating DC source 1.

In order to tune out the false positives of a logic relay, a repeater when a connecting cable is connected to ground (due to the presence of a connection to ground in an insulation control device connected to a source of operational direct current) is selected in series with the relay.

Ucp, 0,7UHOM, (1)

where CsrIinogng voltage at the terminals of the circuit, necessary for the relay to operate, and the rated voltage of the operating direct current source, respectively. Instead of a resistor, another adjustable or adjustable element, such as a relay spring, can be used.

However, in any case, the fulfillment of condition (1) is connected with the complexity of the fulfillment of another limiting condition.

and. , 8UH (, ", (2)

taking into account the voltage source voltage, which is 20% of the UHOM. The device closest to the proposed one is a device for monitoring the state of a switching device in the network, including a logic relay-repeater circuit, connected on both sides to the poles of the operating current source through communication cables and contacts external switching device (device with a bipolar gap) 2.

This device is fundamentally rebuilt from false positives when an earth fault occurs in one of the conductors of the communication cable.

The disadvantages of the known device are the complexity and high cost due to the need to have two communication channels between the logical relay-repeater and the switching device, as well as the lack of control over the state of isolation of the relay circuit 3.

The purpose of the invention is to simplify the device and to enable monitoring of the state of isolation of the relay-repeater circuit while maintaining detuning from false alarms in the event of an earth fault on the connecting cable.

The goal is achieved by the fact that in the device l control the state of the switching apparatus in the network, containing

a repeater relay, a series-connected communication cable core with a signal contact of a switching device, the output contacts of which are included in the circuit

signaling, as well as an element of control of isolating operational DC circuits, connected to ground and connected to buses of an operating current source, an additional repeater relay was connected through the second core of the communication cable to the signal contact of the switching device, symmetrically with respect to the main relay the repeater, and the contacts of both relay-repeaters are connected in series.

The contacts of the external switching device are connected between two logical relays and the earth fault of one of them cannot lead to the operation of both relays simultaneously. The drawing shows a diagram of the proposed device for monitoring the state of the switching apparatus.

The device contains logical relays 1 and 2, cores. 3 and 4 communication cables, signal contacts 5 of the external switching apparatus, contacts 6 and 7 of logical relay repeaters 1 and 2, external isolation control device 8, button 9, ballast resistors 10 and 11, button 12, galvanometer 13 signal relay, signal relay 14, button 15.

0 In the idle state of an external switching device, its signal contact 5 is open, logical relays 1 and 2 are in a de-energized state, and the circuit from the make contacts 6 and 7 is open. When the switching device actuates, its contact 5 closes, and from the current flowing through this contact and the cores of cable 3 and 4 under the action of the voltage Udvcr, relays 1 and 2 are activated, and the circuit from their series-connected contacts 6 and 7 is closed.

For normal operation of devices connected to the power buses, it is necessary to monitor the isolation of an extensive DC network 4, which is carried out by a special control device 8

5 isolation The device includes ballast resistors 10 and 11, galvanometer 13 relays 14, buttons 9, 12 and 15. If an unacceptable leakage to the ground occurs from one of the Unur tires. relay 14 is activated and signals this to the duty personnel, who take measures to eliminate the insulation defect.

At the same time, the formation of a path for the leakage current in the circuits of the proposed device for monitoring the state of the switching

5 of the device does not lead to its false triggering despite the presence of an isolation control device. For example, in the event of a short circuit to earth on one of the terminals of the signal contact of the switching device 5 (for example, on the right)

Repeater Relay 2 may work, but exclude false positives of the device.

since the relay 1 does not operate at the same time to monitor the state of the switching current (contact 5 is open), the circuit through the contact in the event of short circuits to the earth of the cable /

You are 6 and 7 relays 1 and 2 do not close the link. /

1119123д

Claims (1)

DEVICE FOR CONTROLING THE STATE OF THE SWITCHING AP NETWORK PART, containing a repeater relay connected in series through the core of the communication cable to the signal contact of the switching device, the output contacts of which are included in the signaling circuit, as well as an insulation control element for the operational DC circuits connected to ground and connected to the busbars of the operational source. current, characterized in that, in order to simplify the device and provide the ability to control the insulation state of the repeater relay circuit while maintaining the detuning from false alarms in the event of a short circuit After connecting the cable core to the ground, an additional repeater relay is introduced into it, connected through the second core of the communication cable to the signal contact of the switching device symmetrically with respect to the main repeater relay, and the contacts of both relays are connected in series.