JPH02119542A - Remote monitor - Google Patents

Abstract

PURPOSE:To miniaturize a remote monitor, and to reduce cost by installing a power cable, on one side of which a breaker is connected and on the other side of which a remote disconnector section and load are connected, and providing a DC circuit and a switch to be closed when the breaker is brought to a state of interruption to the power cable. CONSTITUTION:When the load side is maintained and inspected, a switch 15 is closed, a push-button switch 17 is pushed and DC currents from a DC power 13 are overlapped to power cables 1A-1C when a breaker 12 is led out to the position of disconnection from a switchboard 11. When a remote disconnecting section 3 is brought to a closed state, a closed circuit is constituted through a primary winding 5A, thus lighting a pilot lamp 16, then confirming the closing of the remote disconnecting section 3. When the remote disconnecting section 3 is brought to an open state, on the contrary, the closed circuit is not formed, thus generating no response in an overlapped signal, with no lighting of the pilot lamp 16.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a remote monitoring equipment device that has an improved confirmation device for confirming the opening/closing of a remote disconnect section installed at a remote location on the monitoring panel side.

[Conventional technology]

Generally, in a thermal power plant, coal is loaded onto a belt conveyor from a coal storage site several kilometers away and transported into the power plant. The power generation equipment that operates and stops the belt conveyor has a three-phase dynamic power cable installed between the power plant and the coal storage area, such as the load.1 The power power cable on the power plant side is connected to the switchboard; Enter and exit the circuit breaker. The belt conveyor is operated and stopped by turning on and off the circuit breaker. The dynamic power cable on the load side is equipped with a remote disconnect section and an instrument transformer. The remote disconnect section is opened when performing maintenance and inspection on the load side to ensure the safety of workers during maintenance and inspection. Potential transformers are used as control power sources for station lights, control equipment, etc. used as loads.

Since the power supply side circuit breaker and the remote disconnector are installed several kilometers apart, there is a risk that safety may be compromised if the power supply side does not know whether to open or close the remote disconnector. Therefore, safety is ensured by providing a separate control line between the remote disconnector and power generation, and by providing an indicator light on the power source side to indicate whether the remote disconnector is open or closed in response to the opening or closing of the remote disconnector.

[Problem to be solved by the invention]

However, if a control line is provided, not only does it require a corresponding area of equipment, but also the cost increases if the control line is laid over several kilometers.

In addition, as a remote monitoring and control device, Japanese Patent Application Laid-Open No. 62-272834
No. 2 can be mentioned.

[Means to solve the problem]

The remote monitoring device of the present invention has a dynamic cable with a circuit breaker connected to one side and a remote disconnecting section and a load connected to the other side, a DC circuit connected to the dynamic cable, and a circuit breaker that closes when the DC circuit is in a disconnected state. Equipped with a switch.

[Effect]

If the switch is closed with the circuit breaker cut off, the DC current of the DC circuit can be directly superimposed on the moving cable and transmitted, and received on the power supply side in response to the opening/closing pump of the remote disconnection section, which is different from conventional control. There is no need to lay cables, making it possible to downsize the remote monitoring equipment and reduce the cost of the equipment.

〔Example〕

Embodiments of the present invention will be described below using a remote monitoring device shown in the drawings.

Remote monitoring equipment is used in thermal power plants.

One side of the three-phase dynamic power cables LA, IB, and IC is connected to the load-side switchboard 2. The load-side switchboard 2 is installed on the coal storage site side, and is connected to the remote disconnection section 3. Load 4. An instrument transformer 5 is arranged.

Distant disconnect section 3. The load 4 is connected to the dynamic power cables IA to IC. The instrument transformer 5 is used as a power source for a control line (not shown), and is composed of a primary winding 5A and a secondary winding 5B.

The primary winding 5A is connected to dynamic power cables IA to IC. A voltmeter 6 and an interlock coil 7 are connected between the secondary windings. A power supply side switchboard 10 is installed on the other side of the dynamic power cables IA to IC.

The power supply side switchboard 10 is the side where the generator is installed.

It is structured as follows. A power supply side disconnection section 11A and a load side disconnection section 11B are installed inside the switchboard 11,
The circuit breaker 12 enters and leaves the switchboard 11.

When the circuit breaker 12 is connected to both disconnecting sections 11A and IIB, the contacts of the circuit breaker are turned on and off using a control line (not shown), and when the circuit breaker 12 is pulled out from the switchboard 1o,
Circuit breaker 12 and both disconnecting sections 11A.

There are cases where the connection with the IIB is removed and the connection is moved to the disconnection position to shut off the connection.

A DC circuit 14 is connected between the dynamic cables IA to IC between the load-side disconnection section 11B and the remote disconnection section 3 and the DC power supply 13. The DC circuit 14 includes a switch 152 and an indicator lamp 16. A push button switch 17 is installed. The switch 15 is used when the circuit breaker 12 is in the cutoff state, and opens when the circuit breaker 12 is in the closed state.

Next, when performing maintenance and inspection on the load side, the circuit breaker 12 is pulled out from the switchboard 11 to the disconnected position, the switch 15 is closed, and the pushbutton switch 17 is pressed.

DC current is superimposed from the DC power supply 13 onto the dynamic power cables IA to IC. If the remote disconnect section 3 is in an open state, an open circuit is formed via the negative winding 5A, so the indicator lamp 16 lights up and it can be confirmed that the remote disconnect section 3 is closed. On the contrary, if the remote disconnection section 3 is in the open state,
Since a closed circuit cannot be formed, there is no response to the superimposed signal, so the indicator lamp 16 does not light up.

As a result, in the present invention, when the circuit breaker 12 is pulled out from the switchboard 11 to the disconnection position, the switch 15 closes, and the open/closed state of the remote disconnection section 3 can be confirmed by the display lamp 16 on the power supply side using the dynamic cables IA to IC. This eliminates the need for control lines as in the prior art, which not only allows the remote monitoring device to be made more compact, but also reduces the cost of installing control lines.

〔Effect of the invention〕

As described above, the remote monitoring device of the present invention can be manufactured in a small size and at low cost.

[Brief explanation of drawings]

The figure is a circuit diagram of a remote monitoring device shown as an embodiment of the present invention. IA~IC...Moving power cable, 3...Far disconnection section,
5... Instrument transformer, 11A and IIB... Power supply side and load side disconnecting section, 12... Breaker, 14... DC circuit, 15... Switch.

Claims (1)

[Claims] 1. The circuit breaker enters and exits the distribution board, is electrically connected to and separated from the power supply side and load side disconnecting section of the distribution board, and is connected between the load side disconnecting section and a distant disconnecting section installed at a distance and the load. A remote monitoring device characterized in that a DC circuit is connected to the electric wire, a DC circuit is connected to the electric wire, and the DC circuit is provided with a switch that operates only when a circuit breaker breaks. 2. The remote monitoring device according to claim 1, wherein a DC circuit is connected to the load-side disconnection section. 3. The remote monitoring device according to claim 1, further comprising display means for indicating that current is flowing through the DC circuit. 4. The remote monitoring device according to claim 1, wherein the DC circuit is provided with an indicator light and a pushbutton switch. 5. The remote monitoring device according to claim 1, wherein a voltage transformer is used for the load. 6. The remote monitoring device according to claim 1, wherein a closed circuit is established between the electric wire and the DC circuit when the switch and the remote disconnecting section are closed. 7. Connect the circuit breaker to a remote disconnecting section installed far away and the load using an electric wire, connect a DC circuit to the electric wire, and create a closed circuit between the DC circuit and the electric wire depending on the operation of the remote disconnecting section. A remote monitoring device characterized in that the closed circuit is provided with a switch that closes in response to opening of a circuit breaker. 8. The remote monitoring device according to claim 7, wherein the closed circuit is established when the circuit breaker is cut off and the remote disconnection section is closed. 9. The remote monitoring device according to claim 7, wherein the DC circuit is provided with an indicator light and a pushbutton switch. 10. The remote monitoring device according to claim 7, wherein a voltage transformer is used for the load.