JPH0923565A - Monitoring circuit of protective relay device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To monitor the device successively even at the time of inspection of a protective relay device or a breaker, and detect trouble in its early stage, by adding a monitoring circuit in parallel with the trip coil or the make coil of a breaker. SOLUTION: If wire breaking occurs in a terminal TT1 for test, the trip coil TC of a breaker, a contact of a breaker, and further a cable connecting these, or the like, a current, which was flowing to the trip coil TC, flows through a photocoupler PC13 and a resistor R13. Thereupon, the current continues to flow to the photocouplers PC11 and PC12, and remains as it is electrically continuous, and it does not output output relay trouble. But, the photocoupler PC13 becomes electrically continuous, it is outputted as the trip circuit trouble through NOT 13 and AND 13. Accordingly, the necessity to lock the monitoring of the breaker trip circuit or the breaker make circuit vanishes, and it becomes possible to monitor them successively, and the trouble can be detected in its early stage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a monitoring circuit for a protective relay device having a constant monitoring function.

[0002]

2. Description of the Related Art In recent years, as the power system has become extremely high in voltage and is becoming more important, protective relay devices are required to have higher reliability. Generally, an automatic monitoring system is adopted to improve the reliability of the protective relay device itself. This automatic monitoring system is composed of two types of constant monitoring and automatic inspection, but the former constant monitoring mainly determines a malfunction side defect by determining an abnormality when an operation that cannot be performed normally continues for a certain period of time. It is a monitoring method.

One of the most important functions of the protective relay device is to constantly monitor the circuit breaker trip circuit and the circuit breaker closing circuit without exception, and the purpose of this monitoring is generally. Targets defects due to wire breaks. By any chance
Needless to say, when a break occurs in the circuit breaker trip circuit or the circuit breaker closing circuit, the circuit breaker is not issued with a trip command or a circuit closing command, so that the power system is greatly affected.

On the other hand, the latter automatic inspection is to automatically perform the periodic inspection work of the protective relay device, but at the time of the periodic inspection work of the protective relay device or the inspection work of the circuit breaker. In this case, it is general that the breaker trip circuit and the breaker closing circuit of the protective relay device are opened once. The circuit breaker trip circuit and the circuit breaker closing circuit are normally opened by a human system, especially when the protective relay is re-operated after the inspection work is completed and the circuit breaker trip circuit is opened. And the operation is restarted after confirming that the circuit breaker closing circuit is normal. All of these series of work are done by humans. Therefore, in the case of a protective relay device having a large number of circuit breaker trip circuits, it is the current situation that the working time is significantly long.

The above description will be described with reference to the conventional circuit breaker trip circuit shown in FIG. In the figure, P and N are control power supplies, 11a1 and 12a1 are relay contacts for a circuit breaker trip command, TT1 is a test terminal with a shorting piece, TC is a circuit breaker trip coil, and TCa1 is a circuit breaker a. Contact, SW1 is a switch for breaking the circuit, PC
11 and PC12 are photocouplers, R11 and R12 are resistors, AND13 is an AND circuit, and OR11 and OR12 are O.
The R circuit and NOT14 are NOT circuits.

At normal times, the circuit breaker trip command relay contacts 11a1 and 12a1 are "open" because they do not operate, and no trip current flows. Therefore, in a normal condition, the current determined by the constants of the resistors R11 and R12 is the photocoupler PC1.
1, through PC12 to the trip coil TC of the circuit breaker. This constantly flowing current is applied to resistors R11 and R12.
Is suppressed to a small value by the trip coil T of the circuit breaker.
It is considered that C does not work in any case.
In this way, a minute current constantly flows through the circuit breaker trip circuit TC, and the minute current causes the photocoupler PC1 to operate.
1, PC12 is conducting.

Therefore, if a break occurs in the test terminal TT1, the breaker trip coil TC, the a-contact TCa1 of the breaker, or the wire connecting them, no current will flow in the photocouplers PC11 and PC12. The photocouplers PC11 and PC12 become non-conducting and are output as a tripping circuit failure. Also, a photocoupler PC is provided in parallel with each of the circuit breaker trip command relay contacts 11a1 and 12a1.
11 and PC12 are directly connected to monitor the contact.

On the other hand, when the inspection work of the protective relay device and the inspection work of the circuit breaker are carried out regularly, in order to prevent unnecessary protective relay device operation output at the time of inspection, the test terminal TT1 is used.
The short-circuit piece of is removed. Therefore, the photo coupler PC1
1, because the minute current that was flowing to PC12 is cut off,
Lock the trip circuit fault output by monitoring lock.
Similarly, when the breaker is open, the trip circuit failure is locked.

Here, a flowchart of FIG. 8 shows an operation procedure for carrying out the periodical inspection work of the conventional protective relay device and the inspection work of the circuit breaker. That is, in the case of the periodic inspection work of the protective relay device and the inspection work of the circuit breaker, the monitoring is locked, and the short circuit piece of the test terminal TT1 is removed, and then the inspection of the protective relay device is started. After the regular inspection work of this protective relay device and the inspection work of the circuit breaker are completed and the short-circuit piece of the test terminal TT1 is connected before the operation is resumed, the upper part (P) of the test terminal TT1 is connected before the connection. Side) and measure the potential of the relay contacts 11a1 and 12a1 to confirm that they are open. At that time, photocouplers PC11 and PC1
Since the voltage circulates via 2, it was necessary to open the circuit with the switch SW1. When the short-circuit piece of the test terminal TT1 is connected, the monitor lock setting is released.

FIG. 6 is a conventional seal-in circuit diagram for tripping a circuit breaker. In the figure, P and N are control power supplies, 11
a2 and 12a2 are relay contacts for circuit breaker trip command, TT2
Is a test terminal with a short-circuit piece, X and Y are seal-in relays, FX and MX are contacts of the seal-in relay, TCa2 is a contact of a circuit breaker, SW2 is a switch for breaking the circuit, and PC21 and PC22 are Photo coupler, R21, R2
2 is a resistor, AND 23 is an AND circuit, OR 21 and OR 2
2 is an OR circuit, and NOT 24 is a NOT circuit.

In normal times, the circuit breaker trip command relay contacts 11a2 and 12a2 are "open" because they are inoperative, and no trip current flows. Therefore, in a normal condition, the current determined by the constants of the resistors R21 and R22 is the photocoupler PC2.
1, flowing through the PC 22 to the trip coil of the circuit breaker. This constantly flowing current is suppressed to a small value by the resistors R21 and R22, and it is considered that the seal-in relays X and Y do not operate in any case. In this way, a minute current always flows through the circuit breaker trip circuit, and this minute current causes the photocouplers PC21, PC
22 is conducting.

Therefore, when disconnection occurs in the test terminal TT2, the seal-in relays X and Y, the a-contact TCa2 of the breaker, and the electric wire connecting them, no current flows through the photocouplers PC21 and PC22. The photocouplers PC21 and PC22 become non-conducting and are output as a tripping circuit failure. In addition, a photo coupler P is provided in parallel with the contacts FX and MX of the seal-in relays X and Y, respectively.
Direct contact is monitored by connecting C21 and PC22.

On the other hand, when the inspection work of the protective relay device or the inspection work of the circuit breaker is carried out, in order to prevent unnecessary protective relay device operation output at the time of inspection, the test terminal TT2 is used.
The short-circuit piece of is removed. Therefore, the photo coupler PC2
1, Because the minute electric current that was flowing to PC22 is cut off,
Lock the trip circuit fault output by monitoring lock.
Similarly, when the breaker is open, the trip circuit failure is locked.

FIG. 7 is a circuit diagram of a conventional circuit breaker closing circuit. In the figure, P and N are control power supplies, 11a3 and 12a3 are circuit breaker closing command relay contacts, TT3 is a test terminal with a shorting piece, CC is a circuit breaker closing coil, and SW3 is a circuit breaking circuit. Switches, PC31 and PC32 are photocouplers, R31 and R32 are resistors, AND33 is an AND circuit, OR31 and OR32 are OR circuits, and NOT34 is NO.
This is a T circuit.

Normally, the relay contact 11 for the circuit breaker closing command
Since a3 and 12a3 are inactive, they are "open", and no making current flows. Therefore, in a normal state, the current determined by the constants of the resistors R31 and R32 is the photocouplers PC31 and PC3.
2 through the closing coil CC of the circuit breaker. This constantly flowing current is suppressed to a small value by the resistors R31 and R32, and it is considered that the closing coil CC of the circuit breaker does not operate in any case. As described above, a minute current constantly flows in the circuit breaker closing circuit, and the minute current causes the photocouplers PC31 and PC32 to be in conduction.

Therefore, the test terminal TT3 and the closing coil C
C, and if an electric wire or the like connecting them is disconnected, no current flows in the photocouplers PC31 and PC32, the photocouplers PC31 and PC32 become non-conductive, and the output is made as a closing circuit failure. Further, a photocoupler is connected in parallel with each of the circuit breaker closing command relay contacts 11a3 and 12a3 to directly monitor the contacts.

On the other hand, when the inspection work of the protective relay device and the inspection work of the circuit breaker are carried out, in order to prevent unnecessary protective relay device operation output at the time of inspection, the test terminal TT3 is used.
The short-circuit piece of is removed. Therefore, the photo coupler PC3
1, Because the minute current that was flowing to PC32 is cut off,
Locking the closing circuit output by monitoring lock. Similarly, when the circuit breaker is "open", the closing circuit failure is locked.

[0018]

As described above, in the prior art, when the protective relay is inspected or the circuit breaker is inspected, the faulty output is locked by the monitoring lock, so that the circuit breaker trip command is issued. It was not possible to directly monitor the relay contact and the breaker closing command relay contact.

Further, after the inspection of the protective relay device and the inspection of the circuit breaker are completed, it is necessary to perform a potential measurement work by a test before connecting the short-circuit piece of the test terminal when operating the protective relay device. The protective relay device with many terminals has problems such as long working time.

The present invention has been made to solve the above problems, and its purpose is to provide a relay contact and a breaker closing command for a breaker trip command when inspecting a protective relay or a breaker. The relay contact can be directly monitored, and the inspection of the protective relay and circuit breaker is completed, and when operating the protective relay device, measure the potential with the tester before connecting the test terminal short-circuit piece. It is an object of the present invention to provide a monitoring circuit for a protective relay device that does not require the work of

[0021]

In order to achieve the above object, claim 1 of the present invention provides a first relay contact and a second relay contact which are closed when a trip command or a closing command is given to a circuit breaker. And a protective relay having a circuit breaker trip circuit or a circuit breaker closing circuit in which a test terminal opened at the time of testing the protective relay device and a trip coil or closing coil of the circuit breaker are connected in series. A first monitoring circuit of an electric device, which is connected in parallel with the first relay contact and constantly monitors an operating state of the first relay contact.
Monitoring circuit, a second monitoring circuit which is connected in parallel with the second relay contact and constantly monitors the operating state of the second relay contact, and the test terminal and the trip coil or closing coil in series. A third monitoring circuit connected in parallel with the circuit for normally monitoring the test terminal and the series circuit of the trip coil or the closing coil, and being locked when the protection relay device is tested. Characterize.

According to a second aspect of the present invention, in the monitoring circuit of the protective relay device according to the first aspect, the first monitoring circuit, the second monitoring circuit and the third monitoring circuit are photocouplers. And

According to a third aspect of the present invention, the first relay contact and the second relay contact which are closed when the trip command or the closing command is given to the circuit breaker, and the protection relay device is opened when the protection relay device is tested. In a monitoring circuit of a protective relay device comprising a circuit breaker trip circuit or a circuit breaker closing circuit in which a test terminal and a trip coil or closing coil of the circuit breaker are connected in series, the first relay contact and The first coil is connected in parallel, and the first coil is operated depending on whether or not a minute current is flowing that does not operate the trip coil or the closing coil.
The first monitoring circuit for constantly monitoring the operating state of the relay contact and the second relay contact are connected in parallel, and the operating state of the second relay contact is constantly maintained depending on whether or not the minute current is flowing. A second monitoring circuit for monitoring; and a bipal circuit connected in parallel with the test terminal and the series circuit of the trip coil or the closing coil and bypassing the minute current when the test terminal is opened. It is characterized by doing.

According to a fourth aspect of the present invention, the first relay contact and the second relay contact which are closed when a trip command or a closing command is given to the circuit breaker and an open circuit when the protection relay device is tested. In a monitoring circuit of a protective relay device comprising a circuit breaker trip circuit or a circuit breaker closing circuit in which a test terminal and a trip coil or closing coil of the circuit breaker are connected in series, the first relay contact and A first monitoring circuit connected in parallel for constantly monitoring the operating state of the first relay contact; and a second monitoring circuit connected in parallel with the second relay contact for constantly monitoring the operating state of the second relay contact Monitoring circuit, the first monitoring circuit and the second monitoring circuit
And a display circuit that outputs a display when the open state of each relay contact is detected.

According to a fifth aspect of the present invention, a seal-in relay which is operated when an opening command or a closing command is given, a seal-in relay contact which is closed when the seal-in relay operates, and a test of the protective relay device are performed. In a monitoring circuit of a protective relay device that includes a seal-in circuit in which a test terminal that is opened at times is connected in series, the operating state of the seal-in relay contact is constantly monitored by being connected in parallel with the seal-in relay contact. The first monitoring circuit is connected in parallel with the series circuit of the test terminal and the seal-in relay, and the series circuit of the test terminal and the seal-in relay is normally monitored to check the protection relay device. And a second monitoring circuit that is locked at the same time.

According to a sixth aspect of the present invention, a seal-in relay which is operated when an opening command or a closing command is given, a seal-in relay contact which is closed when the seal-in relay is operated, and a test of the protection relay device are conducted. In a monitoring circuit of a protective relay device that includes a seal-in circuit in which a test terminal that is opened at times is connected in series, the operating state of the seal-in relay contact is constantly monitored by being connected in parallel with the seal-in relay contact. It is characterized by comprising a monitoring circuit and a display circuit which outputs a display when the monitoring circuit detects the open state of the seal-in relay contact.

[0027]

According to the monitoring circuit of the protective relay device of the present invention, by adding the monitoring circuit in parallel with the trip coil and the closing coil of the circuit breaker, the circuit breaker is inspected even when the protective relay device and the circuit breaker are inspected. Since it is not necessary to lock the monitoring of the trip circuit and the circuit breaker closing circuit, it is possible to continuously monitor and detect defects early.

[0028]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a circuit diagram of a protective relay device according to an embodiment of the present invention. The present embodiment is different from the conventional protective relay device of FIG. 5 in that the photocoupler PC13 and NOT are different.
Circuit NOT11, 12, 13, AND circuit AND11,
OR circuit OR13 and lamp L1 are added, and switch S
Since W1 is not necessary and the other points are the same, the same portions are denoted by the same reference numerals and duplicate description will be omitted.

As shown in the figure, the photocoupler PC11
The output state of the PC 12 and the output state of the PC 12 are detected by the AND circuit 11 through the NOT circuits 11 and 12 to detect whether one of the relay contacts 11a1 and 12a1 is closed, and when it is not closed, the lamp L1 is displayed. Now, the P side of the test terminal, which was conventionally performed when restarting the operation of the protective relay device, is no longer measured by the tester, and the short-circuit piece of the test terminal can be connected. As a result, the working time when the operation of the protective relay device is restarted can be greatly reduced. In addition, the circuit breaker trip circuit was previously monitored for disconnection via the photocouplers PC11 and PC12.
Just by adding the photocoupler PC13 and the NOT circuit 13, the disconnection can be monitored as in the conventional case.

Further, in this embodiment, by adding the photocoupler PC13 as described above, when the short circuit piece of the test terminal TT1 is opened or the breaker is opened when the protective relay or the breaker is inspected. In this case, since the monitoring current flows without interruption, the relay contact 11
Malfunction monitoring of a1 and 12a1 can be continued.

The flow chart of FIG. 4 shows an operation procedure for carrying out the periodical inspection work of the protective relay device and the circuit breaker inspection work according to the present embodiment. That is, in the case of the periodic inspection work of the protective relay device and the inspection work of the circuit breaker, the monitoring is locked and the test terminal T
Start the inspection of the protective relay device after removing the short-circuit piece of T1. When the inspection work of this protective relay device and the inspection work of the circuit breaker are completed, it is necessary to connect the short-circuit piece of the test terminal TT to restart the operation, but the lamp contacts L11 and 12a1 It can be confirmed that it is open. It is detected whether any one of the relay contacts 11a1 and 12a1 is not closed, and if it is not closed, the lamp L1 is displayed and the cause is investigated. When the lamp L1 displays, the short-circuit piece of the test terminal TT1 is connected and the monitoring lock setting is released.

Next, the function of defect detection will be described.
Normally, the circuit breaker trip command relay contacts 11a1 and 1
2a1 is "open" because it does not operate, and no trip current flows. Therefore, normally, a current determined by the constants of the resistors R11 and R12 flows through the trip coil TC of the circuit breaker through the photocouplers PC11 and PC12. This constantly flowing current is suppressed to a small value by the resistors R11 and R12, and it is considered that the trip coil TC of the circuit breaker does not operate in any case. In this way, a minute current constantly flows through the circuit breaker trip circuit TC, and the minute current causes the photocouplers PC11 and PC1 to operate.
2 is conducting. Note that no current flows through the photocoupler PC13 due to the resistor R13, and the photocoupler PC13 becomes non-conductive.

Therefore, when a disconnection occurs in the test terminal TT1, the trip coil TC of the circuit breaker, the a-contact TCa1 of the circuit breaker, or the wire connecting them, the current flowing in the trip coil TC is It flows through the photocoupler PC13 and the resistor R13. Then, current continues to flow in the photocouplers PC11 and PC12, the photocouplers PC11 and PC12 remain conductive, and no output relay failure is output. However, the photocoupler PC13 becomes conductive and is output as a tripping circuit failure via NOT13 and AND13. Further, by directly connecting the photocouplers PC11 and PC12 in parallel with the circuit breaker trip command relay contacts 11a1 and 12a1, the contacts are monitored. That is, for example, when the contact 12a1 is closed, the current that normally flows through the photocoupler PC12 will flow through the contact 12a1.
12 becomes non-conductive. As a result, an output relay failure is output via the OR13. Therefore, normally, the circuit breaker trip command relay contact 11a1 (including a relay that outputs the command), the contact 12a1, and the test terminal TT
1 and the circuit of the trip coil TC of the circuit breaker can be reliably monitored. Further, it is possible to distinguish and detect a defect of the contacts 11a1 and 12a1 (defective output relay) and a defect of the circuit of the test terminal TT1 and the breaker trip coil TC (defective trip circuit).

On the other hand, when the inspection work of the protective relay device and the inspection work of the circuit breaker are carried out, in order to prevent unnecessary protective relay device operation output at the time of inspection, the test terminal TT1 is used.
The short-circuit piece of is removed. For this reason, the minute current flowing to the test terminal TT1 side flows to the photocoupler PC13 and becomes conductive, and the NOT13 is established. However, the trip circuit failure output is locked by the AND13 via the OR12 and NOT14 by the monitoring lock. Similarly, when the breaker is open, the trip circuit failure is locked. However, in this case, a minute current continues to flow through the photocouplers PC11 and PC12 via the photocoupler PC13 and is in conduction. Therefore, even if the trip circuit failure is locked during inspection, the circuit breaker trip command relay contacts 11a1 and 12a1 can be continuously monitored. That is,
For example, when the contact 11a1 is closed, the photocoupler PC11
The current flowing through the contact point 11a1 flows through the contact point 11a1, and the photocoupler PC11 becomes non-conductive. As a result, an output relay failure is output via the OR13.

FIG. 2 is a seal-in circuit diagram for tripping a circuit breaker according to another embodiment of the present invention. As shown in the figure,
This embodiment is different from the prior art shown in FIG. 6 which has already been described. The photo coupler PC23 and the NOT circuits NOT21 and NOT21.
2, 23, AND circuit AND21, OR circuit 23, and lamp L2 are added, and the switch SW2 is not necessary. The other points are the same, and the same parts are denoted by the same reference numerals.

That is, the photocouplers PC21 and PC
The output state of 22 is ANDed through the NOT circuits 21 and 22.
In the circuit 21, it is detected whether one of the seal-in relay contacts FX and MX is closed, and when it is not closed,
By displaying the lamp L2, it is no longer necessary to measure the P side of the test terminal with the tester, which was conventionally performed when restarting the operation of the protective relay device, and connect the short-circuit piece of the test terminal. Is possible. As a result, the working time when the operation of the protective relay device is restarted can be greatly reduced. In addition, the circuit breaker trip circuit can be monitored for disconnection simply by adding the photo coupler PC23 and the NOT circuit 23.
The disconnection can be monitored in the same manner as the operation of the above embodiment.

Also in the present embodiment, by adding the photocoupler PC23 as described above, when the short circuit piece of the test terminal TT2 is opened or the circuit breaker is opened when the protective relay or the circuit breaker is inspected. When it is set to “open”, the monitoring current flows without interruption, so that malfunction monitoring of the seal-in relay contacts FX and MX can be continued.

FIG. 3 is a circuit diagram of a circuit breaker closing circuit which is still another embodiment of the present invention. As shown in the figure, the present embodiment is different from the prior art shown in FIG. 7 in that the photocoupler PC33, the NOT circuits NOT31, 32, 33, A
ND circuit AND31, OR circuit OR33 and lamp L3
Is added and the switch SW3 is unnecessary, and the other points are the same. Therefore, the same parts will be described with the same reference numerals.

That is, the photocouplers PC31 and PC
The output state of 32 is ANDed through the NOT circuits 31 and 32.
The circuit 31 detects whether any one of the relay contacts 11a3 and 12a3 is not closed, and when not closed, the lamp L3 is displayed to conventionally perform the operation when restarting the operation of the protective relay device. It is no longer necessary to measure the P side of the test terminal with a tester, and it is possible to connect the short-circuit piece of the test terminal. As a result, the working time when the operation of the protective relay device is restarted can be greatly reduced.
Also, the breaker closing circuit is monitored for disconnection by a photocoupler PC.
Just by adding 33 and the NOT circuit 33, disconnection monitoring can be performed similarly to the operation of the embodiment of FIG.

Also in this embodiment, by adding the photocoupler PC33 as described above, when the short circuit piece of the test terminal TT3 is opened or the circuit breaker is opened when the protective relay or the circuit breaker is inspected. When it is set to “open”, the monitoring current flows without interruption, so the relay contact 11
Malfunction monitoring of a3 and 12a3 can be continued.

In each of the above embodiments, the test terminal T
Although T1 to TT3 are supposed to be opened by a human system, they may be test terminals (contacts) that are automatically opened according to an inspection command. Further, the relay contact may be a static contact such as a thyristor. Also, photo couplers PC13, PC
23 and PC33 are eliminated, and resistors R13, R23 and R33 are eliminated.
Therefore, a bypass circuit that bypasses a minute current during a test may be used.

[0042]

As described above, according to the present invention,
Locking the circuit breaker trip circuit and circuit breaker closing circuit by adding a monitoring circuit in parallel with the circuit breaker trip coil and closing coil even when inspecting the protective relay and circuit breaker. It is possible to continuously monitor without needing to do so and to detect defects early. In addition, by adding a monitoring circuit in parallel with the trip coil and the closing coil, it is necessary to measure the potential with the tester each time when connecting the shorting piece of the test terminal of the circuit breaker trip circuit or the circuit breaker closing circuit. There is no effect, and the work time can be greatly shortened.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a second embodiment of the present invention.

FIG. 3 is a circuit diagram of a third embodiment of the present invention.

FIG. 4 is a flowchart showing the procedure of the present invention.

FIG. 5 is a circuit diagram of a conventional device.

FIG. 6 is another circuit diagram of the conventional device.

FIG. 7 is still another circuit diagram of the conventional device.

FIG. 8 is a flowchart showing a procedure of a conventional device.

[Explanation of symbols]

11a1, 11a2, 12a1, 12a2 ... Relay contacts for breaker tripping, L1, L2, L3 ... Lamp, PC11, PC
12, PC13, PC21, PC22, PC23, PC
31, PC32, PC33 ... Photo coupler, SW1, S
W2, SW3 ... Switch, TT1, TT2, TT3 ... Test terminal, TC ... Breaker trip coil, TCa1, T
Ca2 ... A contact of trip coil of breaker, X, Y ... Seal-in relay, FX, MX ... Contact of seal-in relay.

Claims (6)

[Claims] 1. A first relay contact and a second relay contact which are closed when a trip command or a closing command is given to a circuit breaker, and a test terminal which is opened at the time of a test of the protective relay device, In a monitoring circuit of a protective relay device including a circuit breaker trip circuit or a circuit breaker closing circuit in which a trip coil or a closing coil of a circuit breaker is connected in series, the monitoring circuit of the protective relay device is connected in parallel with the first relay contact. 1
A first monitoring circuit that constantly monitors the operating state of the relay contact; and a second monitoring circuit that is connected in parallel with the second relay contact and that constantly monitors the operating state of the second relay contact.
When the test terminal and the trip coil or the closing coil are connected in parallel with the series circuit, the test terminal and the trip coil or the closing coil series circuit are constantly monitored to test the protective relay device. And a third monitoring circuit that is locked, the monitoring circuit of the protective relay device. 2. The monitoring circuit of the protective relay device according to claim 1, wherein the first monitoring circuit, the second monitoring circuit, and the third monitoring circuit.
The monitoring circuit of the protective relay device, wherein the monitoring circuit of is a photocoupler. 3. A first relay contact and a second relay contact which are closed when a trip command or a closing command is given to the circuit breaker, and a test terminal which is opened during a test of the protective relay device. In a monitoring circuit of a protective relay device comprising a circuit breaker trip circuit or circuit breaker closing circuit in which a trip coil or a closing coil of a circuit breaker is connected in series, the monitoring circuit is connected in parallel with the first relay contact, and A first monitoring circuit that constantly monitors the operating state of the first relay contact depending on whether or not a minute current that does not operate the trip coil or the closing coil is flowing, and is connected in parallel with the second relay contact, A second monitoring circuit that constantly monitors the operating state of the second relay contact depending on whether or not the minute current flows, the test terminal and the trip coil, or the throwing coil. A monitoring circuit of a protective relay device, comprising: a parallel circuit connected to a series circuit of an input coil, the bypass circuit bypassing the minute current when the test terminal is opened. 4. A first relay contact and a second relay contact which are closed when a trip command or a closing command is given to the circuit breaker, and a test terminal which is opened during a test of the protective relay device. In a monitoring circuit of a protective relay device including a circuit breaker trip circuit or a circuit breaker closing circuit in which a trip coil or a closing coil of a circuit breaker is connected in series, the monitoring circuit of the protective relay device is connected in parallel with the first relay contact. 1
A first monitoring circuit that constantly monitors the operating state of the relay contact; and a second monitoring circuit that is connected in parallel with the second relay contact and that constantly monitors the operating state of the second relay contact.
A monitoring circuit for a protective relay device, comprising: a display circuit that outputs an output when both the first monitoring circuit and the second monitoring circuit detect the open state of each relay contact. 5. A seal-in relay that is operated when an opening command or a closing command is given, a seal-in relay contact that is closed when the seal-in relay operates, and a test that is opened at the time of testing the protective relay device. In a monitoring circuit of a protective relay device including a seal-in circuit in which terminals are connected in series, a first monitoring circuit connected in parallel with the seal-in relay contact and constantly monitoring an operating state of the seal-in relay contact, A second terminal connected in parallel with a series circuit of the test terminal and the seal-in relay to monitor the test terminal and the series circuit of the seal-in relay in a normal state, and locked during a test of the protective relay device; And a monitoring circuit for the protection relay device. 6. A seal-in relay which is operated when an opening command or a closing command is given, a seal-in relay contact which is closed when the seal-in relay is operated, and a test which is opened when the protective relay is tested. In a monitoring circuit of a protective relay device having a seal-in circuit in which terminals are connected in series, a monitoring circuit connected in parallel with the seal-in relay contact and constantly monitoring the operating state of the seal-in relay contact, and the monitoring circuit. A monitoring circuit for a protective relay device, comprising: a display circuit that outputs an output when the circuit detects an open state of a seal-in relay contact.