JP2745268B2 - Power switching device for relay with energy storage trip function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to switching between a normal power supply and a test power supply of a relay having an energy storage trip function.

[0002]

2. Description of the Related Art A conventional circuit diagram is shown in FIG. The input terminal portions 12a, 13a, 14a and the output terminal portion 15a of the relay 1 with the energy storage trip function (hereinafter, referred to as the relay 1) are connected to the switch 2 for drop-in. In addition, the regular power input 11 a of the relay 1 is connected to the secondary terminal 31 of the power transformer 3. The normal power input unit 1 is provided inside the relay 1.
The test power supply unit 1a and the test power supply input unit 11b are connected to the power supply unit 11 via a manual changeover switch 11e. During normal operation, the power of the relay 1 is supplied from the power transformer 3. At the time of testing the relay 1, the input terminals 12a, 13
a, 14a, and a test power supply input unit 11
The power is connected to b, and the test is performed by manually switching the changeover switch 11e.

[0003]

If the commercial power supply is established, the test can be performed without switching the changeover switch 11e, so that the operation of the changeover switch 11e may be forgotten. In this case, if the phases of the normal power supply and the test power supply are different, an error may occur in the test result. Further, even if the changeover switch 11e is switched before the test, the switching back of the changeover switch 11e may be forgotten after the test. In this case, in order to prevent forgetting to switch back the changeover switch 11e, the structure is such that the front panel or the like of the relay 1 cannot be attached when the changeover switch 11e is not turned back. Accordingly, the present invention provides a switch 11e at the time of testing the relay 1.
Provided is a power supply switching device that can automatically switch to a test power supply without operating the power supply.

[0004]

According to the present invention, there are provided a normal power input unit used during normal operation and a test power input unit used during testing. When there is an input to the test power input, the relay is operated by the input, and the power circuit is switched from the regular power input to the test power input.
When the input of the test power input unit is lost and the power supply circuit is switched back to the service power input unit, a circuit is provided in the relay for delaying the return operation of the relay for a period of time during which the charging trip operation of the relay is completed.

[0005]

According to the present invention, the power supply of the relay can be automatically switched or switched back depending on the presence or absence of the test power supply. Therefore, forgetting to switch back the changeover switch and error in the test result do not occur.

[0006]

FIG. 1 is a circuit diagram of a relay incorporating a power supply switching device according to an embodiment of the present invention. The relay 1 is connected to the switch 2 for drop-in and the power transformer 3. Relay 1
The input terminal portions 12a, 13a, 14a and the output terminal portion 15a are connected to the current transformer 22, the zero-phase transformer 2,
3, connected to the zero-phase current transformer 24 and the trip coil 25, respectively. The relay 1 has a regular power input unit 11a.
And a test power input unit 11b. The service power input unit 11a is connected to the secondary terminal 31 of the power transformer 3 and the power supply line 3.
Connected with 2.

[0007] Detecting units 12, 13, 14 and an output unit 15 are connected to the input terminal units 12a, 13a, 14a and the output terminal unit 15a, respectively. Those detection units 12, 1
3 and 14 and the output unit 15 together with the power supply unit 11
6 is connected. The processing unit 16 detects a short-circuit and ground fault accident based on the detection information of the current and voltage of the service line 20. The processing unit 16 outputs an overcurrent storage trip command when a short-circuit fault occurs, and outputs a ground fault trip command when a ground fault occurs, and operates the trip coil 25 of the pull-in switch 2 via the output unit 15. An opening operation of the main contact 21 of the switchgear 2 is performed.

The regular power input section 11a is connected to the relay b
The test power supply input section 11b is connected to the relay 11c via the contact.
Is connected to the power supply unit 11 through the contact a. Also,
The coil of the relay 11c is connected to the test power supply input section 11b, and operates and returns depending on the presence or absence of the input. In addition,
The delay circuit 11d performs the return operation of the relay 11c by the relay 1d.
1c is connected in parallel. Thus, when there is no input to the test power supply input section 11b, the normal power supply input section 11
Power is supplied to the power supply unit 11 from a. On the other hand, when there is an input to the test power supply input section 11b, the relay 11c operates and supplies power to the power supply section 11 from the test power supply input section 11b. When the input of the test power supply input section 11b is lost, the relay 11c returns to operation after the time T2 by the delay circuit 11d connected to the relay 11c, and the power supply section 11 supplies power from the regular power supply input section 11a. Is done.

When the relay 1 is tested, the input terminal 1
A test apparatus is connected to 2a, 13a, and 14a, and a test power supply is connected to the test power input section 11b. The overcurrent storage trip command is output from the processing unit 16 when the input terminal unit 12a has an input equal to or greater than the specified value and the input power to the power supply unit 11 is continuously lost for the time T1. With this output, the output unit 15 operates the trip coil 25. The input power to the power supply unit 11 is a normal power input unit 11a.
Alternatively, it is an input power from the test power input unit 11b.
In addition, even if the input power to the power supply unit 11 is lost, the time T1
The power supply unit 11 has a backup power supply for keeping the processing unit 16 operating during the above. Further, since the output unit 15 is a capacitor trip device, the output unit 15 is connected to the trip coil 2 even when the input power to the power supply unit 11 is lost.
5 can be operated. Therefore, FIG.
By setting the time T2 to be longer than the time T1, a test of the overcurrent accumulation trip operation can be performed with the input power from the test power input unit 11b. However, FIG.
If the time T2 is less than the time T1 (including the one without the delay circuit 11d), the test power supply is switched back to the normal power supply before the overcurrent storage trip command is issued. Therefore, the input power to the power supply unit 11 is not continuously lost during the time T1, and the test of the overcurrent storage trip operation cannot be performed. Although the above description has been given of the relay with the overcurrent accumulation trip function, the power supply switching device of the present invention can be applied to all the relays with the accumulation trip function.

[0010]

According to the present invention, in addition to the normal power supply input section used for normal operation, a test power supply input section used for testing the relay is provided. Therefore, when testing the relay, test power can be supplied from the test power input unit. Therefore, it is not necessary to remove the power supply line used during normal operation and perform the test. Also, by inputting a power supply for testing and a phase synchronization between the input from the test equipment and the input,
There is no error in the test results. Further, when a manual changeover switch is provided, the operation of changing over and changing back the changeover switch is necessary, and sometimes the changeover or the changeover is forgotten. However, by using the power supply switching device of the present invention, it is possible to automatically switch from the commercial power supply to the test power supply, and to automatically return from the test power supply to the commercial power supply after the end of the test. Therefore, there is no mistake such as forgetting to switch or switch back. Also,
Since it returns with time, it is very effective for testing a relay with an energy storage trip function.

[Brief description of the drawings]

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

FIG. 2 is a time chart illustrating power switching according to the present invention.

FIG. 3 is a circuit diagram conventionally implemented.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 relay with energy storage trip function 11 power supply section 11a regular power supply input section 11b test power supply input section 11c relay 11d delay circuit 12, 13, 14 detection section 12a, 13a, 14a input terminal section 15 output section 15a output terminal section 16 processing Part 2 Drop switch 20 Drop wire 21 Main contact 22 Current transformer 23 Zero-phase transformer 24 Zero-phase current transformer 25 Trip coil 3 Power transformer 31 Secondary terminal 32 Power supply line

Claims (1)

(57) [Claims] 1. A relay having an energy storage trip function having a normal power input unit used during normal operation and a test power input unit used for testing a relay, wherein an input is made to the test power input unit. Equipped with a relay that switches the power supply circuit from the regular power supply input section to the test power supply input section by input.If the input of the test power supply section is lost and the power supply circuit is switched back to the regular power input section, the energy storage trip operation is completed. A power switching device for a relay with an energy storage trip function, wherein a circuit for delaying the switching back is provided in the relay for a period of time longer than a predetermined time.