JP3485976B2 - Remote test equipment for earth leakage breaker - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth leakage circuit breaker remote test device for remotely conducting an earth leakage test of an earth leakage circuit breaker.

[0002]

2. Description of the Related Art FIG. 6 is a circuit diagram of a remote tester for an earth leakage breaker disclosed in, for example, Japanese Utility Model Laid-Open No. 49-13322. In the figure, C is a zero-phase current transformer, a1 and a2 are line conductors, D is a tripping electromagnet, E is an overcurrent element having a time characteristic, F is a pseudo leakage circuit composed of contacts F1 and F2 and a resistor R, and S Is a switching contact part, G is a normally open earth leakage test switch, B1 and B2 are terminals of an earth leakage test circuit, H is a normally open remote test switch, and 11 is an earth leakage breaker.

In the apparatus shown in FIG. 6, when an operation test of the earth leakage breaker 11 is performed, if the normally open earth leakage test switch G is pressed and closed, the test currents are the resistance R, the earth leakage test switch G, the overcurrent element E, and the zero phase. The test current flows through the primary side conductor a1 of the current transformer C, and this test current becomes a pseudo leakage current. Due to this current, a secondary current is generated in the secondary coil of the zero-phase current transformer C, the tripping electromagnet D is excited, and the switching contact S is opened. If the operation test remotely connects the remote test switch H normally open to the connection terminals B1, B2 of the remote testing device, by the this closing remote test switch H produces a pseudo current leakage in the same manner as described above, A motion test can be performed.

[0004]

In the conventional remote test device as described above, the remote test switch H is connected by directly drawing the lead wires from the terminals B1 and B2 of the earth leakage test circuit in the body of the earth leakage breaker. The conductor a1,
There is a problem that the ground voltage of a2 appears at the terminal of the remote test device as it is, and it is dangerous if the terminal of the earth leakage test circuit is grounded due to careless handling. In addition, since line voltage is generated between the terminals of the remote test switch, it is not possible to connect remote test devices of different earth leakage breakers in parallel and perform a remote leak test collectively with one remote test switch. There was also a problem.

The present invention has been made to solve the above-mentioned problems, and even if a remote test device is attached to an earth leakage breaker and the earth leakage breaker is energized, a line is connected to a terminal of the remote test device. The result is a remote test device that does not generate voltage. Further, the present invention is intended to obtain a remote test device capable of connecting a plurality of remote test devices in parallel.

[0006]

A remote test device for an earth leakage circuit breaker according to the present invention outputs a trip signal for interrupting the line by detecting an imbalance due to a leakage of line current by a zero-phase current transformer. A leakage detection circuit that makes a pseudo leakage state of the line, and an opening / closing unit that artificially outputs a trip signal that cuts off the line from the leakage detection circuit,
A control means for controlling the opening / closing means by a remote test switch, wherein the controlling means is a constant current circuit, and the opening / closing means is an electrical opening / closing means including a thyristor,
The output of the constant current circuit is applied to the opening / closing means via a photo coupler to control the opening / closing of the opening / closing means.

Further, the main body of the earth leakage breaker, which includes the earth leakage detection circuit and the earth leakage test switch, and the control / opening / closing unit including the opening / closing means and the control means are housed in separate outer boxes. The outer box of the control / opening / closing part is attached to the outer surface of the.

Further, by connecting a plurality of control means in parallel to one remote test switch, and to perform remote testing of a plurality of earth leakage breakers by said remote test switch

[0009]

In the remote test device according to the present invention, the remote test switch is connected to the control means, and by operating the remote test switch, the opening / closing means controlled by the control means is opened / closed to create a pseudo earth leakage state. It is designed to operate the earth leakage detection circuit to perform a remote electric leakage test.However, the control means and the opening / closing means are the operation coil of the relay and the relay contact, or the control means and the opening / closing means are connected by a photo coupler. By doing so, they are electrically insulated from each other. Therefore, the line voltage of the earth leakage breaker is not directly applied to the remote test switch.

Further, because of the above configuration, it is possible to connect a plurality of remote test devices in parallel and perform a remote test of a plurality of earth leakage breakers at the same time by using one remote test switch.

[0011]

EXAMPLES Example 1. FIG. 1 is a diagram showing a circuit of an earth leakage breaker having a remote test device according to an embodiment of the present invention. In the figure, 14 is a control power supply, H is a normally open remote test switch, J1, J2
Is an input side terminal of the remote tester, 6 is a relay, and 6a is an operation coil of the relay 6, which is connected to the input side terminals J1 and J2. Reference numeral 6b is a normally open contact which is closed by applying a voltage to the operation coil 6a. Relay 6 operation coil 6
The a and the normally open contact 6b are electrically insulated. B
1, B2 are earth leakage test circuit terminals connected to the normally open contact 6b, 11 is an earth leakage breaker described in FIG. 6, and includes an earth leakage detection circuit 13, a current transformer C, an opening / closing contact portion S, and a tripping electromagnet D.
Including etc.

Now, when the remote test switch H is closed and the voltage V1 is applied from the AC or DC external control power source 14 to the input side terminals J1 and J2 of the remote test device, the relay 6
The operation coil 6a of is excited, the normally open contact 6b is closed,
Since the earth leakage test circuit terminals B1 and B2 of the earth leakage breaker 11 are short-circuited, the same state as when the earth leakage test switch G is closed is obtained, and the earth leakage test operation can be performed remotely. In this configuration, terminals B1 and B2 of the leakage test circuit connected to the line and input terminals J1 and J2 of the remote test device are connected.
Since and are insulated in the relay 6, the line voltage is not directly applied to the remote test switch H, and the safety during operation is maintained.

Example 2. FIG. 2 is a circuit diagram of an earth leakage breaker with a remote test device according to another embodiment of the present invention. In the figure, 2 is a rectifier circuit, 3 is a constant current circuit connected to the DC side of the rectifier circuit 2,
Reference numeral 16 is a photocoupler for coupling the output side of the constant current circuit 3 and the side of the thyristor circuit 7 described later, and its input side 16
By supplying a current to a, the output side 16b becomes conductive.
The constant current circuit 3 includes a resistor R1, a Zener diode ZD1 connected in series with the resistor R1, and an input side 16 of the photocoupler.
a resistor R5 connected in series with a and the input side 1 of the photocoupler
The smoothing capacitor C1 connected in parallel to the series circuit of 6a and the resistor R5, and the Zener diode ZD connected in parallel to the series circuit of the input side 16a of the photocoupler and the resistor R5.
2 and the resistor R4 in series, and the resistor R4 and the Zener diode ZD2 are connected at their bases to connect the base to the resistor R4.
One end is connected to a connection point between a transistor Q2 having an emitter connected to the other end of 4, and a collector of the transistor Q2 and the gate of an N-channel field effect transistor (FET) Q1. It consists of a resistor R2 whose ends are connected.

Reference numeral 7 is a thyristor circuit connected to the output side 16b of the photocoupler 16, 10 is a rectifier circuit for supplying direct current to the thyristor circuit 7, and B1 and B2 are leakage test circuit terminals connected to the AC side of the rectifier circuit 10. Is. The thyristor circuit 7 serving as an electrical switching circuit includes a thyristor CR1 connected to the output side 16b of the photocoupler 16 and
It comprises a resistor R11 connected between the gate and cathode of the thyristor CR1 and a resistor R10 connected between the gate of the thyristor CR1 and the rectifier circuit 10 through the output side 16b of the photocoupler. The rest of the configuration is similar to that of FIG.

By closing the remote test switch H, an AC or DC voltage V from the external control power supply 14 is obtained.
When 1 is applied to the input terminals J1 and J2 of the remote test equipment, in the case of alternating current, it is converted into direct current by the rectifier circuit 2,
In the case of direct current, the constant current circuit 3 is directly energized. The voltage converted into direct current is applied to the resistors R1 and R2 of the constant current circuit 3 and the Zener diode ZD1, and the N channel F
A potential difference occurs between the gate and source of ETQ1. When a potential difference occurs between the gate and source of the N-channel FET Q1, conduction is established between the drain and source of the N-channel FET Q1, and the resistor R5 and the photocoupler input side 16a are energized. When the external power supply 14 is an alternating current, since the current flowing through the resistor R5 and the photocoupler input side 16a is full-wave rectified by the rectifier circuit 2, the smoothing capacitor C1 smoothes the current flowing through the resistor R5 and the photocoupler input side 16a.

When the voltage applied to the resistor R5 and the photocoupler input side 16a exceeds the Zener voltage of the Zener diode ZD2, the Zener diode ZD2 becomes conductive and the resistor R
4 and the base-emitter of the transistor Q2 flow a current, and the collector-emitter of the transistor Q2 is electrically connected. When the collector-emitter of the transistor Q2 becomes conductive, a current flows from the resistor R2 toward the transistor Q2, and the voltage of the resistor R2 rises. Since the voltage between the resistor R2 and the gate-source of the N-channel FET Q1 is limited by the Zener diode ZD1, when the voltage of the resistor R2 rises, the gate-source voltage of the N-channel FET Q1 decreases and the N-channel FET Q1
Suppresses the current flowing between the drain and source of the. Also,
Both ends of the resistor R5 and the photocoupler input side 16a, that is, both ends of the smoothing capacitor C1 are connected to the zener diode ZD2.
, And the voltage generated between the base and emitter of the transistor Q2 are maintained at a certain constant voltage.
Therefore, the current made to have a constant value by the resistor R5 flows to the photocoupler input side 16a. When a current flows through the photocoupler input side 16a, the photocoupler output side 16b becomes conductive.

The voltage between the leakage test circuit terminals B1 and B2 is converted into direct current by the rectifier circuit 10. When the photo coupler output side 16b becomes conductive, the photo coupler output side 16b
b, through the resistor R10, the gate of thyristor CR1
There is conduction between the cathodes. When the thyristor CR1 conducts, the earth leakage test circuit terminals B1 and B2 are pressed in the same manner as when the earth leakage breaker 11 is pressed to close the earth leakage test switch G.
Is short-circuited, and the earth leakage breaker 11 performs an earth leakage operation. In the configuration of the second embodiment, the input side terminals J1 and J2 are
It is possible to widen the allowable input voltage range of the voltage V1 to be applied to, for example, AC100V and AC200V can be shared.

Example 3. In recent years, the external shape of the earth leakage circuit breaker is becoming smaller, and it is possible to house the control / opening / closing portion including the relay 6 of FIG. 1 or the constant current circuit 3 and the thyristor circuit 7 of FIG. 2 in the earth leakage circuit breaker body. It is becoming difficult, and since the remote test device is an optional device that is installed according to the user's request, it is uneconomical in terms of cost to install the control / opening / closing part in all the earth leakage breakers. The third embodiment is an example for coping with this.

FIG. 3 is a circuit diagram of a remote tester for an earth leakage breaker according to the third embodiment, and FIG. 4 is a front view showing its outer shape. In these figures, 12 is a control / opening / closing part, that is, an outer box for housing the constant current circuit 3, the thyristor circuit 7, and the like.
The other configuration is the same as the description of the first and second embodiments, and thus the description is omitted. The outer box 12 is an earth leakage breaker 11
It has a structure that can be mounted on the side of the
It is configured to be connectable to the rectifier circuit 10 via the leakage test circuit terminals B1 and B2 extended from the leakage test switch G. Further, the outer box 12 has terminals J1 and J2 for connecting a control power source and a remote test switch H to the control / opening / closing part.
Is provided.

FIG. 4 shows a state in which the control / opening / closing portion is housed in the outer box 12 which is separate from the main body of the earth leakage breaker 11 and is attached to the side portion of the earth leakage breaker 11. According to the configuration, the device can be attached and detached accordingly, so that the above-mentioned demand can be addressed. The control / opening / closing unit housed in the outer box 12 is not limited to that shown in FIG. 3, and may be the circuit of the control relay 6 in FIG.

Example 4. FIG. 5 shows an embodiment in which the remote tester for an earth leakage breaker according to the present invention has a circuit configuration capable of performing a batch test. Reference numeral 11 is a plurality of earth leakage breakers, and 12 is an outer box accommodating a control / opening / closing portion, which is mounted on a side portion of each earth leakage breaker 11. Then, the input terminals J1 and J2 provided in each outer box 12 are connected in parallel, and these are connected to one remote test switch H and the control power supply 14. With this configuration, 1
By operating the individual remote test switches H, it is possible to simultaneously perform a remote test of a plurality of earth leakage breakers 11. Such a batch test circuit configuration has an output contact side of the control / open / close section, that is, the leakage test circuit terminals B1 and B2 and the control input side J.
This can be realized by electrically insulating 1 and J2.

[0022]

As described above, according to the present invention, since the input side and the output side of the remote test device are electrically insulated, the remote control line or the remote test switch which is the input side of the remote test device is connected. The line voltage of the earth leakage breaker is not applied, ensuring not only safety during operation, maintenance and inspection, but also a constant current circuit is used for the control unit of the remote test device, and the switching unit is controlled via a photo coupler. With that,
Since the constant current circuit widens the drive voltage range of the photocoupler, the control power supply voltage to the remote test device is, for example, 100V.
But even at 200V, the same remote test equipment can be used for both.

Further, as described above, since the input side and the output side of the remote test device are electrically insulated, the remote test devices for a plurality of earth leakage breakers are connected in parallel, and one remote test switch is connected. Can be tested at the same time.

Furthermore, by storing the earth leakage breaker and the remote test device in separate outer boxes, and mounting the remote test device on the outer surface of the outer case of the earth leakage breaker as required, the cost can be reduced. It can be reduced.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a remote tester for an earth leakage breaker according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a remote tester for an earth leakage breaker according to a second embodiment of the present invention.

FIG. 3 is a circuit diagram showing a remote tester for an earth leakage breaker according to a third embodiment of the present invention.

FIG. 4 is a front view showing an appearance of a remote tester for an earth leakage breaker according to a third embodiment.

FIG. 5 is a circuit diagram showing a remote tester for an earth leakage breaker according to a fourth embodiment of the present invention.

FIG. 6 is a circuit diagram showing a conventional remote tester for an earth leakage breaker.

[Explanation of symbols]

C zero-phase current transformer, D tripping electromagnet, G earth leakage test switch, H remote test switch, S open / close contact,
2 rectifier circuit, 3 constant current circuit, 6 control relay, 6a
Operating coil, 6b normally open contact, 7 thyristor circuit,
10 rectifier circuit, 11 earth leakage circuit breaker, 12 control / switch outer box, 13 earth leakage detection circuit, 14 control power supply, 16
Photo coupler.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-88369 (JP, A) JP-A-1-303014 (JP, A) JP-A-5-82008 (JP, A) JP-A-6- 203735 (JP, A) JP-A-6-20565 (JP, A) Actual development 59-25145 (JP, U) Actual development 5-48189 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01H 83/02 H01H 83/04

Claims (3)

(57) [Claims] 1. A leakage detection circuit for detecting an imbalance due to a leakage of a line current by a zero-phase current transformer and outputting a trip signal for shutting off the line, a pseudo leakage state of the line is artificially created. The earth leakage detection circuit is provided with an opening / closing means for outputting a trip signal for cutting off the line, a control means for controlling the opening / closing means by a remote test switch, the control means is a constant current circuit, and the opening / closing means is a thyristor. A remote test device for an earth leakage breaker, characterized in that it comprises an electrical switching means including the above, and controls the opening / closing of the opening / closing means by adding the constant current circuit output to the opening / closing means via a photocoupler. 2. An outer box of the main body of the earth leakage breaker, the main body of the earth leakage breaker including the earth leakage detection circuit and the earth leakage test switch, and the control / opening / closing unit including the opening / closing means and the control means are housed in separate outer boxes. The remote test device for the earth leakage breaker according to claim 1, wherein an outer box of the control / opening / closing part is attached to the outer surface of the device. Connect wherein a plurality of control means in parallel to one remote test switch, according to claim 1 or claims, characterized in that to perform the remote testing of a plurality of earth leakage breakers by said remote test switch Item 2. A remote tester for an earth leakage breaker according to Item 2 .