JP2000152487A - Earth leakage breaker restoring device and circuit breaker using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically restore an earth leakage breaker by detecting the earth leakage breaker having worked by the transient cause such as thunder surge or the like other than overcurrents. SOLUTION: When an overcurrent flows to an apparatus on load side such as a commutation apparatus 60, etc., an overcurrent detector 20 having a current transformer 21 detects the overcurrent, and the relay 32 of a state keeper 30 is self-retained. Since the break contact 323c of the relay 32 becomes off, the supply of power to the motor 41 of a driver 40 is stopped. Even if an earth leakage breaker 10 works, the lever 16 for switching is not restored. When the earth leakage breaker 10 works with thunder surge, the relay 32 does not work since there is no detection of overcurrents by the overcurrent detector 20. Accordingly, the break contact 32c is on, so when microswitches 42 and 43 turned on through the lever 16 for switching, the motor 41 of the driver 40 works, and pushes up a switching rod 52, and the earth leakage breaker 10 is restored.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth leakage breaker restoring device for restoring an earth leakage breaker operated due to a transient cause such as a lightning surge, and a circuit breaker using the same.

[0002]

2. Description of the Related Art Conventionally, power supply to a communication device mounted on an upper portion of a communication pole, such as a repeater of a mobile phone, is performed by using a ground fault circuit breaker having an overcurrent cut-off function from a commercial power supply such as 100 V AC. Have gone through. The earth leakage breaker is equipped with a differential current transformer.If a difference occurs in the current of each line due to electric leakage due to insulation breakdown of the equipment on the load side, a current is generated on the secondary side of this differential current transformer, By detecting this, the circuit is cut off to prevent an electric shock accident or the like. A general earth leakage breaker has a characteristic of shutting off within 0.1 second with an earth leakage current of 25 mA to 30 mA. On the other hand, the overcurrent cutoff function of the earth leakage breaker detects a load current exceeding the rated current (for example, 15 A) as in the case of a normal circuit breaker, and cuts off the circuit by detecting this. is there. The cutoff time for the load current is, for example, non-operation at the rated current, within 60 minutes at a current 1.25 times the rated current, and within 2 minutes at a current twice the rated current. Has time characteristics.

In such an earth leakage breaker, for example, when an earth leakage occurs due to insulation deterioration of a communication device on the load side and an earth leakage current flows from the power supply line to the ground, the leakage is detected and the circuit is shut off. If the communication device on the load side breaks down and a current exceeding the rated current flows continuously for several seconds to several minutes, the overcurrent cutoff function operates and the circuit is cut off. In this way, the use of an earth leakage circuit breaker with an overcurrent interruption function detects leakage or a failure in a communication device, shuts off the circuit, and stops power supply to this communication device, causing an accident or failure. It was designed to suppress the spread.

[0004]

However, the conventional earth leakage breaker has the following problems. For example, in a communication device such as a cellular phone repeater mounted on a communication pole, a varistor or a varistor is provided between the power line and the ground to prevent damage caused by a lightning surge that enters through the power line. Lightning arresters and other lightning arresters are provided. This allows
The lightning surge induced by the power supply line and invading is discharged to the ground via the lightning arrester to prevent the communication equipment from being damaged. When power is supplied to such a communication device through an earth leakage breaker, when a lightning surge flows from the power line to the ground, a difference occurs in the current flowing through each power line, and the earth leakage breaker operates. The circuit is interrupted. In this case, since there is no abnormality in the communication device protected by the lightning arrester, the normal state can be immediately restored by reconnecting the earth leakage breaker. According to a certain statistic, it is reported that 80 to 90% of the shut-off operations of the earth leakage breaker used for such a communication device are restored only by re-input.

[0005] However, in order to restore the conventional earth leakage breaker, it is necessary to operate the opening / closing lever provided on the front of the earth leakage breaker. In addition, there is a problem that it takes a long time to recover because of going to the site and working.
The present invention solves the problems of the prior art, detects that the earth leakage breaker has been activated for reasons other than overcurrent,
An object of the present invention is to provide an earth leakage breaker recovery device that automatically recovers without manual intervention, and a circuit breaker using the same.

[0006]

Means for Solving the Problems To solve the above problems, a first aspect of the present invention is an earth leakage circuit breaker restoring device, which is connected to a circuit opening / closing lever of the earth leakage circuit breaker,
A mechanism for moving the lever from the open position to the closed position when the earth leakage breaker detects an earth leakage current flowing from the power supply side to the load side power supply line and cuts off the power supply to the load side circuit. And an overcurrent detection unit that monitors a load current flowing from the power supply side to the power supply line on the load side, detects when the load current exceeds a predetermined value, and outputs an overcurrent detection signal. Have. Further, the earth leakage breaker recovery device, a signal holding unit that holds an overcurrent detection signal output from the overcurrent detection unit, when the earth leakage breaker is activated and the lever moves to the open position, And a drive unit for driving the mechanism unit to return the lever from the open position to the closed position if the overcurrent detection signal is not held in the signal holding unit.

[0007] According to the first invention, since the earth leakage breaker recovery device is configured as described above, the following operation is performed. The load current is monitored by the overcurrent detection section, and if the load current exceeds a predetermined value, the overcurrent detection section outputs an overcurrent detection signal. The overcurrent detection signal output from the overcurrent detection unit is held by the signal holding unit.
Here, when the leakage breaker operates and the lever for opening and closing the circuit moves to the open position, the overcurrent detection signal is held in the signal holding unit, so the driving unit does not operate and the leakage breaker is not restored. . On the other hand, if the load current does not exceed a predetermined value when the earth leakage breaker is activated and the circuit opening / closing lever is moved to the open position, the signal holding unit does not hold the overcurrent detection signal. Then, the drive unit operates to move the lever from the open position to the closed position via the mechanism unit. Thereby, the earth leakage breaker is restored.

According to a second aspect of the present invention, the overcurrent detecting section and the signal holding section in the earth leakage breaker restoring device according to the first aspect of the present invention are configured as follows. That is, the overcurrent detection unit includes a current transformer that outputs a secondary current according to a primary current flowing from the power supply side to the power supply line on the load side, and a dc voltage that rectifies the secondary current of the current transformer. A constant voltage circuit that generates a stable and constant power supply voltage from the DC voltage when the DC voltage generated by the rectifier circuit exceeds a required voltage; Power supply voltage is supplied,
A voltage comparison circuit that compares the DC voltage generated by the rectifier circuit with a reference voltage and outputs the overcurrent detection signal when the DC voltage exceeds the reference voltage. The signal holding unit is configured to convert the overcurrent detection signal output from the voltage comparison circuit into an optical signal, and to control a conduction state of the semiconductor switch by the optical signal, and to be connected in series to the photoswitch. A relay coil and a relay having a relay contact which is attracted by a current flowing through the relay coil when the photo switch is turned on to form a self-holding circuit.

According to the second aspect, the following operation is performed in the overcurrent detection section and the signal holding section. In the overcurrent detection unit, the load current is converted into a secondary current by a current transformer, and guided to a rectifier circuit to generate a DC voltage.
If the generated DC voltage exceeds the required voltage, a constant power supply voltage is generated from the DC voltage by the constant voltage circuit. The power supply voltage is supplied to a voltage comparison circuit, and the voltage comparison circuit compares the DC voltage generated by the rectifier circuit with a reference voltage to detect the presence or absence of an overcurrent. When an overcurrent is detected and an overcurrent detection signal is output from the voltage comparison circuit, the overcurrent detection signal is supplied to a photo switch of the signal holding unit, and the conduction state of the semiconductor switch is controlled. When the photo switch is turned on, a current flows through the relay coil, and a self-holding circuit is formed by the relay contact attracted by the coil, and the overcurrent detection signal is held.

According to a third aspect of the present invention, in a circuit breaker, a switch unit for detecting a leakage current flowing in a load side circuit to cut off power supply to the load side circuit, and recovering the switch unit from outside. Circuit breaker having a circuit opening / closing lever for the circuit, and the earth leakage breaker restoring device of the first or second invention. According to the third aspect, the following operation is performed in the circuit breaker. If an overcurrent is detected by the earth leakage breaker recovery device when the leakage breaker of the circuit breaker is activated and the switch section is cut off, the earth leakage breaker recovery device does not operate and the switch of the earth leakage breaker does not operate. Department is not restored. On the other hand, if the overcurrent is not detected by the earth leakage breaker restoring device, the earth leakage breaker restoring device operates and the switch of the earth leakage breaker is restored.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment FIG. 1 is a configuration diagram of a circuit breaker according to a first embodiment of the present invention, and FIG. 2 is a perspective view showing an appearance of the circuit breaker of FIG. It is. This circuit breaker, when supplying commercial power such as 100V AC to a communication device attached to the upper part of a communication column, such as a repeater of a mobile phone, for example, prevents leakage or overcurrent due to failure of the communication device. This is for detecting and shutting off the power supply circuit to prevent the propagation of a fault. The circuit breaker includes an earth leakage breaker 10, an overcurrent detector 20,
It comprises a signal holding unit 30, a driving unit 40, and a mechanism unit 50.

The earth leakage breaker 10 detects an earth leakage due to insulation breakdown of a device on the load side and shuts off a circuit.
Power supply side terminal 11 to which a power supply such as AC 100V is applied
a and 11b. The terminals 11a and 11b are connected to the terminals 14a and 14b on the load side via the switches 12a and 12b and the primary side of the differential current transformer 13, respectively.
The differential current transformer 13 is configured such that a current flows through a secondary winding according to a difference between currents flowing through two primary-side wires. The detection unit 15 is connected to the secondary side. The detecting unit 15 switches the switching unit 12 in a short time (for example, within 0.1 second) when the current flowing through the secondary winding of the differential current transformer 13 exceeds, for example, 25 mA.
a, 12b are opened, and the switch units 12a, 12b are opened.
An opening / closing lever 16 for mechanically opening 12b is connected. The lever 16 has a structure in which the switch units 12a and 12b that have been opened can be closed by an external operation.

The earth leakage breaker 10 has an overcurrent interruption function for detecting a load current exceeding a rated current (for example, 15 A) and interrupting the circuit by detecting this.
The overcurrent cut-off function is, for example, inoperable at a rated current by flowing a load current through a bimetal (not shown), within 60 minutes at a current 1.25 times the rated current, and 2 minutes at a current twice the rated current. This is a function of shutting off the switch sections 12a and 12b with an interrupting time characteristic according to the overcurrent, such as within. The overcurrent detection unit 20 monitors a load current flowing from the power receiving terminals 1a and 1b connected to a commercial power supply such as AC 100V to the circuit on the load side through the power supply line 1, and this load current has a predetermined value (for example, 15A). ), An overcurrent detection signal is output. This overcurrent detector 2
0 has a current transformer 21 provided between the power receiving terminal 1b and the terminal 11b of the earth leakage breaker 10. Current transformer 21
Outputs a secondary current according to the primary current flowing from the power receiving terminal 1b to the earth leakage breaker 10. The secondary winding is connected to the AC input side of the rectifier circuit 22. The rectifier circuit 22 includes, for example, a bridge-connected rectifier diode, a smoothing capacitor, an output voltage limiting zener diode, and the like, and rectifies a secondary current of the current transformer 21 to generate a DC voltage. It is. For example, when a current of 15 A flows through the primary side of the current transformer 21, the output voltage of the rectifier circuit 22 is set to 8V.

The output side of the rectifier circuit 22 includes a constant voltage circuit 2
3 are connected. The constant voltage circuit 23 generates and outputs a stable and constant power supply voltage (for example, 5 V) when the output voltage of the rectifier circuit 22 is equal to or higher than a required voltage (for example, 8 V). A power supply voltage to the voltage comparator 24 is supplied from the output side of the constant voltage circuit 23. The voltage comparator 24 compares the voltage applied to the + input terminal with the voltage applied to the − input terminal,
When the voltage at the + input terminal is higher, a signal of level “H” (ie, an overcurrent detection signal) is output from the output terminal. On the other hand, when the power supply voltage supplied from the constant voltage circuit 23 is equal to or lower than a predetermined voltage, or when the voltage of the − input terminal is higher, the level of the output terminal of the voltage comparator 24 becomes “L”. The output voltage of the rectifier circuit 22 is divided by resistors 25 and 26 and applied to the + input terminal of the voltage comparator 24. Also, the-input terminal:
A reference voltage generated by a series circuit of a resistor 27 and a zener diode 28 connected to the output side of the constant voltage circuit 23 is applied. The signal holding unit 30 is connected to the output side of the voltage comparator 24.

The signal holding unit 30 holds the overcurrent detection signal detected by the overcurrent detection unit 20, and has a photo switch 31 and a relay 32. The photo switch 31 includes the light emitting diode 31a and the semiconductor switch 3
1b, when a current flows through the light emitting diode 31a and light is output, the resistance of the semiconductor switch decreases and the semiconductor switch is turned on. Light emitting diode 3
The output side of the voltage comparator 24 is connected to 1a. The relay 32 includes a relay coil 32a, a make contact 32b,
And a break contact 32c. One end of the relay coil 32a is connected to the power receiving terminal 1a via the reset switch 33, and the other end of the relay coil 32a is connected to one end of the semiconductor switch 31b of the photo switch 31. The other end of the semiconductor switch 31b is connected to the power receiving terminal 1b. Make contact 32b
Are connected in parallel to the semiconductor switch 31b. The reset switch 33 is a momentary switch that is turned off when pressed.

The drive unit 40 is connected to the signal holding unit 30 when the earth leakage breaker 10 is operated and the lever 16 is moved to the open position.
If the overcurrent detection signal is not held in the
To restore the lever 16 from the open position to the closed position. The drive unit 40 has two micro switches 42 and 43 connected in parallel with the motor 41. One end of the motor 41 is connected to the power receiving terminal 1b, and the other end of the motor 41 is connected to one ends of the micro switches 42 and 43. The other ends of the microswitches 42 and 43 are connected to the power receiving terminal 1 a via a break contact 32 c of the relay 32. The mechanism unit 50 includes the earth leakage breaker 10
For moving the circuit opening / closing lever 16 from the open position to the closed position. The cam 51 is driven by the motor 41 of the drive section 40, and the movement of the cam 51 is changed to a vertical movement and transmitted to the lever 16. An opening / closing rod 52 is provided.

The cam 51 is provided with a notch 51a, and the micro switch 42 is turned off when the lever 16 is completely returned to the closed position by the opening / closing rod 52. The opening / closing rod 52 is provided with a convex portion 52a, and is arranged so that the microswitch 43 is turned on when the circuit is cut off and the lever 16 of the earth leakage breaker 10 is in the open position. A communication device 60 such as a telephone repeater is connected to the terminals 14a and 14b on the load side of the earth leakage breaker 10 in such a circuit breaker.
Is connected. On the power input side of the communication device 60, varistors 61a and 61b for lightning surge protection are provided, and the ground GN is connected via these varistors 61a and 61b.
D.

Next, the operation of the circuit breaker shown in FIG.
(1) The operation at the time of lightning surge and (2) the operation at the time of overcurrent will be described separately. (1) Operation during Lightning Surge Suppose that a lightning surge induced from lightning is superimposed and applied to the commercial power supplied to the power receiving terminals 1a and 1b of the circuit breaker. The lightning surge enters the communication device 60 on the load side via the earth leakage breaker 10. Since varistors 61a and 61b for protecting the repeater and the like from lightning surge are provided on the power input side of the communication device 60, the lightning surge is discharged to the ground GND via the varistor 61a, for example. The current caused by the lightning surge is
Although the current flows from the terminal 1a through the terminal 14a to the ground GND via the varistor 61a, it does not flow in the path passing from the terminal 11b to the terminal 14b. There is a difference. As a result, a current flows through the secondary winding of the differential current transformer 13, and the detection unit 15 detects this to drive the lever 16, and the switch unit 12 a,
12b is opened and the power supply to the communication device 60 is cut off.

At this time, the power receiving terminal 1b and the earth leakage breaker 10
Since the overcurrent exceeding 15 A does not flow through the power supply line 1 between the power supply line 1 and the terminal 11b, the current on the secondary side of the current transformer 21 of the overcurrent detection unit 20 is small, and the output voltage of the rectifier circuit 22 is 8V.
It is as follows. Therefore, the output signal of the voltage comparator 24 is "L". Therefore, the photo switch 31 of the signal holding unit 30 remains off, the relay 32 does not operate, and the break contact 32c is on. When the earth leakage breaker 10 is cut off and the lever 16 moves to the open position,
The opening / closing rod 52 of the mechanism 50 connected thereto is moved downward as indicated by an arrow X in the figure. Thereby, the convex portion 52a of the opening / closing rod 52 is
When the movable piece of No. 3 is pushed down, this micro switch 43 is turned on. Further, the cam 51 is linked with the opening / closing rod 52.
Is rotated, the movable piece of the micro switch 42 is pushed up, and the micro switch 42 is also turned on.

When the microswitches 42 and 43 are turned on, the break contacts 32c connected in series with the microswitches 42 and 43 are turned on, so that 100 V AC supplied to the power receiving terminals 1a and 1b is applied to the motor 41. Motor 41
Starts rotating, and the cam 51 rotates counterclockwise as indicated by the arrow Y in the figure. With the rotation of the cam 51, the opening / closing rod 52 is moved upward as shown by the arrow Z,
The protrusion 52a is separated from the movable piece of the microswitch 43, and the microswitch 43 is turned off. At this time,
Since the movable piece of the micro switch 42 is pushed up by the cam 51, the micro switch 42 is in the ON state, and the motor 41 continues to rotate. The opening / closing rod 52 pushes the opening / closing lever 16 completely, and
Reaches the closed position, the movable piece of the micro switch 42 fits into the notch 51a of the cam 51, and the micro switch 42 is turned off. Thereby, the power supply to the motor 41 is stopped, and the circuit breaker is restored to the state before the cutoff.

(2) Operation at the time of overcurrent It is assumed that a failure occurs in the communication device 60 connected to the terminals 14a and 14b on the load side of the earth leakage breaker 10 and a load current of, for example, 30 A flows. Power receiving terminal 1b and earth leakage breaker 10
Since an overcurrent exceeding the rated current flows through the power supply line 1 between the power supply line 1 and the terminal 11b, a large current flows on the secondary side of the current transformer 21 of the overcurrent detection unit 20, and the output voltage of the rectifier circuit 22 Becomes 8 V or more. The output voltage of the rectifier circuit 22 is supplied to a constant voltage circuit 23, and a stable voltage of 5 V is output from the constant voltage circuit 23 and supplied as a power supply voltage of a voltage comparator 24. The output voltage of the constant voltage circuit 23 is supplied to a resistor 27 and a Zener diode 28, and the Zener voltage of the Zener diode 28 is supplied as a reference voltage to a negative input terminal of a voltage comparator 24. Further, the output voltage of the rectifier circuit 22 is divided by the resistors 25 and 26 and applied to the + input terminal of the voltage comparator 24. Since the load current exceeds the rated current, the output voltage of the rectifier circuit 22 becomes higher than a predetermined voltage.
An “H” overcurrent detection signal is output.

When an "H" overcurrent detection signal is supplied from the voltage comparator 24, the photo switch 31 is turned on,
The power receiving terminals 1a and 1b are connected to the relay coil 32a of the relay 32.
Current flows from the Thereby, the make contact 32b is turned on and the break contact 32c is turned off. When the make contact 32b is turned on, the relay 32 is in a self-holding state, and the break contact 32c is kept off regardless of the on / off state of the photoswitch 31.
On the other hand, in the earth leakage breaker 10, the bimetal provided in the current path warps due to heat due to overcurrent exceeding the rated value.
Within minutes, the switches 12a and 12b are opened, and the power supply to the communication device 60 is cut off.

When the earth leakage breaker 10 is cut off and the lever 16 moves to the open position, the opening / closing rod 52 of the mechanism 50 connected to the lever 16 is moved downward as shown by the arrow X in the figure. . Thereby, the micro switch 4
2, 43 are turned on. However, the break contact 32c connected in series to these microswitches 42, 43
Is kept off, power is not supplied to the motor 41, and the motor 41 remains stopped.
For this reason, the earth leakage breaker 10 is not automatically restored, but is kept in a cut-off state. To restore the earth leakage breaker 10, a worker checks the state of the communication device 60 at the site,
After removing the cause of the failure, the reset switch 33 may be pressed to release the self-holding state of the relay 32. As a result, the break contact 32c is restored and turned on, power is supplied to the motor 41, and the drive unit 40 and the mechanism unit 50 restore the lever 16 to the closed position.

As described above, the circuit breaker of the present embodiment has the following effects (i) to (iii). (I) Since the drive unit 40 and the mechanism 50 for restoring the lever 16 for opening and closing the earth leakage breaker 10 are provided, the earth leakage breaker 10 can be automatically restored without manual operation. (Ii) an overcurrent detection unit 20 that monitors the magnitude of the load current and detects an overcurrent, and a signal holding unit 30 that holds the state of the overcurrent and stops the operation of the drive unit 40 in the case of an overcurrent. ing. Accordingly, in the case of an overcurrent due to a failure on the load side, the earth leakage breaker 10 is not turned on again, and is restarted only in the case of a transient earth leakage due to a lightning surge or the like. Accidents can be prevented from spreading. (Iii) The overcurrent detection unit 20 generates a current transformer 21 for detecting a load current, and a power supply of the voltage comparator 24 and a comparison voltage from a current flowing on the secondary side of the current transformer 21. A rectifier circuit 22 and a constant voltage circuit 23 are provided. Thus, there is no need to provide an independent power supply circuit for the voltage comparator 24, so that the circuit configuration is simple and accurate overcurrent detection can be performed.

Second Embodiment FIG. 3 is a perspective view of an earth leakage breaker restoring device according to a second embodiment of the present invention. This earth leakage breaker restoration device is shown in FIG.
The earth leakage breaker 10 is removed from the circuit breaker of (1), and the overcurrent detection unit 20, the signal holding unit 30, the drive unit 40, and the mechanism unit 50 are configured. This earth leakage breaker restoring device is provided in addition to the existing earth leakage breaker 10A when it is present, so that the earth leakage breaker 10
When A is activated, it is automatically restored. The configurations of the overcurrent detection unit 20, the signal holding unit 30, the driving unit 40, and the mechanism unit 50 are the same as those in FIG. 1, and have the same functions and effects.

The present invention is not limited to the above embodiment, and various modifications are possible. For example, there are the following modifications (a) to (d). (A) Although the earth leakage breaker 10 has an overcurrent interruption function, it is not always necessary to have the overcurrent interruption function. When the overcurrent breaker is not provided, it is desirable to provide an overcurrent breaker on the power supply side of the earth leakage breaker 10 for safety. (B) The configuration of the overcurrent detection unit 20 is not limited to the configuration shown in FIG. 1, and any configuration may be used as long as the occurrence of the overcurrent can be detected when the load current exceeds a predetermined value. . For example, when the load current is equal to or greater than a predetermined value, the constant voltage circuit 23 and the voltage comparison The device 24 and the like can be deleted. Thereby, for example, when the load current in the normal state is 1A,
When the difference is large and strict detection accuracy is not required, such as when the overcurrent detection is set to 15 A, the configuration can be simplified.

(C) The signal holding section 30 is not limited to the configuration shown in FIG. 1, and may have any configuration as long as it can hold the overcurrent detection signal detected by the overcurrent detection section 20. . For example, using a latch type relay having a permanent magnet or a mechanical latch mechanism, and latching this relay with an overcurrent detection signal given from the overcurrent detection unit 20,
The break contact on the output side may be opened. (D) The drive unit 40 and the mechanism unit 50 are not limited to the configuration of FIG. 1, and the lever 16 of the earth leakage breaker 10 moves to the open position and the signal holding unit 30 does not hold the overcurrent detection signal. In addition, any configuration may be used as long as the lever 16 can be restored from the open position to the closed position. For example, a solenoid coil or the like may be used instead of the motor 41 and the cam 51.

[0028]

As described in detail above, the earth leakage breaker restoring device according to the first aspect of the present invention has the drive unit and the mechanism for restoring the lever for opening and closing the earth leakage breaker.
There is an effect that this earth leakage breaker can be automatically restored without manual restoration operation. Further, it has an overcurrent detection unit that monitors the magnitude of the load current and detects an overcurrent, and a signal holding unit that holds the state of the overcurrent and stops the operation of the driving unit in the case of an overcurrent. Thereby, in the case of an overcurrent due to a failure on the load side, the re-input of the earth leakage breaker is stopped, so that it is possible to prevent the accident from spreading and spreading due to the re-input.

According to the second invention, the overcurrent detection section includes the current transformer for detecting the load current, and the power supply for the voltage comparator and the power supply for the comparison based on the current flowing to the secondary side of the current transformer. It has a rectifier circuit for generating a voltage and a constant voltage circuit. Thus, there is no need to provide an independent power supply circuit for overcurrent detection, and there is an effect that the circuit configuration is simple and overcurrent detection with high accuracy can be performed. According to the third invention, a circuit breaker is configured by combining the earth leakage breaker restoring device of the first or second invention and the earth leakage breaker. Thus, a circuit breaker having the same effect as that of the first or second invention can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a circuit breaker according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an appearance of the circuit breaker of FIG. 1;

FIG. 3 is a perspective view of an earth leakage breaker recovery device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power supply line 10 Leakage breaker 12a, 12b Switch part 13 Differential current transformer 15 Detection part 16 Lever 20 Overcurrent detection part 21 Current transformer 22 Rectifier circuit 23 Constant voltage circuit 24 Voltage comparator 30 Signal holding part 31 Photo switch 32 relay 40 drive unit 41 motor 42, 43 micro switch 50 mechanism unit 51 cam 52 opening / closing rod

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02H 3/08 H02H 3/08 S 3/28 3/28 K (72) Inventor Masaaki Tanaka Shinagawa-ku, Tokyo 4-3-8 Osaki, Sankoshya Co., Ltd. (72) Inventor Chika Okabayashi 4-3-8, Osaki, Shinagawa-ku, Tokyo (72) Shinko Oeda, Inventor 4-81 Osaki, Shinagawa-ku, Tokyo No. 3-8 F-term in Sankosia Co., Ltd. (reference) 5G004 AA01 AB02 BA01 BA03 BA04 CA03 DA01 DC06 DC09 FA02 5G030 AB02 FE30 XX01 XX18 YY15 5G047 AA08 5G058 EE10 EF03 EG15 EH01 EH02

Claims (3)

[Claims] 1. An earth leakage breaker is connected to a circuit opening / closing lever of an earth leakage breaker, and the earth leakage breaker detects an earth leakage current flowing from a power supply side to a power supply line on a load side and cuts off power supply to a circuit on the load side. A mechanism for moving the lever from the open position to the closed position, and monitoring a load current flowing from the power supply side to the power supply line on the load side, and when the load current exceeds a predetermined value. An overcurrent detection unit that detects this and outputs an overcurrent detection signal; a signal holding unit that holds the overcurrent detection signal output from the overcurrent detection unit; and the leakage breaker operates to activate the lever. A driving unit that drives the mechanism unit to return the lever from the open position to the closed position if the overcurrent detection signal is not held in the signal holding unit when the lever is moved to the open position. An earth leakage breaker recovery device characterized by the following. 2. The current transformer for outputting a secondary current according to a primary current flowing from the power supply side to a power supply line on the load side, and a rectifier for a secondary current of the current transformer. A rectifier circuit that generates a DC voltage by generating a constant power supply voltage from the DC voltage when the DC voltage generated by the rectifier circuit exceeds a required voltage; A voltage comparison circuit that receives a power supply voltage generated by a voltage circuit, compares the DC voltage generated by the rectifier circuit with a reference voltage, and outputs the overcurrent detection signal when the DC voltage exceeds the reference voltage. A photo switch that converts an overcurrent detection signal output from the voltage comparison circuit into an optical signal, and controls a conduction state of a semiconductor switch by the optical signal; Connect in series Relay coil,
2. A circuit breaker according to claim 1, further comprising a relay having a relay contact which is drawn by a current flowing through said relay coil when said photo switch is turned on to form a self-holding circuit. Recovery device. 3. A switch unit for detecting a leakage current flowing in a circuit on a load side and interrupting power supply to the circuit on the load side.
A circuit breaker comprising: a circuit breaker having a circuit opening / closing lever for restoring the switch section from outside; and a circuit breaker recovery device according to claim 1 or 2.