JP2005327666A - Ground fault interrupter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ground fault interrupter of a simple structure capable of setting a forced high-speed operation when a detection sensitivity is set from a low sensitivity to a high sensitivity. <P>SOLUTION: With the ground fault interrupter 100, when a sensitivity interchange setting part 120 is set at a high sensitivity (30 mA), a time-delay interchange setting part 150 is instantaneously set to a high-speed operation without time delay through a forced high-speed setting part 170. When power leak is detected with such a ground fault interrupter 100, the time-delay interchange setting part 150 inputs drive voltage signals from a leakage detection part 140, and at the same time, outputs the drive voltage signals to a tripping device 160, so that the tripping device 160 drives a switching mechanism of a main circuit contact not illustrated to open a main circuit. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a leakage breaker having an overcurrent protection and a ground fault current protection function applied to a low voltage distribution system.

An earth leakage circuit breaker for preventing an accident due to the occurrence of an earth leakage in an AC circuit is widely used. Some of these earth leakage breakers are known to be capable of switching the sensitivity current, which is the value of the earth leakage current for performing the breaking operation, or switching the delay time, which is the set value of the delay operation time. .
Conventional technologies of this type of earth leakage breaker are roughly classified into domestic type earth leakage breakers and foreign type earth leakage breakers. First, a domestic type earth leakage breaker will be described with reference to the drawings. FIG. 5 is a block diagram of a domestic earth leakage breaker 10 of the prior art. The earth leakage breaker 10 includes a zero-phase current transformer 11, a sensitivity switching setting unit 12, a filter circuit 13, a leakage detection unit 14, a time delay switching setting unit 15, and a tripping device 16.

The earth leakage breaker 10 having such a circuit configuration operates as follows.
In the zero-phase current transformer 11, a main circuit conductor (not shown) is penetrated through the iron core 11a, and a ground fault current generated due to a ground fault or a leakage current (hereinafter referred to as a ground fault current) generated in the load current flowing through the main circuit conductor If these currents are referred to as unbalanced current), a secondary output current signal proportional to the unbalanced current is output from the output winding 11b. This secondary output current signal is input to the sensitivity switching setting unit 12.

  In the sensitivity switching setting section 12, the resistance connected to both ends of the output winding 11b is switched by a setting switch (not shown) to change the resistance value and detect a secondary output current signal from high sensitivity to low sensitivity. The sensitivity can be adjusted step by step. The sensitivity switching range can be set to 100 mA / 300 mA / 500 mA, and the sensitivity can be set from high sensitivity (100 mA) to low sensitivity (500 mA). The sensitivity switching setting unit 12 outputs a detection operation voltage signal by causing the secondary output current signal to flow through the resistance value set by sensitivity adjustment.

The filter circuit 13 outputs a detection operation voltage signal obtained by removing a noise component that causes a malfunction from the detection operation voltage signal output through the sensitivity switching setting unit 12. The detected operation voltage signal is output to the leakage detection unit 14.
The leakage detection unit 14 outputs a drive voltage signal when the voltage value of the detected operation voltage signal exceeds a predetermined threshold value. The drive voltage signal is output to the time delay switching setting unit 15.

Although not shown, the time delay change setting unit 15 includes a time delay change switch that allows setting of a time delay time, a plurality of charging resistors that are switched according to the time delay time set by the time delay change switch, A charging circuit charged with a charging current determined by a resistor is built in. When the time delay is set in advance by the time delay selector switch, the charging resistor corresponding to the time delay is selected and connected to the charging circuit. Shall be. When the driving voltage signal is input to the time delay switching setting unit 15, charging to the charging circuit starts. During the charging period that coincides with the time delay time, the output from the charging circuit does not become a predetermined voltage, and the time delay is set. After the elapse of time, the driving voltage signal that has finished charging and has reached a predetermined voltage is tripped and output to the device 16.
When receiving a drive voltage signal, the trip device 16 drives a main circuit contact opening / closing mechanism (not shown) to open the main circuit.
In this way, the domestic type can set the sensitivity setting and the time delay setting independently.

  Next, a foreign type earth leakage breaker will be described. Foreign type (more specifically, European and American type) earth leakage circuit breakers use a separate circuit breaker protection unit in combination with a circuit breaker for wiring. This point will be described with reference to the drawings. FIG. 6 is a configuration diagram of a foreign earth leakage breaker 20 of the prior art. The earth leakage breaker 20 includes a zero-phase current transformer 21, a sensitivity changeover switch 22, a filter circuit 23, an earth leakage detection unit 24, a charging circuit 25, and a tripping device 26.

The earth leakage breaker 20 having such a circuit configuration operates as follows.
In the zero-phase current transformer 21, when an unbalanced current is included in the load current flowing through the main circuit conductor through a main circuit conductor (not shown) through the iron core 21a, the unbalanced current is output from the output winding 21b. A secondary output current signal proportional to is output. This secondary output current signal is input to the sensitivity switching setting unit 22.

  The sensitivity switching setting unit 22 changes the resistance value by switching the resistors connected to both ends of the output winding 21b with a setting switch (not shown) so that the sensitivity can be adjusted stepwise from high sensitivity to low sensitivity. The sensitivity switching setting unit 22 outputs a detection operation voltage signal by causing the secondary output current signal to flow through a resistor having a resistance value set by sensitivity adjustment. The sensitivity switching setting unit 22 includes first and second circuits for switching sensitivity. The first circuit is a circuit for switching sensitivity from high sensitivity to low sensitivity, and the second circuit is high. This is a circuit for setting a high speed operation when the sensitivity is set, and setting a time delay operation for the others.

For example, as shown in FIG. 6, the sensitivity switching range is 30 mA / 100 mA / 300 mA / 500 mA, and even higher sensitivity (30 mA) than the domestic type earth leakage circuit breaker 10 shown in FIG. Switching is possible. When the first circuit is set to the high sensitivity setting (30 mA), the second circuit is further set to forcibly operate at high speed, and the high sensitivity 30 mA forced high speed signal is supplied to the filter circuit 23 and the leakage detection unit. 24 is skipped and output directly to the time delay switching setting unit 25. The operation of the time delay switching setting unit 25 in this case will be described later.
In summary, in the case of high sensitivity (30 mA), a high-sensitivity 30 mA forced high-speed signal is output to the time delay switching setting unit 25, and in the case of other sensitivity (100 mA / 300 mA / 500 mA), the detection operation voltage signal is sent to the filter circuit 23. Is output.

The filter circuit 23 outputs a detection operation voltage signal obtained by removing a noise component that causes a malfunction from the detection operation voltage signal output through the sensitivity switching setting unit 22. The detected operation voltage signal is output to the leakage detector 24.
The leakage detection unit 24 outputs a drive voltage signal when the voltage value of the detected operation voltage signal exceeds a predetermined threshold value. The drive voltage signal is output to the time delay switching setting unit 25.

Although not shown in the figure, the time delay change setting unit 25 includes a time delay change switch that allows setting of a time delay time, a plurality of charging resistors that are switched according to the time delay time set by the time delay change switch, A charging circuit charged with a charging current determined by a resistor is built in. When the time delay is set in advance by the time delay selector switch, the charging resistor corresponding to the time delay is selected and connected to the charging circuit. Shall be. When the driving voltage signal is input to the time delay switching setting unit 25, charging to the charging circuit starts. During the charging period that coincides with the time delay time, the output from the charging circuit does not become a predetermined voltage, and the time delay is set. After the elapse of time, the driving voltage signal that has finished charging and has reached a predetermined voltage is tripped and output to the device 26. When the high-sensitivity 30 mA forced high-speed signal described above is input, the time delay switching setting unit 25 immediately outputs it as a drive voltage signal to the trip device 26.
The tripping device 26 opens a main circuit by driving an opening / closing mechanism portion of a main circuit contact (not shown) when a driving voltage signal is inputted.
Even if the foreign type is set to be delayed, if it is set to high sensitivity, it is forced to operate at high speed.

As an example of a domestic type earth leakage breaker, the invention disclosed in Patent Document 1 (title of the invention: earth leakage breaker) is known. According to Patent Document 1, an earth leakage circuit breaker that performs both sensitivity current switching and time switching by a mechanical structure is disclosed.
As another example of a domestic type earth leakage breaker, an invention disclosed in Patent Document 2 (title of the invention: earth leakage breaker) is known. According to Patent Document 2, an earth leakage breaker that performs both sensitivity current switching and time switching by a switch is disclosed.

JP 7-141979 A (paragraph numbers 0009 to 0012, FIGS. 1 to 4) Japanese Utility Model Publication No. 62-82546 (Specification, page 13, line 10 to page 14, line 2, FIG. 2)

The domestic earth leakage circuit breaker 10 shown in FIG. 5 has a structure including the sensitivity switching setting unit 12 and the time delay switching setting unit 15 as one body. It wasn't.
Therefore, like the foreign earth leakage breaker 20 in FIG. 6, it has a setting function that can select high speed operation and time delay operation and can be set from high sensitivity to low sensitivity. Although there is a demand for an earth leakage circuit breaker that is forcibly set to a high-speed operation even when the extended operation is set, in the conventional earth leakage circuit breaker 20 shown in FIG. Since the circuit is included, there is a problem that a large installation space is required and the cost is high.
Further, in the pattern wiring connecting the sensitivity switching setting unit 22 and the time delay switching setting unit 25 in the foreign earth leakage breaker 20 of FIG. 6, a high sensitivity 30 mA forced high speed signal, that is, a signal having a small amplitude passes. Because of this, noise countermeasures are necessary because it is easily affected by noise, and there is a problem that the wiring pattern becomes complicated.

  Therefore, the present invention has been made in view of the above-described problems, and an object of the present invention is to forcibly set a high-speed operation when the detection sensitivity is set from low sensitivity to high sensitivity, and to have a simple configuration. It is to provide an earth leakage breaker.

In order to solve the above problems, an earth leakage breaker according to claim 1 of the present invention provides:
A zero-phase current transformer that outputs a secondary output current signal proportional to the unbalanced current contained in the load current of the main circuit conductor penetrating;
A sensitivity switching setting unit that can adjust the sensitivity from high sensitivity to low sensitivity, and causes a secondary output current signal to flow through a resistance value set by sensitivity adjustment to output a detection operation voltage signal;
A filter circuit that outputs a detection operation voltage signal obtained by removing a noise component from the detection operation voltage signal output from the sensitivity switching setting unit;
When the voltage value of the detected operation voltage signal exceeds a predetermined threshold, a leakage detection unit that outputs a drive voltage signal;
It is possible to set high-speed operation for immediate operation or time-delayed operation for which a time delay elapses. In high-speed operation, it can be set immediately after a drive voltage signal is input or in time-delayed operation. A time delay switching setting unit that outputs a drive voltage signal after the time delay time has elapsed,
A tripping device that opens the main circuit by driving the switching mechanism of the main circuit contact when a driving voltage signal is input;
Mechanically linked with the sensitivity switching setting unit, the sensitivity switching setting unit is set to high sensitivity, and at the same time, the forced switching setting unit is set to high speed operation,
It is characterized by providing.

An earth leakage breaker according to claim 2 of the present invention is
The earth leakage breaker according to claim 1, wherein
The time delay switching setting unit is
A high-speed conduction unit that directly connects the leakage detection unit and the tripping device;
A time delay changeover switch that enables setting of the time delay time,
A plurality of charging resistors that are switched according to the time delay set by the time delay switch,
A charging circuit charged with a charging current determined by these charging resistors;
With
When the sensitivity switching setting unit is set to high sensitivity, the high-speed conduction unit is selected by the signal from the forced high-speed setting unit, and the drive voltage signal output from the leakage detection unit is immediately tripped and output to the device. When the sensitivity switching setting unit is set to other than high sensitivity, the charging current obtained by applying the drive voltage signal output by the leakage detection unit to the charging resistor set by the time delay switching switch by the signal from the forced high speed setting unit Thus, after the charging circuit is charged for a time-delayed time, the time-delay operation is performed in which the drive voltage signal is tripped and output to the device.

An earth leakage breaker according to claim 3 of the present invention is
A zero-phase current transformer that outputs a secondary output current signal proportional to the unbalanced current contained in the load current of the main circuit conductor penetrating;
A sensitivity switching setting unit that can adjust the sensitivity from high sensitivity to low sensitivity, and causes a secondary output current signal to flow through a resistance value set by sensitivity adjustment to output a detection operation voltage signal;
A filter circuit that outputs a detection operation voltage signal obtained by removing a noise component from the detection operation voltage signal output from the sensitivity switching setting unit;
It is possible to set either high-speed operation that operates immediately or time-delayed operation that causes a time delay, and if the voltage value of the detection operation voltage signal exceeds a predetermined threshold, An earth leakage detector that outputs a drive voltage signal immediately after a detection operation voltage signal is input, or after a preset time delay time has elapsed during time delay operation,
A tripping device that opens the main circuit by operating to drive the switching mechanism of the main circuit contact when a driving voltage signal is input;
A time delay switching setting unit for setting whether to operate the leakage detection unit at a high speed or a time delay by a signal output;
A forced high-speed setting unit that is mechanically interlocked with the sensitivity switching setting unit, sets the sensitivity switching setting unit to high sensitivity, and simultaneously sets the time delay switching setting unit to output a signal for high-speed operation,
It is characterized by providing.

Moreover, the earth leakage breaker of the invention according to claim 4 of the present invention is
The earth leakage breaker according to claim 3,
When the sensitivity switching setting unit is set to high sensitivity, the time delay switching setting unit outputs a signal output for high speed operation to the leakage detection unit by a signal from the forced high speed setting unit, and this leakage detection unit exceeds the threshold value. When the detection operation voltage signal is input, the drive voltage signal is immediately tripped and output to the device, and when the sensitivity switching setting unit is set to other than high sensitivity, the time delay switching is performed by a signal from the forced high speed setting unit. The setting unit outputs a signal output for time delay operation to the leakage detection unit, and when this leakage detection unit inputs a detection operation voltage signal exceeding a threshold value, the drive voltage signal is tripped after the set delay time has elapsed. It is characterized by a time-delay operation that outputs to

An earth leakage breaker according to claim 5 of the present invention is
In the earth-leakage circuit breaker as described in any one of Claims 1-4,
The forced high speed setting unit is a push button type forced high speed switch,
The sensitivity switching setting unit
A slide switch for sensitivity switching that sets the sensitivity according to the position by slide operation,
A sensitivity switching switch cover for moving the sensitivity switching slide switch;
A switch cover extension for sensitivity switching that connects to the switch cover for sensitivity switching and presses or releases the push button type forced high speed switch depending on the position,
With
When the sensitivity switching switch is slid to the high sensitivity side by operating the sensitivity switching switch cover, the sensitivity switching switch cover extension moves and the push button type forced high speed switch is pressed or released to increase the speed. It is set to operation.

  According to the present invention as described above, when the detection sensitivity is set from low sensitivity to high sensitivity, it is possible to provide an earth leakage circuit breaker that is set to forcibly operate at high speed. In addition, by adopting the forced high-speed setting unit, the sensitivity switching setting unit is only one circuit and miniaturization is realized, and the wiring pattern connecting the sensitivity switching setting unit and the time delay switching setting unit is eliminated, and the whole Therefore, the earth leakage breaker having a simple configuration as a whole can be provided.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of an earth leakage circuit breaker 100 according to the present embodiment. The earth leakage breaker 100 includes a zero-phase current transformer 110, a sensitivity switching setting unit 120, a filter circuit 130, an earth leakage detection unit 140, a time delay switching setting unit 150, a tripping device 160, and a forced high speed setting unit. 170. Although the earth leakage breaker 100 of this form has a point which overlaps with a prior art, it demonstrates again for convenience of explanation.

The earth leakage breaker 100 having such a circuit configuration operates as follows.
In the zero-phase current transformer 110, if a main circuit conductor (not shown) passes through the iron core 110a and an unbalanced current is included in the load current flowing through the main circuit conductor, the unbalanced current is output from the output winding 110b. A secondary output current signal proportional to is output. This secondary output current signal is input to the sensitivity switching setting unit 120.

  In the sensitivity switching setting section 120, the resistance connected to both ends of the output winding 110b is switched by a setting switch (not shown) so that the resistance value can be changed to adjust the sensitivity step by step from high sensitivity to low sensitivity. The secondary output current signal is supplied to the resistance value set by the sensitivity adjustment, and the detection operation voltage signal is output. The sensitivity switching setting unit 120 can perform sensitivity switching from high sensitivity to low sensitivity. As shown in FIG. 1, the sensitivity switching range can be set in steps of 30 mA / 100 mA / 300 mA / 500 mA. is there.

The filter circuit 130 outputs a detection operation voltage signal obtained by removing a noise component that causes a malfunction from the detection operation voltage signal output through the sensitivity switching setting unit 120. The detected operation voltage signal is output to leakage detection unit 140.
The leakage detection unit 140 outputs a drive voltage signal when the voltage value of the detected operation voltage signal exceeds a predetermined threshold value. This drive voltage signal is output to the time delay switching setting unit 150.

Although not shown, the time delay change setting unit 150 includes a time delay change switch that enables setting of a time delay time, a plurality of charging resistors that are switched according to the time delay time set by the time delay change switch, It has a built-in charging circuit (specifically, a capacitor) that is charged with a charging current determined by a resistor, and corresponds to the time delay when the time delay is set in advance by the time delay selector switch. It is assumed that the charging resistor is selected and connected to the charging circuit. When a driving voltage signal is input to such a time delay switching setting unit 150 during the time delay operation, charging to the charging circuit starts. During the charging period that coincides with the time delay time, the output from the charging circuit becomes a predetermined voltage. Instead, the driving voltage signal that has reached the predetermined voltage after the completion of the charging time is tripped and output to the device 160.
In addition, the time delay switching setting unit 150 is provided with a high-speed conduction unit that directly connects the leakage detection unit 140 and the tripping device 160. As will be described later, the time delay switching setting unit 150 is selected only by the push button type forced high-speed switch 171 during high-speed operation. The
The tripping device 160 opens a main circuit by driving an opening / closing mechanism portion (not shown) of a main circuit contact when a driving voltage signal of either a time delay operation or a high speed operation is input.

  In such an earth leakage breaker 100, as shown in FIG. 1, the sensitivity switching range of the sensitivity switching setting unit 120 is set to 30 mA / 100 mA / 300 mA / 500 mA in stages by operating the mechanical sensitivity switching switch. Is possible. Then, a forced high-speed setting unit 170 that is mechanically linked with the sensitivity switching setting unit 120 is newly provided. When the sensitivity switching setting unit 120 is set to a high sensitivity (30 mA), the time delay switching setting unit 150 can be used. Regardless of whether or not such a setting is made, the setting in the forced high speed setting unit 170 is prioritized and the high speed operation is forcibly set.

  The mechanical structure of the sensitivity switching setting unit 120, the time delay switching setting unit 150, and the forced high speed setting unit 170 will be described. FIG. 2 is an explanatory diagram of the mechanical interlocking structure of the sensitivity switching setting unit 120, the time delay switching setting unit 150, and the forced high speed setting unit 170, FIG. 2 (a) is an exploded view, and FIG. 2 (b) is an assembly structure diagram. It is. FIG. 3 is an explanatory diagram of the operation of the mechanical interlocking structure of the sensitivity switching setting unit 120, the time delay switching setting unit 150, and the forced high speed setting unit 170, and FIG. (B) is a diagram showing the release of the switch.

  The mechanical interlocking structure of the sensitivity switching setting unit 120, the time delay switching setting unit 150, and the forced high speed setting unit 170 is as shown in FIGS. 2 (a) and 2 (b). The sensitivity switching setting unit 120 includes a sensitivity switching slide switch 121, a sensitivity switching switch cover 122, and a sensitivity switching switch cover extension 123. The time delay switching setting unit 150 includes a time delay switching slide switch 151 and a time delay switching switch cover 152. The forced high speed setting unit 170 includes a push button type forced high speed switch 171. The sensitivity switching slide switch 121, the time delay switching slide 151, and the push button type forced high speed switch 171 are fixed on the printed wiring board 180 and electrically connected to a pattern wiring (not shown).

As shown in FIG. 2B, a sensitivity switching switch cover 122 is provided above the sensitivity switching slide switch 121. When the sensitivity switching switch cover 122 is operated, the sensitivity switching slide switch 121 moves. The sensitivity switching switch cover 122 is configured so that the sensitivity switching switch cover extension 123 is mechanically integrated. The sensitivity switching switch cover extension 123 moves in the same direction as the sensitivity switching switch cover 122 moves. Move to.
A time delay switching switch cover 152 is also provided above the time delay switching slide switch 151. When the time delay switching switch cover 152 is operated, the time delay switching slide switch 151 also moves.
The sensitivity switching switch cover 122 and the transition delay switching switch cover 152 appear outside as an operation unit of the leakage breaker 100, and are arranged at positions that are easy to operate from the outside.

  Next, the operation of the push button type forced high-speed switch 171 will be described with reference to FIGS. When setting the low sensitivity, as shown in FIG. 3A, the sensitivity switching switch cover 122 is operated to move the sensitivity switching slide switch 121 in the arrow B direction. In this case, the sensitivity switching switch cover extension 123 also moves in the same direction, but the push button type forced high-speed switch 171 is pushed down by the bending portion 123a and gradually descends downward, and finally FIG. As shown in a), it is in a fully depressed state. When the push button type forced high-speed switch 171 is pressed, a path through the charging resistor and the charging circuit is selected by the time delay switching setting unit 150, and the drive voltage signal output from the leakage detecting unit 140 is When charging current is applied to the charging resistor and the charging current is input to the charging circuit, charging to the charging circuit is started. In order to output to the tripping device 160, a time delay operation is performed.

  However, when setting the high sensitivity, as shown in FIG. 3B, the sensitivity switching switch cover 122 is operated to move the sensitivity switching slide switch 121 in the arrow C direction. In this case, the sensitivity switching switch cover extension 123 also moves in the same direction, but the push button type forced high-speed switch 171 is released by the bending portion 123a and gradually rises upward, and finally FIG. As shown in b), it is completely released. When the push-button forced high-speed switch 171 is released, the high-speed conduction unit is selected in the time delay switching setting unit 150 and the drive voltage signal output from the leakage detection unit 140 is input to the trip device 160 as it is. To be made. Thereby, high-speed operation is realized.

By adopting such a configuration, the sensitivity switching setting unit 120 becomes a switch with one circuit, and is smaller and less expensive than a sensitivity switching setting unit with two circuits as in the prior art. Further, there is no pattern connecting the sensitivity switching setting unit 120 and the time delay switching setting unit 150, and the wiring pattern is reduced.
Furthermore, since all the circuits pass through the filter circuit 130 and the leakage detection unit 140, the wiring pattern can be omitted also in this respect.

Next, another embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a configuration diagram of an earth leakage breaker 200 of another form. The earth leakage breaker 200 includes a zero-phase current transformer 210, a sensitivity switching setting unit 220, a filter circuit 230, an earth leakage detection unit 240, a time delay switching setting unit 250, a tripping device 260, and a forced high speed setting unit. 270.
The earth leakage breaker 200 of this embodiment is the same as the structure of the earth leakage breaker 100 described above with respect to the zero-phase current transformer 210, the sensitivity switching setting unit 220, the filter circuit 230, and the tripping device 270. The leakage detection unit 240 and the time delay switching setting unit 250 have different functions. These points will be explained mainly.

  The leak detection unit 240 can be set to a high-speed operation that operates immediately with a time delay of 0, or a time delay that can be set to operate after a time delay has elapsed. Built-in timer, and when the voltage value of the detection operation voltage signal exceeds a predetermined threshold, at the time of high-speed operation, immediately after the detection operation voltage signal is input or at the time of delay operation Then, the drive voltage signal is output after elapse of a preset time delay time. This drive voltage signal is output to the trip device 260.

  Although not shown, the time delay change setting unit 250 has a time delay change switch that allows setting of the time delay time, and the time delay time is set beforehand by the time delay change switch (in the case of 0, high speed operation is performed). When set, the time delay time is set by transmitting a plurality of high or low binary signals (3 bits in FIG. 4) to the time delay timer of the leakage detection unit 240. The selection of the high-speed conduction unit is performed when a signal is input from the forced high-speed setting unit 270. For example, an all high binary signal or an all low binary signal is transmitted from the time delay switching setting unit 250. Shall be output.

For example, when selecting a sensitivity other than high sensitivity, the push button type forced high-speed switch 171 is pressed as shown in FIG. In this case, in order to continue outputting a High or Low binary signal indicating the time delay time set in advance by the time delay changeover switch in the time delay changeover setting unit 250 to the time delay timer of the leakage detection unit 240, the time delay operation is performed. Type earth leakage breaker.
On the other hand, when the sensitivity is selected as high sensitivity, the push button type forced high-speed switch 171 is released as shown in FIG. In this case, for example, when the time delay switching setting unit 250 is connected to the ground potential and is output to the time delay timer of the leak detection unit 240 as all low binary signals, the time delay timer of the leak detection unit 240 sets the time delay time. It can be set to 0 to provide a high-speed operation type earth leakage breaker 200. A circuit configuration is also possible in which when the push button type forced high-speed switch 171 is released, the time delay timer sets the time delay time 0 as a high binary signal for high speed operation. Such an earth leakage breaker 200 can also achieve the object of the present invention.

The earth leakage breakers 100 and 200 of the present invention have been described above. The forced high speed setting units 170 and 270 shown in FIGS. 3 and 4 perform a time delay operation when the push button type forced high speed switch 171 is pressed, and perform a high speed operation when the push button type forced high speed switch 171 is released. It was explained that
However, the push button type forced high speed switch 171 is operated so that a high speed operation is performed when the push button type forced high speed switch 171 is pressed and a time delay operation is performed when the push button type forced high speed switch 171 is released. The position and structure of the sensitivity switching switch cover extension 123 may be changed. These structures are appropriately selected.

It is a block diagram of the earth-leakage circuit breaker of the best form for implementing this invention. It is explanatory drawing of the mechanical interlocking | linkage structure of a sensitivity switching setting part, a time delay switching setting part, and a forced high speed setting part, Fig.2 (a) is an exploded view, FIG.2 (b) is an assembly structure figure. It is explanatory drawing of operation | movement of the mechanical interlocking structure of a sensitivity switching setting part, a time delay switching setting part, and a forced high speed setting part, FIG. 3 (a) is a figure which shows pressing of a switch, FIG.3 (b) is release of a switch. FIG. It is a block diagram of the earth-leakage circuit breaker of another form. It is a block diagram of the domestic type earth-leakage circuit breaker of a prior art. It is a block diagram of the foreign-type earth-leakage circuit breaker of a prior art.

Explanation of symbols

100: Earth leakage breaker 110: Zero-phase current transformer 110a: Iron core 110b: Output winding 120: Sensitivity switching setting unit 121: Sensitivity switching slide switch 122: Sensitivity switching switch cover 123: Sensitivity switching switch cover extension 123a : Bending section 130: filter circuit 140: leakage detection section 150: time delay switching setting section 151: time delay switching slide switch 152: time delay switching switch cover 160: trip device 170: forced high speed setting section 171: push button Forced high-speed switch 180: Printed wiring board 200: Earth leakage breaker 210: Zero phase current transformer 210a: Iron core 210b: Output winding 220: Sensitivity switching setting unit 230: Filter circuit 240: Earth leakage detection unit 250: Time delay switching setting Unit 260: Tripping device 270: Forced high speed setting unit

Claims (5)

A zero-phase current transformer that outputs a secondary output current signal proportional to the unbalanced current contained in the load current of the main circuit conductor penetrating;
A sensitivity switching setting unit that can adjust the sensitivity from high sensitivity to low sensitivity, and causes a secondary output current signal to flow through a resistance value set by sensitivity adjustment to output a detection operation voltage signal;
A filter circuit that outputs a detection operation voltage signal obtained by removing a noise component from the detection operation voltage signal output from the sensitivity switching setting unit;
When the voltage value of the detected operation voltage signal exceeds a predetermined threshold, a leakage detection unit that outputs a drive voltage signal;
It is possible to set high-speed operation for immediate operation or time-delayed operation for which a time delay elapses. In high-speed operation, it can be set immediately after a drive voltage signal is input or in time-delayed operation. A time delay switching setting unit that outputs a drive voltage signal after the time delay time has elapsed,
A tripping device that opens the main circuit by driving the switching mechanism of the main circuit contact when a driving voltage signal is input;
Mechanically linked with the sensitivity switching setting unit, the sensitivity switching setting unit is set to high sensitivity, and at the same time, the forced switching setting unit is set to high speed operation,
An earth leakage circuit breaker comprising: The earth leakage breaker according to claim 1, wherein
The time delay switching setting unit is
A high-speed conduction unit that directly connects the leakage detection unit and the tripping device;
A time delay changeover switch that enables setting of the time delay time,
A plurality of charging resistors that are switched according to the time delay set by the time delay switch,
A charging circuit charged with a charging current determined by these charging resistors;
With
When the sensitivity switching setting unit is set to high sensitivity, the high-speed conduction unit is selected by the signal from the forced high-speed setting unit, and the drive voltage signal output from the leakage detection unit is immediately tripped and output to the device. When the sensitivity switching setting unit is set to other than high sensitivity, the charging current obtained by applying the drive voltage signal output by the leakage detection unit to the charging resistor set by the time delay switching switch by the signal from the forced high speed setting unit Then, after the charging circuit is charged for a time-delayed time, the circuit breaker operates in a time-delayed manner in which the drive voltage signal is tripped and output to the device. A zero-phase current transformer that outputs a secondary output current signal proportional to the unbalanced current contained in the load current of the main circuit conductor penetrating;
A sensitivity switching setting unit that can adjust the sensitivity from high sensitivity to low sensitivity, and causes a secondary output current signal to flow through a resistance value set by sensitivity adjustment to output a detection operation voltage signal;
A filter circuit that outputs a detection operation voltage signal obtained by removing a noise component from the detection operation voltage signal output from the sensitivity switching setting unit;
It is possible to set either high-speed operation that operates immediately or time-delayed operation that causes a time delay, and if the voltage value of the detection operation voltage signal exceeds a predetermined threshold, An earth leakage detector that outputs a drive voltage signal immediately after a detection operation voltage signal is input, or after a preset time delay time has elapsed during time delay operation,
A tripping device that opens the main circuit by operating to drive the switching mechanism of the main circuit contact when a driving voltage signal is input;
A time delay switching setting unit for setting whether to operate the leakage detection unit at a high speed or a time delay by a signal output;
A forced high-speed setting unit that is mechanically interlocked with the sensitivity switching setting unit, sets the sensitivity switching setting unit to high sensitivity, and simultaneously sets the time delay switching setting unit to output a signal for high-speed operation,
An earth leakage circuit breaker comprising: The earth leakage breaker according to claim 3,
When the sensitivity switching setting unit is set to high sensitivity, the time delay switching setting unit outputs a signal output for high speed operation to the leakage detection unit by a signal from the forced high speed setting unit, and this leakage detection unit exceeds the threshold value. When the detection operation voltage signal is input, the drive voltage signal is immediately tripped and output to the device, and when the sensitivity switching setting unit is set to other than high sensitivity, the time delay switching is performed by a signal from the forced high speed setting unit. The setting unit outputs a signal output for time delay operation to the leakage detection unit, and when this leakage detection unit inputs a detection operation voltage signal exceeding a threshold value, the drive voltage signal is tripped after the set delay time has elapsed. The earth leakage circuit breaker is characterized in that the operation is delayed. In the earth-leakage circuit breaker as described in any one of Claims 1-4,
The forced high speed setting unit is a push button type forced high speed switch,
The sensitivity switching setting unit
A slide switch for sensitivity switching that sets the sensitivity according to the position by slide operation,
A sensitivity switching switch cover for moving the sensitivity switching slide switch;
A switch cover extension for sensitivity switching that connects to the switch cover for sensitivity switching and presses or releases the push button type forced high speed switch depending on the position,
With
When the sensitivity switching switch is slid to the high sensitivity side by operating the sensitivity switching switch cover, the sensitivity switching switch cover extension moves and the push button type forced high speed switch is pressed or released to increase the speed. An earth leakage circuit breaker that is set to operate.

Images