JP2012084470A - Earth leakage breaker for distribution board and distribution board system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an earth leakage breaker for distribution board megger test of which can be carried out easily by changing the power supply of a leakage detection circuit from a main circuit in a breaker to an external power supply.SOLUTION: The earth leakage breaker applied to the branch breaker of a distribution board is mounting, on the body case, main circuit contacts, a make/break mechanism of main circuit contacts, an overcurrent tripping device, and a leakage tripping device including a zero-phase current transformer and a leakage detection circuit. The earth leakage breaker is further provided, on the body case 6 thereof, with a power supply terminal 21 dedicated to the leakage detection circuit as a power supply connection means for supplying power externally to the leakage detection circuit 17 after separating the power supply of the leakage detection circuit 17 from the main circuit 20 in the body case.

Description

  The present invention relates to a leakage breaker for a distribution board applied to a branch breaker for residential and store distribution boards, and a distribution board system equipped with the leakage breaker.

  As is well known, indoor low voltage wiring equipment is obliged to be equipped with a distribution board to protect the main line from overcurrent, to prevent electric shock of the wiring, and to prevent fire. As shown in FIG. 4, this distribution board has a main circuit breaker 2, a main bar (bus bar) 3, a branch bar 4, a lighting bar, and an outlet connected to the main line (commercial power) inside the box of the distribution board 1. Each module of the branch breaker 5 connected to the branch bar 4 is divided into load circuits such as motive power.

  The branch breaker 5 includes a circuit breaker (MCCB) with an overcurrent protection function, and an earth leakage breaker (ELCB: Earth Leakage with an overcurrent protection function and a ground fault protection function). Depending on the type of load connected to the branch line, circuit breakers are used for lights, outlet circuits, etc., and circuit breakers are used for equipment and power circuits that may cause electric shock due to electric leakage. Is done.

  A small-capacity branch breaker 5 used in residential lighting distribution boards, etc., is called “agreement type breaker” and its outer dimensions are manufactured in accordance with the standard (JIS standard). Circuit breakers are commonly used. This “agreement-type breaker” is smaller and more compact than standard general-purpose circuit breakers and earth leakage circuit breakers. The detailed internal structure and overcurrent / leakage protection operation are disclosed in, for example, Patent Document 1. Is described in detail.

  That is, the circuit breaker for distribution boards has a configuration in which a main circuit contact, a main circuit contact switching mechanism, and an overcurrent tripping device are mounted inside a molded resin body case. On the other hand, the earth leakage circuit breaker has a main body case with the same external dimensions as the circuit breaker for wiring, as well as an overcurrent protection functional part similar to the circuit breaker for wiring, and a leakage current tripping device including a zero-phase current transformer and a circuit for detecting leakage It becomes the composition which combined.

  Next, taking an example of a single-phase bipolar earth leakage breaker (ELCB) as an example, an outline view and an equivalent circuit diagram of the conventional product are shown in FIGS. 5 (a) and 5 (b). First, in FIG. 5A, 6 is a molded resin body case, 7 and 8 are power supply side terminals, 9 and 10 are load side terminals, 11 is an opening / closing operation handle, and 12 is a leakage test button. In the equivalent circuit of FIG. 5B, 13 is a leakage test switch linked to the test button 12, 14 is a main circuit contact, 15 is an overcurrent / short-circuit protection element, 16 is a zero-phase current transformer, and 17 is A leakage detection circuit (electronic circuit) 18 is a trip coil of the main circuit contact 14. Here, the leakage detection circuit 17 is connected between the phases of the main circuit 20 inside the circuit breaker via the power line 19, and the interphase voltage (AC) of the main circuit 20 is converted to DC to convert the electronic circuit of the leakage detection circuit 17. I am trying to supply power.

  By the way, it is stipulated that an earth leakage circuit breaker performs a mega test (withstand voltage test) during periodic inspections to check the soundness of the equipment. In this mega test, the main circuit contact 14 of the earth leakage circuit breaker is opened (OFF) and a test voltage is applied between the phases of the main circuit 20 to perform the test. When the mega test is performed while the circuit is connected between the phases of the main circuit 20, there is a risk that the electronic circuit of the leakage detection circuit 17 is destroyed by the application of a high test voltage.

  Therefore, it is necessary to disconnect the power line 19 of the leakage detection circuit 17 from the main circuit 20 prior to the execution of the mega test. However, when a plurality of earth leakage breakers (ELCB) are installed in the panel as the branch breaker 5 of the distribution board (see FIG. 4), the cover of the main body case 6 is opened one by one and the power line 19 Is required to be removed from the main circuit 20, and the work is troublesome.

  On the other hand, for a general-purpose earth leakage breaker with a large amperage frame, the main body case of the earth leakage breaker is provided so that a mega test can be performed without the trouble of disconnecting the power line 19 of the leakage detection circuit 17 from the main circuit 20. The switch for mega test is built in, and the power supply of the leakage detection circuit 17 is disconnected by pressing the button of the switch for mega test. At the same time, the main circuit contact 14 of the circuit breaker is forcibly opened. An earth leakage circuit breaker capable of safely performing a mega test has been proposed prior to the same applicant as the present invention (see, for example, Patent Document 2).

JP-A-10-64402 JP 2007-317361 A

  The above-mentioned “agreement type breaker” (see FIG. 5) has a mega test changeover switch as disclosed in Patent Document 2 because the main body case 6 is restricted to a compact and compact agreement size. There is not enough room to be installed inside the case, and there is currently no commercial leakage breaker with a built-in mega test switch.

  It is possible to use the switch for mega test as an external accessory in combination with the earth leakage breaker of the “contract breaker”. However, as shown in FIG. In the case of arranging 5 in parallel, since the mega test changeover switch of the external accessory occupies space, there is a problem that the space efficiency in the panel is lowered, which is not practical.

  The present invention has been made in view of the above points, and a first object is to change the power source of the leakage detection circuit from the main circuit inside the circuit breaker to an external power source, thereby easily performing the mega test. An object of the present invention is to provide an earth leakage circuit breaker for a distribution board improved so as to be able to cope with it. The second purpose is a distribution board with a new function that can supply and stop power from the outside to the earth leakage detection circuit of each earth leakage breaker for the electricity distribution board with earth leakage breakers arranged in parallel in the board. It is to provide a panel system.

In order to achieve the first object, according to the present invention, a main circuit contact connected to a main circuit, a switching mechanism for the main circuit contact, an overcurrent trip device, a zero-phase current transformer, In the earth leakage breaker equipped with the earth leakage trip device including the earth leakage detection circuit and connected to the power branch line of the distribution board,
The power supply of the leakage detection circuit is separated from the main circuit inside the main body case, and dedicated external power supply connection means for supplying power to the leakage detection circuit from the outside is provided (Claim 1), and the external power supply connection As a specific mode of the means, a power supply terminal dedicated to a leakage detection circuit is provided in the main body case (claim 2).

In order to achieve the second object, according to the distribution board system of the present invention, in the distribution board in which the earth leakage circuit breaker provided with the external power supply connection means as a branch breaker is arranged in parallel in the board, The leakage detection circuit of each leakage breaker is provided with a power supply circuit that collectively supplies and stops power from the outside (Claim 3), and the power supply circuit can be configured in a specific manner as described below. .
(1) One branch breaker installed in the distribution board and connected to the power branch line is used as a power supply switch for the external power supply, and the leakage of each earth leakage breaker installed in the branch breaker load side terminal and panel A power supply cable is wired between the detection circuit and the detection circuit to form a power supply circuit.
(2) An independent external power supply is provided as a power supply for the leakage detection circuit of each earth leakage breaker installed in the distribution board, and a power cable is wired between the external power supply and the leakage detection circuit of each earth leakage breaker Thus, a power feeding circuit is formed (claim 5).
(3) In the distribution board system of (1) or (2) above, route the power cable via the terminal block between the leakage detection circuit of each leakage breaker installed in the distribution board and the external power supply. (Claim 6).

According to the leakage breaker for distribution board and distribution panel system configured as described above, the following effects can be obtained.
(1) After the leakage detection circuit is separated from the main circuit inside the main body case, a power supply terminal dedicated to the leakage detection circuit is provided on the main body case of the circuit breaker as an external power connection means for supplying power from the outside. 2) Therefore, when performing a mega test when checking the earth leakage breaker, there is no need for the troublesome work of disconnecting the power line of the earth leakage detection circuit from the main circuit inside the main body case as in the past. The mega test can be performed safely by disconnecting the external power supply. In addition, this power terminal can be installed in a small space, and the above-mentioned “agreement type breaker” can be additionally installed in the main body case without any restrictions.

  In addition, by always disconnecting the external power supply of the leakage detection circuit, it is possible to invalidate the ground fault protection function of the leakage breaker and to operate the leakage breaker as a wiring breaker. As a result, the user can use the protection function of the branch breaker (earth leakage breaker) installed on the distribution board according to the type of load (light load, power load).

  On the other hand, for the above-mentioned earth leakage breakers connected in parallel to the power distribution line of the distribution board, a power supply circuit that supplies and stops power from the outside to the earth leakage detection circuit of each earth leakage breaker According to the distribution board system of the present invention (claims 3 to 6), even when the mega test is simultaneously performed for each branch breaker in the distribution board, the external power source for the leakage detection circuit of each leakage breaker The mega test can be performed quickly and neatly by disconnecting all together. In addition, when changing the type of load connected to the branch circuit, disable the leakage protection function of the leakage breaker installed in the distribution board as necessary, and operate the leakage breaker as a wiring breaker. You can also.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the earth leakage circuit breaker for distribution boards by the Example of this invention, Comprising: (a), (b) is a front view, a side view, respectively, (c) is an equivalent circuit schematic. It is a block diagram of the distribution board system by the Example of this invention. It is a block diagram of the distribution board system of the Example different from FIG. It is a standard block diagram of a distribution board. It is a block diagram of the conventional earth-leakage circuit breaker applied to the branch breaker of the distribution board of FIG. 4 as a "contract type breaker", (a) is an external perspective view, (b) is an equivalent circuit diagram.

Hereinafter, embodiments of the present invention will be described based on examples shown in FIGS. In the drawing of the embodiment, parts corresponding to those in FIG. 4 and FIG.
First, an earth leakage breaker (ELCB) for a distribution board corresponding to claims 1 and 2 of the present invention is shown in FIGS. In this embodiment, as shown in the equivalent circuit of FIG. 1C, the power line 19 of the leakage detection circuit 17 is separated from the main circuit 20 inside the circuit breaker, and then an external power source (not shown) is connected exclusively. Power supply terminal 21 is provided. For example, a pin / jack-type connector is used as the power terminal 21, and as shown in FIGS. 1 (a) and 1 (b), power-side terminals 7 and 8 disposed at both ends of the main body case 6, and a load-side terminal 9. , 10 and arranged alongside the operation handle 11 on the front surface of the main body case 6.

  As described above, when the leakage test circuit 17 is disconnected from the main circuit 20 inside the circuit breaker and then the power is supplied from the outside via the power terminal 21 for external connection, the mega test is performed. Can safely perform a mega test simply by disconnecting the external power supply connected to the power supply terminal 21. Therefore, unlike the conventional earth leakage circuit breaker shown in FIG. 5, it is not necessary to remove the power line 19 of the earth leakage detection circuit 17 from the main circuit 20 during the mega test, and the workability can be greatly improved.

Further, by always disconnecting the external power source connected to the power terminal 21, it is possible to invalidate the leakage protection function of the leakage breaker and operate as a circuit breaker.
In other words, when a power load is connected to the branch line of the distribution board and power is supplied, some users check the presence or absence of leakage in the distribution circuit and the magnitude of the leakage current at the beginning of distribution facility operation using a leakage breaker. After that, the user who replaces the earth leakage breaker with a circuit breaker in order to prevent the earth leakage breaker from operating unnecessarily due to a light leakage current with no risk of electric shock and the load operation being stopped. There are also many. If the leakage breaker of the illustrated embodiment is employed in such a case, the leakage breaker can be used as it is as a wiring breaker simply by disconnecting the external power supply of the leakage detection circuit 17. Will increase. Note that if the external power supply of the leakage detection circuit is returned to the power supply state from the stop, the leakage protection function of the leakage breaker becomes effective.

  Next, an embodiment of a distribution board system according to the present invention is shown in FIGS. 2 is a distribution board system corresponding to claims 3 and 4 of the present invention, and FIG. 3 is a configuration diagram of the distribution board system in which the requirements of claims 5 and 6 are added to the configuration of FIG.

  In the distribution board system of this embodiment, a plurality of branch breakers 5 are arranged and connected to the main breaker 2 of the distribution board 1 in the left and right rows via the main bar 3 and the branch bar 4 as in FIG. ing. In the illustrated embodiment, a plurality of wiring circuit breakers 5 (MCCB) are vertically arranged in the right column in the panel, and a plurality of wiring circuit breakers 5-1 (MCCB) are arranged in the left column. The earth leakage breakers 5 (ELCB) are arranged vertically and connect the power supply side terminals of each branch breaker to the corresponding branch bar 4. Then, the load circuit of the distribution facility that supplies power from the distribution board 1 supplies power through the wiring breakers 5 (MCCB) in the right column in the panel and the leakage breakers (ELCB) in the left column.

  Here, each earth leakage breaker 5 (ELCB) arranged in the left column in the panel adopts the earth leakage breaker 5 (ELCB) with the power supply terminal described in the embodiment of FIG. In addition, the power supply terminal 21 corresponding to the leakage detection circuit 17 (see FIG. 1 (c)) of the leakage breaker 5 (ELCB) is installed in the uppermost row on the left column in the panel via the power cable 22. It is connected to the load side terminal of the device 5-1 (MCCB). Then, using this circuit breaker 5-1 (MCCB) as a power switch, the power supply is supplied to the leakage detection circuit 17 of each leakage breaker 5 (ELCB) from the power supply branch line in the panel and is controlled to stop. I have to.

  In the distribution board system of the embodiment shown in FIG. 3, an external power supply 23 (for example, a battery) that is independent of the power supply of the distribution board 1 is used as the power supply of the leakage detection circuit 17 of each leakage breaker 5 (ELCB). DC power source, etc.) and terminal block 24 are additionally provided, and the circuit breaker 5-1 (MCCB) in the panel is connected to the leakage detection circuit of each circuit breaker 5 (ELCB) installed in the panel. Alternatively, the power is supplied and stopped from any one of the external power sources 23 in a lump. Reference numeral 23a denotes an output switch of the external power source 23.

  According to the above distribution board system, the power supply is collectively supplied to the leakage detection circuit 17 (see FIG. 1 (c)) for each leakage breaker 5 (ELCB) installed in the board, and the stop control is performed. As a result, it is possible to greatly improve the workability when the mega test is performed compared to the conventional case. In addition, by stopping the power supply of the power supply in units of distribution boards, the leakage protection function of each leakage breaker 5 (ELCB) installed in the panel is invalidated and the leakage breaker is operated as a wiring breaker. You can also.

1 distribution board 2 main breaker 3 main bar 4 branch bar 5 branch breaker 5 (MCCB) circuit breaker 5 (ELCB) earth leakage breaker 5-1 (MCCB) circuit breaker 6 used as power switch 6 body case 7 , 8 Power supply side terminal 9,10 Load side terminal 14 Main circuit contact 16 Zero phase current transformer 17 Leakage detection circuit 19 Power line 20 Main circuit 21 Power supply terminal 22 Power supply cable 23 External power supply 24 Terminal block

Claims (6)

An earth leakage circuit breaker applied to a branch breaker of a distribution board, which is connected to a main circuit case, a main circuit contact connected to the main circuit, a switching mechanism for the main circuit contact, an overcurrent trip device, a zero-phase current transformer, and an electric leakage In what is connected to the power branch line of the distribution board with the leakage trip device including the detection circuit
An earth leakage breaker for a distribution board, comprising a power connection means for supplying power to the leakage detection circuit from outside after separating the power supply of the leakage detection circuit from a main circuit inside the main body case.   The earth leakage breaker for a distribution board according to claim 1, wherein a power terminal dedicated to the earth leakage detection circuit is provided in the main body case as a power connection means of the earth leakage detection circuit for supplying power from outside. Panel earth leakage breaker.   Supplying power to the earth leakage detection circuit of each earth leakage breaker collectively from the outside to the earth leakage breaker according to claim 1 connected to the power branch line of the distribution board and arranged in parallel in the board. A distribution board system characterized by comprising a circuit.   4. The distribution board system according to claim 3, wherein one branch breaker installed in the distribution board and connected to the power branch line is used as a power supply switch for an external power source, and the load-side terminal of the branch breaker and the panel A distribution board system characterized in that a power supply circuit is formed by wiring a power cable between each earth leakage breaker installed in the circuit and a leakage detection circuit.   4. The distribution board system according to claim 3, further comprising an external power supply as a power supply for supplying power to a leakage detection circuit of each leakage breaker installed in the distribution board, and detecting leakage of the external power supply and each leakage breaker. A distribution board system in which a power supply cable is formed between the circuit and a power supply circuit.   The distribution board system according to claim 5, wherein a power cable is wired between the leakage detection circuit of each leakage breaker installed in the distribution board and an external power source via a terminal block. Distribution board system.