WO1998042001A1 - Earth leakage circuit breaker - Google Patents

Abstract

A low-cost earth leakage circuit breaker which comprises a less number of parts and can be assembled easily. The earth leakage circuit breaker is highly reliable, has the same external size as those of the same class of wiring circuit breakers and can be easily attached to a board. A zero-phase current transformer is provided between the power supply-side terminal and make-and-break contacts of a main circuit from the power supply-side terminals to load side terminals through the make break contacts. An overcurrent detecting means is provided between the make-and-break contacts and load-side terminals of the main circuit.

Description

 Specification

Earth leakage breaker

Technical field

 The present invention relates to a small-sized, low-cost earth leakage circuit breaker having a small number of parts and excellent in assemblability.

Background art

 Examples of conventional circuit breakers include JP-A-5-217486, JP-A-5-217489, and JP-A-6-52777. The circuit breakers disclosed in these publications open and close two switching contacts by the rotation of a movable contact block. In order for this circuit breaker to have the function of an earth leakage breaker, the circuit breaker must be An earth leakage detector and earth leakage trip unit were added on the load side.

 However, in the above-mentioned prior art, no consideration is given to the mounting method of the earth leakage detection unit and the earth leakage trip unit, and the earth leakage detection unit and the earth leakage trip unit are connected to the circuit breaker. Therefore, the external dimensions of the earth leakage breaker are larger than those of the same class. For this reason, when an earth leakage breaker is installed in the control panel or distribution panel (hereafter, panel), there has been a problem in that the dimensions of the panel must be increased. In addition, because the dimensions of the circuit breaker and the earth leakage breaker are not taken into consideration when designing the circuit breaker and the earth leakage breaker in the panel, it is difficult to design the panel. There was a problem.

If a leakage detector and a leakage trip unit are added to the load side of the circuit breaker, the operation handle for opening and closing the main circuit is separated from the center of the external shape of the main body as the leakage breaker. Although it is rarely used, when used in reverse connection, the handle position is not much different from other circuit breakers. There was a problem that it was hard to incorporate into the board and was inconvenient to use.

 In addition, simply configuring the earth leakage breaker by integrating the earth leakage detection unit and earth leakage trip unit, which were conventionally added to the load side, within the housing will cause the operation handle to move from the center of the outer shape of the main unit. It is located at a distance from the inside of the panel and cannot be solved because it is difficult to assemble it and it is not easy to use. In addition, there is a problem that the arc gas at the time of shutoff reaches the leakage detector and causes serious deterioration. I got it.

Disclosure of the invention

 An object of the present invention is to provide an earth leakage breaker that is small in size and can be made the same size as a circuit breaker.

 Another object of the present invention is to provide an earth leakage breaker that is small in size, can be made the same size as a circuit breaker, and has excellent reliability.

 [Means for Solving the Problems]

 The above objectives are to provide a main circuit from the power supply terminal to the load terminal via the switching contact, a switching mechanism for opening and closing the switching contact, and a zero-phase current transformer to prevent leakage from the current flowing through the main circuit. An earth leakage detecting means for detecting, an earth leakage trip device for tripping the switching mechanism by an output of the earth leakage detecting means, and an overcurrent having a current transformer and detecting an overcurrent from a current flowing through the main circuit. Detection means, and an overcurrent trip device that trips the switching mechanism based on the output of the overcurrent detection means, and a zero-phase current transformer is connected between the power supply terminal of the main circuit and the switching contact. This is achieved by an earth leakage breaker provided with a current transformer between the switching contact of the main circuit and the load terminal.

The other objectives are as follows: the main circuit from the power supply terminal to the load terminal via the switching contact; the switching mechanism for opening and closing the switching contact; and the current flowing through the main circuit with the zero-phase current transformer. Leakage detection means for detecting leakage, and leakage detection means A tripping device for tripping the switching mechanism by the output of the overcurrent detection device, an overcurrent detection device having a current transformer and detecting an overcurrent from the current flowing through the main circuit, and an output of the overcurrent detection device. And an overcurrent trip device that trips the switching mechanism.A zero-phase current transformer is installed between the main circuit power supply side terminal and the switching contact, and the main circuit switching contact is connected to the load side terminal. A current transformer, and a shielding means for shielding the arc generated at the switching contact between the switching contact and the zero-phase current transformer. Is achieved.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a side sectional view showing a configuration of an earth leakage breaker according to a first embodiment of the present invention.

FIG. 2 is a plan sectional view showing the configuration of the earth leakage breaker according to the first embodiment of the present invention.

FIG. 3 is a plan view of the earth leakage breaker according to the first embodiment of the present invention.

FIG. 4 is a front view of the vicinity of ZCT from the power supply side of the earth leakage breaker according to the first embodiment of the present invention.

FIG. 5 is an exploded perspective view of a ZCT penetrating portion of a fixed conductor on the power supply side of the earth leakage breaker according to the first embodiment of the present invention.

FIG. 6 is a block diagram showing a circuit configuration of the earth leakage breaker according to the first embodiment of the present invention.

FIG. 7 is a plan sectional view showing a configuration of a modified example of the earth leakage breaker in the first embodiment of the present invention.

 FIG. 8 is a front view of a modification of the earth leakage breaker according to the first embodiment of the present invention as viewed from the power supply side and around the ZCT.

 FIG. 9 is a side sectional view showing a configuration of an earth leakage breaker according to a second embodiment of the present invention.

FIG. 10 is a circuit configuration of an earth leakage breaker according to a second embodiment of the present invention. FIG.

FIG. 11 is a side sectional view showing a configuration of an earth leakage breaker according to a third embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

 An embodiment of the present invention will be described with reference to FIG. 1 to FIG.

 A first embodiment of the present invention will be described with reference to FIGS. Fig. 1 and Fig. 2 show the structure of the earth leakage breaker of this embodiment, Fig. 3 shows the front view, Fig. 4 and Fig. 5 show the zero-phase current transformer mounting part, and Fig. The block diagrams are shown in Fig. 6, respectively. In this embodiment, the leakage detection and tripping circuit 1 18 connected to a zero-phase current transformer (ZCT) 122 provided so that the fixed conductor on the power supply side of each phase penetrates Detection is performed, the switching mechanism is tripped by the earth leakage trip device 1 19, and the current flowing through the fixed conductor on the load side is detected by the current transformer (CT) 13 1 to detect overcurrent.・ Supplied to the trip circuit 13 2, and when an overcurrent is detected, the overcurrent trip device 13 3 is driven based on the preset overcurrent trip characteristics to trip the opening / closing mechanism. It is a type of earth leakage breaker. Although C T 13 1 is provided for each phase, the illustration of the Z C T of the R phase (the lower phase in FIG. 2) is omitted in FIG. In the present embodiment, the ZCT 122 and the leakage detection / trip circuit 118 are the leakage detection means. The operation of the earth leakage trip device 1 19 is indicated by the earth leakage indicator 1 19 a. The earth leakage indicator 1 19 a is normally used with a button protruding from the cover 1 67 surface in conjunction with the operation of the earth leakage trip device 1 19, but the operation of the earth leakage trip device 1 19 However, the present invention is not limited to this as long as it can display.

The earth leakage breaker of the present embodiment is a three-pole earth leakage circuit breaker, and each pole is connected to the power supply side fixed contact block 101 as a power supply side fixed conductor electrically connected to the power supply side terminal 16 2. Load-side fixed conductor electrically connected to load-side terminals 1 6 4 The load-side fixed contact block 108 is provided at a substantially point-symmetrical position with respect to the center of rotation of the movable contact block 104 as a movable conductor rotatably held. The movable contact stand 104 has a power-side movable contact 152 and a load-side movable contact 154 at point-symmetric positions with respect to the center of rotation. Power supply fixed contact block 1 0 1 has power supply fixed contact 1 5 6 at the position facing power supply movable contact 1 5 2, and load side fixed contact block 1 0 8 faces load side movable contact 1 5 4 The load side fixed contact 1558 is provided at the position where These movable contacts 15 2 on the power supply side, movable contacts 15 4 on the load side, fixed contacts 15 6 on the power supply side, and fixed contacts 15 8 on the load side function as switching contacts. In the present embodiment, the main circuit from the power supply terminal to the load terminal via the on-off contact is formed by the power supply fixed contact block 101, the load fixed contact block 108, and the movable contact block 104. ing. The movable contact block 104, which is mechanically connected to the open / close mechanism 1 1 1 as an open / close mechanism that opens and closes the open / close contact, becomes a fixed contact block on the power supply side when the open / close mechanism 1 1 1 is turned on. Rotate to the position where 101 and load-side fixed contact block 108 are electrically connected. The movable contact stand 104 is rotatably held by a contact shaft 109 serving as a holding member made of an insulating material via a contact spring 110.

This main circuit is housed in a main circuit case 172 formed of an insulator. When the main circuit is housed in the main circuit case 1 7 2, the portion where the power supply side terminal 16 2 of the power supply side fixed contact block 101 is provided and the load side fixed contact block 1 08 4 1 6 4 The portion provided with is protruded from the main circuit case 17 2, but the other portion is located in the main circuit case 17 2 and is electrically insulated from the outside. The contact shaft 109 that holds the movable contact block 104 in a rotatable manner in the main circuit case 17 2 is also made of insulating material, so that the charge is exposed when voltage is applied to the main circuit. There are two parts: the power supply terminal 16 2 and the load terminal 16 4. In this embodiment, the main circuit case 17 2 and the contact shaft 109 are formed of a thermosetting resin having strength such as polynistel resin. In the main circuit case 17 2, high-temperature and high-pressure arc gas is generated between the fixed contact point and the movable contact point on the power supply side and the load side at the time of interruption. Therefore, the main circuit case 172 and the contact shaft 109 are required to withstand the high-temperature and high-pressure arc gas, and polyester resin is used in consideration of the cost of the product. Other resins or ceramics may be used as long as they are insulating materials that can withstand high-temperature and high-pressure arc gas.

 These main circuit cases 17 2 for each phase, switching mechanism 1 11 1, overcurrent trip device 13 3, CT 13 1, overcurrent detection and trip circuit 13 2 The control handle 1 4 1, which is housed in the housing 1 6 5 having the body 1 6 6 and the body cover 1 6 7 and attached to the switchgear mechanism 1 1 1, the power supply side terminal and the load side terminal Are exposed outside the housing 1 65.

The ZCT 1 2 2 that detects leakage is attached to the part of the fixed conductor 1 0 1 exposed from the main circuit case 1 7 2, and the main circuit case 1 7 2 of the fixed conductor 10 8 on the load side is mounted. The exposed portion is equipped with a CΤ131, which detects overcurrent, and the main circuit case 172 is made of a material that can withstand high-temperature and high-pressure arc gas. Τ 1 2 2 and C Τ 1 3 1 are shielded from the arc generated at the switching contact by the main circuit case 17 2. That is, the main circuit case 17 2 has a function as a shielding means for shielding the arc generated at the switching contact, and ZCΤ122 and CΤ131 are arranged outside the shielding means. Is done. As a result, the ZCT 122 can be protected from arc gas generated at the time of interruption, etc., and the reliability of the product can be improved. Also, ∑ ∑ 1 1 ぉ ぉ 2 2 ぉ ぉ 2 ぉ ぉ ぉ 2 ぉ ぉ ぉ ぉ 2 2 2 ぉ 2 丁 丁 丁 2 2 2 2 2 2 丁 2 ぉ ぉ. In this embodiment, heavy parts such as the two are divided into the power supply side and the load side of the main circuit case 1Ί2. The weight balance of the product is improved because it is provided and it is easy to hold it by hand, so that the workability is improved when mounting it on the panel.

 An arc shoe that attracts and cools the arc generated at the time of interruption in the vicinity of the contacts of the fixed contact block 101 on the power supply side, fixed contact block 1〇8 on the load side, and movable contact block 104 in the main circuit case 172. G (arc extinguishing device) 1 7 6 is provided. Further, in this embodiment, an arc discharge port 172a for discharging the cooled arc gas is provided in the main circuit case 172. In this embodiment, the arc discharge port 172a provided on the power supply side of the main circuit case 172 is formed in a cylindrical shape, and the main body cover of the housing 165 is located at a position avoiding the ZCT 122. It communicates with the arc discharge hole 167a opened in 1667. As a result, the arc gas is discharged out of the housing without touching the ZCT, and the insulation deterioration around the ZCT due to the molten metal in the arc gas can be effectively prevented.

In the present embodiment, the portion of the power supply side fixed conductor 101 to which the ZCT 122 is mounted is, as shown in FIGS. 4 and 5, the power supply side fixed conductor 10 of each phase in order to improve the detection accuracy. 1R, 101S, and 101T are arranged close to each other, and an insulating member 191 is arranged between the conductors for ascertaining the insulation distance. In the present embodiment, in order to bring the conductors close to each other, the R-phase fixed conductor 101 R and the Τ-phase fixed conductor 101 are bent into a U-shape, and as shown in FIG. The S-phase fixed conductor 101S is fitted with the insulating material 191 and passed through the ZC 1122, and finally the other parts are placed inside the ZCC122. It is located between the fixed conductors 101R and 101T (the position shown by the two-dot chain line in Fig. 5). When the height of the ZCT 122 is high, as shown in Fig. 5, the S-phase arc discharge port 17 2 a is divided into two parts to avoid the ZCT 122, and the main body cover 16 Connect the arc discharge hole 1 6 7a opened in 7 to discharge the arc gas out of the housing without touching the ZCT. In particular, since three-phase conductors are inserted close to ZCT 122, insulation deterioration of this part is prevented. Is important for improving product reliability.

 The main circuit cases 17 2 are arranged in parallel for three poles, and the holding members 109 are connected so that the movable contact blocks 104 of each pole can be opened and closed substantially simultaneously. In this embodiment, the opening / closing mechanism section 111 is mounted on the upper outside of the main circuit case 172 at the center pole, and is coaxial with the rotation axis of the holding member 109 via the link 111a. Is connected to the rotating arm 109 a of the insulator connected to. As a result, the switching mechanism 1 1 1 is provided outside the main circuit case 17 2 and is connected to the movable contact block 14 via an insulator, so that even if a voltage is applied to the main circuit, No voltage is applied to the switching mechanism 1 1 1.

 An alarm switch, an auxiliary switch, and a voltage trip device that trips in response to an external signal, are installed inside the earth leakage breaker and output the status of the earth leakage circuit breaker, and an undervoltage trip device In this embodiment, when the internal attachment device such as is mounted, it is mounted adjacent to the opening / closing mechanism section 111 at the poles on both sides of the central pole. The opening / closing mechanism 1 1 1 is manually turned ON / OFF by the operation handle 1 4 1 and the overcurrent trip device is used when the current in the main circuit exceeds a predetermined value. The main circuit is shut off by means of 1 3 3.

In the present embodiment, since the switching contact at two locations is opened and closed by the rotation of the movable contact base, the opening and closing mechanism 1 1 1 and the operation handle 1 4 1 to rotate the holding member 109 are provided. It is installed near the holding member 109. For this reason, the arc extinguishing devices installed around the two switching contacts are installed almost symmetrically on the power supply side and the load side with the switching mechanism 111 and the operation handle 141 as the center. Therefore, when the movable contact block 104 is disposed between the ZCT 122 and the CT 131, the opening and closing mechanism 1 1 1 Since the operation handle 1 4 1 is located, it becomes easier to install the operation handle in the center of the earth leakage breaker body. Also, when integrating the dimensions of the earth leakage breaker and the wiring breaker (circuit breaker), The circuit breaker can be obtained by removing the ZCT from the power supply side of the earth leakage breaker of the embodiment and the earth leakage detection means and the earth leakage trip device, so that the earth leakage breaker and the circuit breaker have the same external dimensions. It is easier to manufacture.

 In the present embodiment, the switching mechanism 111 and the overcurrent trip device 133 are insulated from the main circuit and become a non-charged part. Therefore, even if the circuit breaker cover 167 is unavoidably opened in the live state due to addition or replacement of internal accessories, the charged part is not exposed, and a circuit breaker with excellent safety can be obtained. . In this embodiment, a portion from the main circuit case 17 2 of the load-side fixed contact block 10 8 of the main circuit to the load-side terminal 16 4 is provided with a CT 13 1 for detecting a current flowing through the main circuit. The output of the CT 13 1 is supplied to an overcurrent detection / trip circuit 13 2 provided above the CT 13 1. Overcurrent detection The trip circuit 13 2 generates an output based on a predetermined time limit characteristic in the range of about 1.1 times to about 20 times the rated current. The output of the overcurrent detection circuit is supplied to the overcurrent trip device 133. As the overcurrent tripping device 133, a magnetic tripping device that releases the movable core attracted by the permanent magnet by reverse excitation is used. As such a magnetic trip device, for example, the one described in Japanese Patent Application No. 8-62449 can be used. When the movable core of the overcurrent trip device 1 3 3 is released, the latch 1 1 5 contacts the latch 1 1 5 which locks the hook 1 1 1 b of the opening / closing mechanism 1 1 1 1 1 5 Is rotated (clockwise in Fig. 1), and the main circuit is opened by the tripping operation of the opening / closing mechanism 1 1 1. As a result, the circuit is shut off and the overcurrent can be prevented from flowing to the load side.

In the present embodiment, the movable contacts and fixed contacts of the main circuit are housed in the main circuit case 172 made of an insulating material that can withstand high-temperature and high-pressure arc gas. Inexpensive thermoplastic resin may be used as long as it has a minimum strength. Nylon or the like can be used as such a thermoplastic resin. In this embodiment, the front side of the housing 1 65 (operation hand The side of the operating handle 14 1 on the side where the knurls 14 1 are provided): A cover 16 7 b is provided that can be opened and closed by opening and closing the cover 1 6 7 b. It is configured so that maintenance such as installation and replacement of internal accessories can be performed. In the present embodiment, even when the cover 167b is forced to be in a live state, the charged portion is not exposed and the operation of the internal accessory device can be safely performed.

 A modification of this embodiment will be described with reference to FIGS. In this modification, the height is reduced by making the ZC 2 122 into an oval shape, and the fixed conductors 110 1 R, 101 S, and 101 T on the power supply side of each phase are formed into flat plates. They have the same shape. With such a shape, the leakage detection characteristic slightly changes from that of the circular Z C 、, but this characteristic change is corrected by the leakage detection and trip circuit 118 to detect the leakage. In this modification, since the height of ZCΤ is low, as shown in Fig. 8, the S-phase arc outlets 17 2a have the same shape and dimensions as the R-phase and T-phase arc outlets 17 2a. Can be S-phase fixed conductor 1 0 1 S and R-phase fixed conductor 1 0 1 Insulation member 1 9 2 between R and S-phase fixed conductor 1 0 1 S and T-phase fixed conductor 1 0 1 T It may be provided. Other parts are the same as those of the first embodiment shown in FIGS.

 A second embodiment of the present invention will be described with reference to FIGS. 9 to 10. The present embodiment has an overcurrent detection unit that mechanically detects an overcurrent by utilizing deformation of the bimetal due to heat.

 In the present embodiment, leakage detection is performed using the ZCT 122 provided so that the power supply-side fixed conductor 101 of each phase penetrates, and the current flowing through the load-side fixed conductor 108 is detected. This is a thermal-type earth leakage breaker that converts heat into heat by a heater 2 3 1 connected to it and deforms the bi-metal 2 3 2 by this heat to trip the switching mechanism 1 1 1.

In this embodiment, the operation is performed by the heat generated by the heater 2 3 1 and the heater 2 3 1 The bimetal 2 32 forms overcurrent detection means. The heater 231, when the conductor from the load-side fixed contact block 108 to the load-side terminal 16 is bent into a U-shape, reduces its cross-sectional area and increases the electrical resistance. One end of a bimetal 2 32 is fixed to an end of the heater 2 31 on the load side fixed contact block 108 side. The other end of the bimetal 2 32 is a free end, and is bent by the heat generated by the heater 2 3 1 to generate a mechanical output according to the current. In the present embodiment, the bimetal 2 32 is bent in the counterclockwise direction by the heat generated by the heater 2 3 1, and the pressing portion 2 32 a attached to the free end tip presses the transmission mechanism 2 3 3. And rotate counterclockwise. The transmission mechanism 2 33 is rotatably provided, and the latch 1 which is rotated by the pressing of the pressing section 2 32 to lock the hook 1 1 1 b of the opening and closing mechanism 1 1 1. The latch circuit 115 is rotated (clockwise in Fig. 9) by contacting the latch 15 and the main circuit is opened by the tripping operation of the opening / closing mechanism 111.

The earth leakage breaker of the present embodiment is a three-pole earth leakage circuit breaker, and each pole is connected to the power supply side fixed contact block 101 as a power supply side fixed conductor electrically connected to the power supply side terminal 16 2. The load-side fixed contact block 108 serving as a load-side fixed conductor electrically connected to the load-side terminal 16 4 via a heater 23 2 is a movable conductor rotatably held. All of the movable contact tables 104 are provided at substantially point symmetric positions with respect to the rotation center. In this embodiment, as in the first embodiment, the movable contact block 104, the power supply fixed contact block 101, and the load fixed contact block 108 are both movable on the power supply side that function as switching contacts. It has contacts 15 2, load-side movable contacts 15 4, power-supply-side fixed contacts 15 6, and load-side fixed contacts 15 8. In the present embodiment, the fixed contact block 101 on the power supply side, the fixed contact block 108 on the load side, and the movable contact block 104 are loaded from the terminal 162 on the power supply side via a switching contact and overcurrent detection means. The main circuit reaching the side terminals 164 is formed. In this embodiment, ZCT 122 is connected between the main circuit power supply terminal and the switching contact. An overcurrent detection means is provided between the switching contact of the main circuit and the load-side terminal, and the overcurrent detection means using bimetal 232 and the output of the switching mechanism are provided. The structure other than the mechanism for transmitting the signal to the first embodiment is the same as that of the first embodiment.

 This main circuit is housed in a main circuit case 172 formed of an insulator. The live parts exposed when a voltage is applied to the main circuit are at two places: the power supply side terminal 16 2 and the load side fixed contact block 108 to the load side terminal 16 4. The main circuit case 1 7 of the fixed conductor 1 0 8 for the power supply side of each phase is mounted on the exposed part of the main circuit case 1 7 2 to detect the earth leakage. A heater 231 and a bimetal 2 32 as an overcurrent detection means are mounted on the portion exposed from 2. The main circuit case 17 2 is formed so as to surround the switching contact and has a function as a shielding means for shielding the arc generated at the switching contact, and the ZCT 122 and the overcurrent detection means function as this shielding means. It is arranged outside the means. Thus, also in the present embodiment, the ZCT 122 and the overcurrent detecting means can be protected from the arc gas.

A third embodiment of the present invention will be described with reference to FIG. This embodiment has a main circuit from the power supply side terminal to the load side terminal via the switching contact, a switching mechanism that opens and closes the switching contact, and a ZCT322 that detects leakage from the current flowing through the main circuit. Leakage detection means, an earth leakage trip device that trips the switching mechanism based on the output of the earth leakage detection means, and an overcurrent that has a CT 331 and detects overcurrent from the current flowing through the main circuit. A detection means and an overcurrent trip device for tripping the switching mechanism based on the output of the overcurrent detection means are provided, and a ZCT322 is provided between the power supply terminal of the main circuit and the switching contact. An earth leakage breaker with a CT33 between the switching contact of the main circuit and the load-side terminal _; specifically, the main circuit is a power-supply terminal block with a power-supply terminal. 1, Electric Source-side fixed contact 302, power supply-side movable contact 303, movable contact block 304, load-side movable contact 300, load-side fixed contact 303, load-side terminal block with load-side terminal 300 The movable contact block 304 is held by a contact shaft 310 via a contact spring 310. The power-side fixed contact 302, the power-side movable contact 303, the load-side movable contact 300, and the load-side fixed contact 303 are open / closed contacts that shut off the main circuit when an overcurrent or leakage occurs. 3 4 Ν OFF OFF OFF 4 3 4 4 3 4 4 4 4 4 4 4 4 4 4 4 OFF The contact shaft 309 is connected to a mechanism 311 as an opening / closing mechanism, and has a structure in which the switching contact of the main circuit is opened / closed by rotating. ZCΤ32 2 is provided so that the power supply side terminal block 301 of each phase passes through. The CT 331 is provided in at least two of the three phases, and the load-side terminal block 308 passes through the inside. The overcurrent detection and trip circuit 3 17 and the overcurrent trip device 3 3 3 are connected to the current transformer 3 3 1 and trip when an overcurrent flows in the main circuit. In this embodiment, the overcurrent detecting means is composed of C C331 and an overcurrent detecting / tripping circuit 317. ZC Τ 3 2 2 is connected to earth leakage detection and trip circuit 3 18, and earth leakage detection and trip circuit 3 18 is connected to earth leakage trip device 3 19. In the present embodiment, the leakage detecting means is composed of ZCΤ322 and a leakage detecting / tripping circuit 318. The mechanism 311 can open and close the main circuit contacts from the outside by means of the handle 341, and the overcurrent trip device 3333 can be used when an overcurrent flows in the main circuit. Then, remove the latch part 3 15 that locks the mechanism part 3 1 1 and remove the main circuit. Similarly, the earth leakage trip device 319 removes the latch 315 of the mechanical section 311 and trips the main circuit when the earth leakage exceeds the set value in the main circuit. The main circuit element and the main circuit switching element are housed integrally in a housing 365 composed of a molded case 36 6 and a cover 36 7 to constitute an earth leakage breaker. In the above embodiment, a ZCT is provided between the power supply terminal of the main circuit and the switching contact, and a CT is provided between the switching contact of the main circuit and the load terminal. The handle that opens and closes the circuit can be placed in the center of the earth leakage breaker. Therefore, in each of the above embodiments, the design of the switchboard is easy, and the usability is improved, for example, it is easy to manufacture a product in which the external dimensions are integrated with the wiring breaker of the same class. In particular, when several wiring circuit breakers and earth leakage breakers are installed side by side, even if the handle operation parts are arranged in a straight line on the switchboard, the terminal positions on the power supply side and the load side are easy to line up. And connection of the conductor to the terminal is facilitated.

 In addition, if the handle is located at the center of the circuit breaker and earth leakage breaker, the same panel structure can be used to reversely install the circuit breaker, earth leakage breaker on the power side and load side.

Industrial applicability

 ADVANTAGE OF THE INVENTION According to this invention, it is small and can achieve the same size as a circuit breaker, and it is possible to obtain an earth leakage breaker with excellent reliability.

Claims

The scope of the claims 1. Power supply Main circuit from the regular terminal to the load side terminal via the switching contact, a switching mechanism that opens and closes the switching contact, and a current leakage through the main circuit with a zero-phase current transformer. Leakage detecting means for detecting the current, an earth leakage trip device for tripping the switching mechanism based on an output of the earth leakage detecting means, and a current transformer for detecting an overcurrent from a current flowing through the main circuit. An overcurrent detecting means, and an overcurrent tripping device for tripping the switching mechanism by an output of the overcurrent detecting means, wherein the overcurrent tripping device is provided between the power supply terminal of the main circuit and the switching contact. An earth leakage breaker comprising: a zero-phase current transformer; and the current transformer arranged between the switching contact of the main circuit and the load-side terminal. 2. A main circuit from the power supply terminal to the load terminal via the switching contact, a switching mechanism that opens and closes the switching contact, and a zero-phase current transformer, which leaks current from the current flowing through the main circuit. An earth leakage detecting means for detecting, an earth leakage trip device for tripping the opening and closing mechanism based on an output of the earth leakage detecting means, and an overcurrent having a current transformer and detecting an overcurrent from a current flowing through the main circuit. Current detecting means, and an overcurrent tripping device for tripping the switching mechanism based on the output of the overcurrent detecting means, wherein the zero is provided between the power supply terminal of the main circuit and the switching contact. A phase current transformer is arranged, and the current transformer is arranged between the switching contact of the main circuit and the load terminal, and the switching is performed between the switching contact and the zero-phase current transformer. Shielding means for shielding the arc generated at the contacts is provided. Electric breakers. 3. A main circuit from the power supply side terminal to the load side terminal via the switching contact, a switching mechanism that opens and closes the switching contact, and a zero-phase current transformer that leaks current from the current flowing through the main circuit. A leakage detecting device for detecting, a leakage detecting device for performing a trip of the opening / closing mechanism by an output of the leakage detecting device, and a current transformer. An overcurrent detecting means for detecting an overcurrent from a current flowing through the main circuit; and an overcurrent tripping device for tripping the switching mechanism by an output of the overcurrent detecting means. The zero-phase current transformer is provided between the power supply terminal and the switching contact.The current transformer is provided between the switching contact of the main circuit and the load terminal. An earth leakage breaker, characterized in that shielding means for shielding an arc generated at the switching contact is provided between the current transformer and the current transformer.  4. Main circuit from the power supply side terminal to the load side terminal via the switching contact, a switching mechanism that opens and closes the switching contact, and a zero-phase current transformer that leaks current from the current flowing through the main circuit. An earth leakage detecting means for detecting, an earth leakage trip device for tripping the opening and closing mechanism based on an output of the earth leakage detecting means, and an overcurrent having a current transformer and detecting an overcurrent from a current flowing through the main circuit. Current detecting means, and an overcurrent tripping device for tripping the switching mechanism based on the output of the overcurrent detecting means, wherein the zero is provided between the power supply terminal of the main circuit and the switching contact. A phase current transformer is provided, and the current transformer is provided between the switching contact of the main circuit and the load-side terminal, between the switching contact and the zero-phase current transformer and the switching. Shields the arc generated at the switching contact between the contact and the current transformer Earth leakage breaker, characterized in that it is disposed a shielding means. 5. A main circuit from the power supply terminal to the load terminal via the switching contact, a switching mechanism that opens and closes the switching contact, and a zero-phase current transformer that leaks current from the current flowing through the main circuit. An earth leakage detecting means for detecting, an earth leakage trip device for tripping the opening and closing mechanism based on an output of the earth leakage detecting means, and an overcurrent having a current transformer and detecting an overcurrent from a current flowing through the main circuit. A current detecting means, an overcurrent tripping device for tripping the switching mechanism based on an output of the overcurrent detecting means, and a shielding means for shielding an arc generated at the switching contact; Contact between the current transformer and the current transformer with respect to the shielding means. And an earth leakage breaker arranged on the opposite side.  6. Power supply (Main circuit from the law terminal to the load side terminal via the switching contact, a switching mechanism that opens and closes the switching contact, and a current leakage through the main circuit with a zero-phase current transformer Leakage detecting means for detecting the current, an earth leakage trip device for tripping the switching mechanism based on an output of the earth leakage detecting means, and a current transformer for detecting an overcurrent from a current flowing through the main circuit. An overcurrent detecting means, an overcurrent tripping device for tripping the switching mechanism based on an output of the overcurrent detecting means, and an arc formed around the switching contact and generated at the switching contact. And a shielding means for shielding the electric current, wherein the zero-phase current transformer and the current transformer are arranged outside the shielding means.  7. The fixed conductor on the power supply side electrically connected to the terminal on the power supply side, the fixed conductor on the load side electrically connected to the terminal on the load side, and the fixed conductor on the power supply side electrically connected to the open / close mechanism during the ON operation. A main circuit having a movable conductor for electrically connecting the load-side fixed conductor to the load-side fixed conductor, a main circuit case formed of an insulator to house the main circuit, and a zero-phase current transformer. Electricity flowing through the main circuit Leakage detecting means for detecting a leakage from a force, a leakage tripping device for tripping the switching mechanism by an output of the leakage detection means, and a current flowing through the main circuit having a current transformer. An overcurrent detecting means for detecting an overcurrent from the circuit, and an overcurrent tripping device for tripping the switching mechanism based on an output of the overcurrent detecting means. A zero-phase current transformer was mounted, the current transformer was mounted on the fixed conductor on the load side of the main circuit, and the main circuit case was disposed between the zero-phase current transformer and the current transformer. An earth leakage circuit breaker. 8. The main circuit case is formed in a unit structure that covers a current-carrying part for each phase, and is connected for a plurality of phases so that the movable conductors of each phase open and close substantially simultaneously. The above switchgear is mounted on the main circuit case of one of the multiple phases. The earth leakage breaker according to claim 7, wherein a structure is mounted.  9. A main circuit from the power supply terminal to the load terminal via the switching contact, a switching mechanism that opens and closes the switching contact, and a zero-phase current transformer that leaks current from the current flowing through the main circuit. An earth leakage detecting device for detecting, an earth leakage trip device for tripping the opening / closing mechanism based on an output of the earth leakage detecting device, an overcurrent detecting device for detecting an overcurrent from a current flowing through the main circuit; An overcurrent trip device for tripping the switching mechanism based on the output of the overcurrent detection means, and the zero-phase current transformer is arranged between the power supply terminal of the main circuit and the switching contact. An earth leakage circuit breaker, wherein the overcurrent detection means is provided between the switching contact of the main circuit and the load terminal.  10. Main circuit from the power supply side terminal to the load side terminal via the switching contact, a switching mechanism for opening and closing the above switching contact, and a zero-phase current transformer. An earth leakage detecting device for detecting an overcurrent, an earth leakage trip device for tripping the switching mechanism based on an output of the earth leakage detecting device, an overcurrent detecting device for detecting an overcurrent from a current flowing through the main circuit, An overcurrent trip device for tripping the switching mechanism by the output of the overcurrent detection means, and a shielding means formed to surround the switching contact and shielding an arc generated at the switching contact. An earth leakage breaker, comprising: the zero-phase current transformer and the overcurrent detection means arranged outside the shielding means.