JP2013034287A - Distribution board disconnecting cable run after overheat detection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect an overheat state of many screw connection parts provided on a cable run by a single detector, and to secure safety by disconnecting the cable run on the detection.SOLUTION: A master breaker 5 and an overheat detector 7 are separately provided inside a power distribution board case. A detection line 74 is wired to a case 73 of the overheat detector 7, and a sensor circuit 75 and a first switch 76 are provided on the detection line 74. An output line 77 of the sensor circuit 75 is connected to an average value circuit 79 through an integrated input circuit 78. A determination circuit 80 compares an average value with a threshold to determine an overheat state of screw connection parts of various in-board apparatuses including the master breaker 5. Once an overheat state is determined, the output circuit 82 excites an electromagnetic coil 84 to open the first switch 76 and to close a second switch 87 on a pseudo-leak circuit 86, and thereby supplies a pseudo-leak current to the master breaker 5 to open a main contact 57, thereby disconnecting the cable run.

Description

  The present invention relates to a distribution board provided with a mechanism for detecting an overheating state of a screw connection portion and interrupting an electric circuit after detection.

  In general, devices such as circuit breakers and terminal blocks installed in the distribution board use screws for the terminal part, so if the contact between the power seat and the crimp terminal becomes unstable due to the looseness of the screws, the arc Discharge occurs and tends to overheat. Therefore, conventionally, a technique has been proposed in which a sensor circuit for detecting an overheated state of the terminal portion is incorporated in the breaker.

  For example, in Patent Document 1, both ends of a sensor circuit 101 as shown in FIG. 4 are connected to a terminal screw 102 and a power supply seat 103, and based on the potential difference between these terminal components, the power supply seat 103 and the crimp terminal 104 are connected. A breaker for detecting poor contact is described.

JP 2009-245836 A

  By the way, there are a plurality of breaker terminals on the primary and secondary sides, and the distribution board has screws such as terminal blocks, limiters, and copper bars in addition to the main breaker and branch breaker. There are a number of electrical connections used. For this reason, when the sensor circuit 101 as shown in FIG. 4 is provided in a large number of screw connection portions, there is a problem that the number of lead wires for detection increases and the inside of the distribution board becomes complicated.

  Accordingly, an object of the present invention is to provide a distribution board capable of detecting an overheated state of a large number of screw connection portions with a single detector and interrupting an electric circuit during detection.

In order to solve the above problems, the present invention provides the following distribution board.
(1) A detector case in which a main breaker that cuts off the electric circuit and an overheat detector that detects the overheating state of the screw connection on the electric circuit are provided inside the distribution board case, and the overheat detector is independent from the main circuit breaker. A sensor circuit connected to the input line of the distribution board and the branching copper bar inside the detector case, a determination circuit for determining an overheat state of the screw connection portion based on the output of the sensor circuit, and an overheat A distribution board comprising a shut-off circuit that shuts off the main breaker when a state is determined.

(2) A distribution board characterized in that the overheat detector has a plug-in terminal to be attached to and detached from the branching copper bar, and the detector case is arranged on the branching copper bar side by side with the branch breaker.

(3) A distribution board characterized in that the breaker circuit includes a pseudo-leakage circuit that causes a pseudo-leakage current to flow through the main breaker.

(4) When the overheat detector determines that an overheat state is detected, a first switch that cuts off current passing through the sensor circuit, a second switch that closes the pseudo-leakage circuit, a reset button that opens the pseudo-leakage circuit, And an actuator for driving the first switch and the second switch.

  According to the distribution board of the present invention, the main breaker and the overheat detector are separately provided in the distribution board case, and the sensor circuit of the overheat detector is connected to the input line of the distribution board and the branching copper bar. A single detector can detect not only the main breaker but also many screw connections such as terminal blocks, limiters, copper bars, etc. connected to it, and the main breaker can be operated at the time of detection. There is an effect that can be blocked.

It is a front view of the distribution board which shows one Embodiment of this invention. It is a circuit diagram which shows the structure of a master breaker and an overheat detector. It is a circuit diagram which shows operation | movement of a master breaker and an overheat detector. It is a circuit diagram which shows the conventional sensor circuit for circuit breakers.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. A distribution board 1 shown in FIG. 1 includes a terminal block 3, a limiter 4, a main breaker 5, an overheat detector 7, and a branch breaker 8 inside a distribution board case 2. However, the present invention is not limited to the distribution board 1 shown in FIG. 1 and can be implemented by adding different types of breakers or omitting one or both of the terminal block 3 and the limiter 4.

  In the distribution board 1 shown in FIG. 1, three input lines 11 drawn from the outside are connected to the first input terminal 31 of the terminal block 3. The 1st input terminal 31 is connected to the 1st output terminal 32 on the same terminal metal fitting, and the 1st output terminal 32 is connected to the primary side terminal 41 of the limiter 4 by the lead wire 21 which comprises a part of electric circuit. The first input terminal 31 and the first output terminal 32 of the terminal block 3 are screw connection portions provided with terminal screws 35 and 36, respectively.

  The primary side terminal 41 of the limiter 4 is connected to the secondary side terminal 42 via an internal wiring (not shown). These terminals 41 and 42 are also screw connection portions provided with terminal screws 43 and 44. The secondary side terminal 42 of the limiter 4 is connected to the second input terminal 33 of the terminal block 3 by the lead wire 22 constituting a part of the electric circuit, and the second input terminal 33 is connected to the second output terminal 34 on the same terminal fitting. It is connected. The second input terminal 33 is a screw connection portion provided with a terminal screw 37.

  The second output terminal 34 of the terminal block 3 is connected to the primary side terminal 51 of the main breaker 5, and the primary side terminal 51 is connected to the secondary side terminal 52 via an electric wire 56 (see FIG. 2) constituting a part of the electric circuit. It is connected. The primary and secondary terminals 51 and 52 are screw connection portions provided with terminal screws 53 and 54, respectively. The secondary terminal 52 of the main breaker 5 is connected to the secondary terminal 72 of the overheat detector 7 via the relay copper bar 13 and the branching copper bar 14.

  The relay copper bar 13 is connected to the branching copper bar 14 with screws 15, and the branching copper bar 14 extends in the longitudinal direction of the distribution board case 3. The overheat detector 7 includes a casing 73 having the same side shape as that of the branch breaker 8, more specifically, a casing 73 having the same depth and height as the branch breaker 8 and a width dimension larger than (for example, twice) the branch breaker 8. The branching copper bar 14 is mounted at a designated position so as to be aligned with the branching breaker 8.

  The secondary terminal 72 of the overheat detector 7 is a plug-in terminal that does not require screw tightening, and is detachably connected to the branching copper bar 14. The primary terminal 71 of the overheat detector 7 is a terminal connected to the input line 11 of the distribution board 1, and is connected to the first input terminal 31 of the terminal block 3 by the lead wire 23.

  2 and 3 show the internal circuit of the main breaker 5 and the overheat detector 7 with the terminal block 3 omitted. Three electric wires 56 (voltage lines L1, L2 and neutral wire N) are wired to the breaker case 55 of the main breaker 5, and the main contact 57 for opening and closing the electric circuit on the electric wire 56 and the overcurrent flowing through the electric circuit are sensitive. Bimetal 58 (only voltage lines L1 and L2) is disposed.

  Three detection lines 74 are wired to the detector case 73 of the overheat detector 7, and the potential difference between the primary side terminal (input line connection terminal) 71 and the secondary side terminal (branching copper bar connection terminal) 72 is respectively provided. Is provided, and a first switch 76 for opening and closing the sensor circuit 75 is provided. The sensor circuit 75 is not limited to a specific configuration. For example, an input / output insulation type circuit using a photocoupler 105 (see FIG. 4) can be used.

  An output line 77 of the sensor circuit 75 is connected to an average value circuit 79 via an integrated input circuit 78. The average value circuit 79 obtains an average value from the output of the sensor circuit 75, the determination circuit 80 compares the average value with a threshold value, and a number of screw connection portions (terminals 31, 32, 33 shown in FIG. 1) provided on the electric circuit. , 34, 41, 42, 51, 52, the copper bar connecting portion 15) is judged to be overheated.

  When the determination circuit 80 determines an overheated state, the determination result is held in the self-holding circuit 81 for a predetermined time, and during this time, the output circuit 82 outputs a drive signal to excite the electromagnetic coil 84 that is an actuator. The electromagnetic coil 84 opens the first switch 76 on the detection line 74 via the link 85 and simultaneously closes the second switch 87 on the pseudo leakage circuit 86.

  The pseudo-leakage circuit 86 is connected to the two electric wires 56 (L1, N) of the main breaker 5, and when the second switch 87 is closed, a pseudo-leakage current of a value determined by the resistor 88 is caused to flow through the main breaker 5. The trip coil (not shown) is operated to open the main contact 57 to cut off the electric circuit. The overheat detector 7 is provided with a handle 89 (see FIG. 1) for closing the first switch 76 and a reset button 90 for opening the second switch 87 at the time of recovery.

  In the distribution board 1 configured as described above, when the electric circuit is in a normal state, as shown in FIG. 2, the electromagnetic coil 84 of the overheat detector 7 is demagnetized, the first switch 76 is closed, and the second switch 87 is opened. The pseudo earth leakage circuit 86 is in an open circuit state, and the main contact 57 of the main breaker 5 is closed. On the other hand, when a contact failure occurs in the screw connection part somewhere on the electric circuit including the terminal block 3, the limiter 4, the main breaker 5, and the copper bars 13 and 14, the determination circuit 80 determines the overheat state, and the output circuit 82 Excites the electromagnetic coil 84.

  Thereby, as shown in FIG. 3, the 1st switch 76 opens, the 2nd switch 87 closes, and the pseudo electric leakage circuit 86 will be in a closed circuit state. Then, the pseudo leakage current flows to the main breaker 5, the main contact 57 is opened, and the electric circuit is interrupted. At the time of recovery, the reset button 90 is pressed, the second switch 87 is opened, the pseudo leakage circuit 86 is opened (see FIG. 2), and after loosening of the screws is eliminated, the handle 59 (see FIG. 1) of the main breaker 5 Is turned on, the main contact 57 is closed, the handle 89 of the overheat detector 7 is turned on, and the first switch 76 is closed.

  According to this distribution board 1, the main breaker 5 and the overheat detector 7 are separately provided inside the distribution board case 2, and the sensor circuit 75 of the overheat detector 7 is connected to the input line 11 and the branching copper of the distribution board 1. Since it is connected to the bar 14, not only the main breaker 5, but also a number of screw connection parts 31, 32, 33, 34, 41, 42, including the terminal block 3, limiter 4, and copper bars 13, 14 connected thereto. The overheated state 51 and 52 can be easily detected by the single detector 7. There is also an advantage that the overheat detector 7 can be arranged on the branching copper bar 14 side by side with the branch breaker 8.

  The present invention is not limited to the above-described embodiment, and a lamp for adding a circuit breaker for a primary feeding circuit, a circuit breaker for an electric light contract by time zone, or the like as an in-panel device or notifying an overheated state of a screw connection portion In the range which does not deviate from the gist of the invention, such as providing the sensor in the detector case of the overheat detector 7, it is also possible to change the configuration of each part and the wiring order as appropriate.

1 distribution board 2 distribution board case 3 terminal block 4 limiter 5 master breaker 7 overheat detector 8 branch breaker 11 input line 13 copper bar for relay 14 copper bar for branch 73 detector case 75 sensor circuit 76 first switch 80 judgment Circuit 84 Electromagnetic coil 86 Pseudo leakage circuit 87 Second switch 90 Reset switch

Claims (4)

  Inside the distribution board case, a main breaker that cuts off the electric circuit and an overheat detector that detects the overheat state of the screw connection on the electric circuit are provided, and the overheat detector has a detector case that is independent from the main circuit breaker, Inside the detector case, a sensor circuit connected to the input line of the distribution board and the copper bar for branching, a determination circuit for determining the overheat state of the screw connection part based on the output of the sensor circuit, and the overheat state are determined A distribution board comprising a shut-off circuit that shuts off the main breaker when it is turned on.   The distribution board according to claim 1, wherein the overheat detector includes a plug-in terminal that is attached to and detached from the branching copper bar, and the detector case is arranged on the branching copper bar side by side with the branch breaker.   The distribution board according to claim 1 or 2, wherein the interrupting circuit includes a pseudo-leakage circuit that causes a pseudo-leakage current to flow through the main breaker. The overheat detector includes a first switch that cuts off current passing through the sensor circuit, a second switch that closes the pseudo-leakage circuit, a reset button that opens the pseudo-leakage circuit, and first and first switches when an overheat state is determined. The distribution board according to claim 3, further comprising an actuator for driving two switches.

Images