JPH05342976A - Earth leakage breaker - Google Patents

Abstract

PURPOSE:To provide a highly reliable earth leakage breaker capable of preventing the burning of a trip coil resulted from the continuous pushing of a test button by allowing no simulated earth leakage current flow even if a handle is constrained at an off time when the breaker is reversely connected. CONSTITUTION:A test conductor is provided with a test button switch composed of a test spring 11 to be operated by a test button 10, and a plate spring 12 to be touched by the test spring 11. Actuators 13, 23, whose positions are changed by the crossbar 5 of a breaker, are provided also. Even if the plate spring 12 is pushed down by the actuators 13, 23 so that a handle is constrained at the off time of the breaker, the test spring 11 is not allowed to touch the plate spring 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth leakage circuit breaker, and more particularly to preventing a trip coil from burning.

[0002]

2. Description of the Related Art A conventional earth leakage breaker will be described with reference to FIGS. 6 is a front view schematically showing the inside, FIG. 7 is a view partially showing the electromagnetic trip device of FIG. 6, FIG. 8 is a view of FIG. 7 from the left, and FIG. 9 is a view of FIG. 8 from the right. 10 is the same as FIG. 8 showing a trip, and FIG. 11 is a diagram of FIG. 10 viewed from the right. In the figure, 1 is a circuit breaker case, 2 is a power source side terminal part, 3 is a load side terminal part, 4 is a mover, 5 is a crossbar for connecting the mover 4 of each pole, 6 is an opening / closing mechanism part, 7
Is a trip bar of the opening / closing mechanism 6, 8 is an electromagnetic trip device,
Reference numeral 9 is a mount, 10 is a test button, and the test spring 11 and the leaf spring 12 constitute a test button switch.
An actuator 13 is rotatably mounted on the mounting base 9 by a pin 14, and is driven by the trip bar 7 when the circuit breaker trips to push down the leaf spring 12 so that the test spring 11 does not come into contact with the leaf spring 12.

Next, the circuit of the conventional earth leakage breaker shown in FIGS. 6 to 11 and its test circuit will be described with reference to FIG. In FIG. 12, 15 is a main circuit and 16 is a main circuit 1.
5, 17 is a switching contact, 17 is a zero-phase current transformer provided on the load side of the switching contact 16, 18 is an amplifier connected to the output of the zero-phase current transformer 17, and 19 is conductive by the output of the amplifier 18. A controlled thyristor 20, a trip coil of the electromagnetic trip device 8 that is energized and controlled by the thyristor 19 and is energized when the main circuit 15 leaks to open the switching contact 16, and 21 is a load from the switching contact 16. R phase on the side,
A transformer 22 connected between the T phases and supplying the operating voltage to the amplifier 18 and energizing the trip coil 20;
Is wound around the zero-phase current transformer 17, and the main circuit 1 is connected to the load side of the switching contact 16 via the test button 10 like the transformer 21.
5 is a test conductor connected between the R phase and the T phase.

Next, the operation will be described. Zero-phase current transformer 1
When leakage occurs in the main circuit 15 on the load side from 7, and a zero-phase current flows, this zero-phase current is picked up by the zero-phase current transformer 17, amplified by the amplifier 18, and given to the gate of the thyristor 19 as a gate signal. Be done. Thus, the thyristor 19 becomes conductive, a current flows from the secondary winding of the transformer 21 through the trip coil 20 and the thyristor 19, the trip coil 20 is energized, and the switching contact 16 is opened.

Next, the operation of the test circuit will be described.
When the test button 10 is closed, in other words, the test button 10 is pressed against the spring force of the test spring 11 to bring the test spring 11 into contact with the leaf spring 12, and the test button switch section is closed. Test conductor 22 from the T phase through the leaf spring 12 and the test spring 11
A simulated earth leakage current flows as indicated by an arrow in FIG. 1 and is picked up by the zero-phase current transformer 17 to open the switching contact 16 as in the case of a normal earth leakage accident. This allows
It is confirmed that there is no failure in the earth leakage breaker.
On the other hand, if the switching contact 16 is not opened, there is a failure somewhere in the earth leakage breaker.

When the circuit breaker is turned on and off, the trip bar 7
Since the actuator does not move, the actuator 13 is in the state shown in FIGS. 7 to 9 apart from the trip bar 7. Therefore, when the test button 10 is pressed as described above, the test spring 11 comes into contact with the leaf spring 12 and the test button switch section is released. Although closed, the trip bar 7 moves to rotate the actuator 13 as shown in FIGS. 10 and 11 when the circuit breaker trips, so that the leaf spring 12 is pressed by the actuator 13 and does not come into contact with the test spring 11. , Test button 1
The test button switch does not close even if 0 is pressed.

[0007]

In the conventional earth leakage circuit breaker as described above, when the earth leakage circuit breaker is attached to a so-called board such as a switchboard, it may be connected to the power source side of the earth leakage breaker depending on the direction of the conductor of the main circuit 15. It may be necessary to reverse the load side for mounting. In this way, when the circuit breaker is reversely connected (in FIG. 12, the power supply side and the load side are reversed), the circuit breaker is in the off state, and the handlebar lock or lock cover is attached to the handle of the circuit breaker ( That is, when the handle is restrained in the off state) and the test button 10 is continuously pressed, the test spring 11 comes into contact with the leaf spring 12 to close the test button switch portion and the trip coil 20 is urged. However, if the handlebar is off, the trip bar 7 will not move and will not trip. The actuator 13 will not rotate, and the test button switch will remain closed, so a simulated leakage current will flow from the main circuit 15. Then, there was a problem that the trip coil 20 was burned.

The present invention has been made in order to solve such a problem, and prevents the simulated leakage current from flowing even if the handle is restrained off when the circuit breaker is reversely connected and is off. An object of the present invention is to obtain a highly reliable earth leakage circuit breaker capable of preventing the trip coil from being burnt out due to continuous pressing.

[0009]

SUMMARY OF THE INVENTION An earth leakage circuit breaker according to the present invention is provided with a test button switch consisting of a test spring operated by a test button and a leaf spring with which the test spring contacts, and a cross of the circuit breaker. An actuator whose position is changed by a bar is provided, and the flat spring is pushed down by this actuator so that the test spring does not come into contact with the flat spring when the circuit breaker is off or trips.

[0010]

In the present invention, the test button switch is held in the open state when the circuit breaker is turned off and when the circuit breaker is turned off by utilizing the change in the position of the crossbar when the circuit breaker is turned on and off.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. 1 is a partial view of the electromagnetic trip device, FIG.
1 is a view of FIG. 1 from the left, FIG. 3 is a view of FIG. 2 from the right, FIG. 4 is the same view as FIG. 2 showing the off and trip times, and FIG.
Is a diagram viewed from the right, and the same or corresponding portions as those of the conventional one are denoted by the same reference numerals and the description thereof is omitted. In the figure, 23 is abutted on the upper surface of the crossbar 5 and
The operating rod is moved up and down by means of a pin 24 and is connected to the base of the actuator 13.

When the circuit breaker is turned on, the crossbar 5 is shown in FIGS.
Since the operating rod 23 is not raised and the actuator 13 is in the state shown in FIGS. 1 to 3 in the state shown in FIG. 3, when the test button 10 is pushed, the test spring 11 comes into contact with the leaf spring 12 and the test button switch portion. However, when the circuit breaker is turned off or tripped, the crossbar 5 rotates as shown in FIGS. 4 and 5 to raise the operating rod 23 and rotate the actuator 13, so that the leaf spring 12 is moved by the actuator 13. The test button switch portion is not closed even when the test button 10 is pushed because it is pressed and does not come into contact with the test spring 11. That is, even if the handle is restrained when the circuit breaker is off, the test button switch section can be held in the open state, so that the simulated leakage current does not flow even when the circuit breaker is reversely connected and turned off.

[0013]

As described above, according to the present invention, even if the handle is restrained when the circuit breaker is reversely connected and the handle is restrained, the simulated leakage current does not flow, so that the test button is continuously pushed. There is an effect that it is possible to obtain a highly reliable coil that can prevent the removal coil from burning.

[Brief description of drawings]

FIG. 1 is a partial configuration diagram showing an embodiment of the present invention.

FIG. 2 is a diagram of FIG. 1 viewed from the left.

FIG. 3 is a diagram of FIG. 2 viewed from the right.

FIG. 4 is the same diagram as FIG. 2 showing an off state and a trip state.

FIG. 5 is a diagram of FIG. 4 viewed from the right.

FIG. 6 is a front view showing a conventional one.

FIG. 7 is a partial configuration diagram of FIG. 6.

FIG. 8 is a diagram of FIG. 7 viewed from the left.

9 is a diagram of FIG. 8 viewed from the right.

FIG. 10 is the same diagram as FIG. 8 showing a trip.

FIG. 11 is a diagram of FIG. 10 viewed from the right.

FIG. 12 is a diagram showing the circuit of FIG. 6 and its test circuit.

[Explanation of symbols]

 5 Crossbar 6 Open / close mechanism 7 Trip bar 8 Electromagnetic trip device 10 Test button 11 Test spring 12 Leaf spring 13 Actuator 15 Main circuit 16 Open / close contact point 17 Zero-phase current transformer 20 Trigger coil 22 Test conductor 23 Actuating rod

Claims (1)

[Claims] 1. A zero-phase current transformer that detects a leakage current in a main circuit, a trip coil that is energized when an output is generated in the zero-phase current transformer to open an opening / closing contact of the main circuit, and the zero. An earth leakage circuit breaker comprising a test conductor wound around a phase current transformer and connected to a main circuit via a test button, wherein a test spring operated by the test button and a plate in which the test spring is in contact with the test conductor. A test button switch consisting of a spring is provided, and an actuator whose position is changed by the crossbar of the circuit breaker is provided. This actuator pushes down the leaf spring so that the test spring does not come into contact with the leaf spring when the circuit breaker is off or trips. The earth leakage circuit breaker characterized by having done.