JPH05205606A - External annunciator of circuit breaker - Google Patents

Abstract

PURPOSE:To reduce the number of signal conductors so as to simplify the work of inter-wiring plural signal switches for the external annunciator of a circuit breaker by interconnecting the signal switches with predetermined relationship, and then leading out the normally-on contact of one of the switches, and also the normally-off contact and common contact of the other respectively as their relevant terminals. CONSTITUTION:A switch 4 is connected at its normally-on contact 42 to the common contact 31 of a switch 3. The switch 3 is connected also at its normally-on contact 32 to a normally-on signal terminal 51 and at its normally-off contact 33 to a normally-off signal terminal 52, and the switch 4 is connected at its normally-off contact 43 to a normally-on signal terminal 53, and the switch 3 is further connected at the common contact 31 to a common signal terminal 54 so that all these contacts may be led outside via their respective relevant terminals. An annunciator 61 which announces that a device is in its normal condition is connected to the terminal 51, and another annunciator 62 which announces that the device is in its compulsory contact-parted condition is connected to the terminal 52. A third annunciator 63 which announces that the device is in its short-circuited condition is connected to also the terminal 53, and it has power impressed thereupon via the terminal 54. Only the annunciator 61 is then activated when the device is in its normal condition, and it is deactivated when the device goes wrong so that the annunciators 62, 63 may be activated. The number of the terminals being led outside can thus be reduced so as to simplify the inter-wiring of the switches for the external annunciator of a circuit breaker.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an external alarm device for a circuit breaker which interrupts an electric circuit in response to an overcurrent such as a short circuit current or an overload current.

[0002]

2. Description of the Related Art Generally, a circuit connecting a power source and a load is equipped with a circuit breaker that opens and closes the circuit in response to a handle operation and forcibly opens the circuit when an overcurrent occurs. The load equipment is protected. If necessary, the circuit breaker may respond to the operating state of the circuit breaker, such as an auxiliary switch that sends a signal linked to the opening and closing of the electric circuit, or an alarm switch that responds to the forced opening in the event of an overcurrent. There is a case where a signal switch for controlling the electric power supply is stored, and in response to the signal of the signal switch, the electric power supply state is managed externally by a display or an alarm.

Further, recently, in order to widely manage the electric power supply state, for example, a pre-alarm switch for notifying the supply current of the electric circuit before the forced opening operation of the circuit breaker and the leakage current of the electric circuit are predetermined. A signal switch that responds to the electric power supply state of the electric circuit, such as a leak alarm switch that notifies when the value exceeds a certain value, has also been housed.

[0004]

In the above external notification device for a circuit breaker, however, the number of signal switches housed in the circuit breaker begins to gradually increase, and accordingly, the signal switches are led to the outside. The number of signal lines has also increased. In particular,
The signal switch switches the common contact between the normally closed contact and the normally open contact so that the display can be performed even in the normal state, so-called C.
Contact switches have been used, which has been a factor in increasing the number of signal lines.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an external notification device for a circuit breaker in which the number of signal lines leading to the outside can be reduced and the wiring work can be simplified. To do.

[0006]

In order to solve the above-mentioned problems, an external notification device for a circuit breaker according to claim 1 has a common contact of one signal switch of at least two types of signal switches and another signal switch. Connect to the normally closed contact of
The normally closed contact of one signal switch, the normally open contact of one signal switch, the normally open contact of the other signal switch, and the common contact of the other signal switch are connected to the normally closed signal terminal and one of the normally open contacts. A signal terminal, the other normally open signal terminal, and a common signal terminal are respectively led to the outside.

[0007]

In the normal state, the external alarm device of the circuit breaker has the normally closed signal terminal closed to the common signal terminal, the normally open signal terminals opened, and at least one of the other signal switches. When one of them operates, the normally closed signal terminal opens with respect to the common signal terminal and the normally open signal terminal on the operating side closes, and each normally open signal terminal, normally closed signal terminal and common signal terminal Therefore, it becomes possible to signal the operation states of at least two types of signal switches to the outside.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an external notification device for a circuit breaker according to the present invention will be described below with reference to FIG.

The electric circuit 1 connecting the power source and the load is equipped with a circuit breaker 2 which opens and closes the electric circuit 1 in response to an operation of the handle 21 and forcibly opens the electric circuit 1 when an overcurrent occurs.

The circuit breaker 2 includes an electric circuit contact 22 which is connected in series to the electric path 1 and a current such as a bimetal plate or an electromagnet device which is connected in series to the electric path 1 and detects an overcurrent such as an overload current or a short circuit current. The detection device 23 and the electric path contact 22 are opened and closed in response to the operation of the handle 21, and the current detection device 23
Switching mechanism that forcibly opens the electrical circuit contacts 22 in response to
24, and the first signal switch 3 which is a cut-off alarm switch for switching the common contact 31 from the normally closed contact 32 to the normally open contact 33 in response to the forced opening of the electric circuit contact 22 of the opening / closing mechanism section 24. ing.

Further, the circuit breaker 2 includes a zero-phase current transformer 25 having the electric path 1 as a primary winding, a leakage detection circuit 26 for determining the level of the output of the zero-phase current transformer 25, and the leakage current. In response to the detection circuit 26, the common contact 41 is changed from the normally closed contact 42 to the normally open contact 43.
And a second signal switch 4 which is an earth leakage alarm switch for switching to.

Therefore, in the first signal switch 3 and the second signal switch 4, the common contact 31 of the first signal switch 3 is connected to the normally closed contact 42 of the second signal switch 4,
Furthermore, the normally closed contact 32 of the first signal switch 3 is connected to the normally closed signal terminal 51, the normally open contact 33 of the first signal switch 3 is connected to the first normally open signal terminal 52, and the second signal switch 4 is connected. Normally open contact 43
Is connected to the second normally open signal terminal 53, and the common contact 31 of the first signal switch 3 is connected to the common signal terminal 54 to lead to the outside.

A first informing device 61 such as an indicator or a transmission relay for announcing the normal state is connected to the normally closed signal terminal 51, and the first normally open signal terminal 52 is forcibly connected to the first normally open signal terminal 52. An indicator for notifying that the contact is in the open state, a second notifying device 62 such as an alarm or a transmission relay is connected, and an indicator for notifying that the second normally open signal terminal 53 is in the leakage state,
A third alarm device 63 such as an alarm device or a transmission relay is connected and is applied from the power source through the common signal terminal 54.

However, in a normal state, the first and second
The signal switches 3 and 4 of FIG.
Since it is connected to Nos. 2 and 42, the first notification device 61 operates, and the second and third notification devices 62 and 63 do not operate. From this state, if the circuit contacts 22 are forcibly opened due to overcurrent or if a leakage current occurs, the first
Alternatively, the common contacts 31 and 41 of the second signal switches 3 and 4 are switched from the normally closed contacts 32 and 42 to the normally open contacts 33 and 43, and the first alarm device 61 is made inoperative, and the second or third contact is made. Notification device 6
Operate 2, 63.

In the above-described embodiment, the first or second signal switch 3 or 4 is a break alarm switch or a leak alarm switch. However, for example, an auxiliary switch that switches in conjunction with the opening / closing of the electrical circuit contact 22 or It may be a pre-alarm switch that informs before the circuit breaker is forced to open the circuit breaker, and the common contact is normally closed in response to the operating condition of the circuit breaker or the electric supply condition of the circuit. Any signal switch can be used as long as it is a signal switch for switching from the contact to the normally open contact.

[0016]

As described above, according to the external notification device of the circuit breaker of the present invention, the common contact of one of the at least two types of signal switches is connected to the normally closed contact of the other signal switch, and Connect the normally closed contact of one signal switch, the normally open contact of one signal switch, the normally open contact of the other signal switch, and the common contact of the other signal switch to the normally closed signal terminal, one normally open signal Since it was led out to the outside as a terminal, the other normally open signal terminal, and the common signal terminal,
In the normal state, the normally closed signal terminal is closed to the common signal terminal, each normally open signal terminal is opened, and when at least one of the one and the other signal switch is operating, it is normally closed to the common signal terminal. The signal terminal opens and the normally open signal terminal on the side that operated operates to close, and at least two types of signal switches operate externally from the individual normally open signal terminal, normally closed signal terminal, and common signal terminal. It is possible to transmit a signal of the state, and it is possible to simplify the wiring work by reducing the number of signal lines leading to the outside.

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing an embodiment of the present invention.

[Explanation of symbols]

 1 Electric Circuit 2 Circuit Breaker 21 Handle 22 Electric Circuit Contact 23 Current Detector 24 Switching Mechanism 25 Zero Phase Current Transformer 26 Leakage Detection Circuit 3 First Signal Switch 31 Common Contact 32 Normally Closed Contact 33 Normally Open Contact 4 Second Signal switch 41 Common contact 42 Normally closed contact 43 Normally opened contact 51 Normally closed signal terminal 52 Normally opened signal terminal 53 Normally opened signal terminal 54 Common signal terminal 61 First alarm device 62 Second alarm device 63 Third alarm device

Claims (1)

[Claims] 1. A circuit breaker that opens and closes an electric circuit in response to a steering wheel operation and forcibly opens the electric circuit when an excessive current flows, in response to an operating state of the circuit breaker or an electric supply state of the electric circuit. Store at least two types of signal switches that switch the common contact from the normally closed contact to the normally open contact,
In an external notification device of a circuit breaker for transmitting a signal to the outside, a common contact of one signal switch of the at least two types of signal switches is connected to a normally closed contact of the other signal switch, and further one signal switch. Normally closed contact of
The normally open contact of one signal switch, the normally open contact of the other signal switch, and the common contact of the other signal switch are the normally closed signal terminal, the one normally open signal terminal, the other normally open signal terminal, and the common An external alarm device for a circuit breaker, which is led out to the outside as a signal terminal.