JPH0636665A - Circuit breaker control device - Google Patents

Abstract

PURPOSE:To facilitate the alteration of setting of a circuit breaker tripping current as the load capacity of facilities increases and to facilitate the maintenance of the circuit breaker in receiving and transforming facilities. CONSTITUTION:A first and second indicator lamp are provided, and a first and second pilot current value and a tripping current value, all of which can be freely set and varied, are set in a control circuit 14. A detected current value is compared with each set current value in the control circuit 14. When the circuit current is in excess of either of the pilot current values, the corresponding indicator lamp 6 or 7 is turned on, whereas when the detected current value is equal to or greater than the tripping current value, the current is tripped to a circuit breaker via an operating circuit 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker control device which trips in response to a circuit current.

[0002]

2. Description of the Related Art When changing the tripping current value of a circuit breaker associated with an increase in the capacity of a circuit breaker accompanying an increase in load capacity of equipment, there is a desire to carry out the plant operation continuously without interruption. There is. However, means for easily realizing such a request has not been established so far, and therefore, every time the setting of the trip current is changed, the plant operation is interrupted, the power is cut off, and the setting is changed. It is the present situation.

[0003]

DISCLOSURE OF THE INVENTION The present invention makes it possible to cope with a change in the setting of the circuit breaker trip current due to an increase in load capacity of equipment without a power failure or plant stoppage. The purpose is to facilitate the maintenance of the vessel.

[0004]

In order to achieve the above object, a circuit breaker control apparatus according to the present invention comprises a first and a second indicator lights and a current detecting means for detecting a current flowing through a main circuit to be protected. And setting means for setting the first monitoring current value, the second monitoring current value, and the tripping current value, and comparing the value of the current detected by the current detecting means with each current value set by the setting means, When the detected current value exceeds the first monitoring current value or the second monitoring current value, the corresponding first or second indicator lamp is turned on, and the detected current value is equal to or greater than the tripping current value. In some cases, a control circuit for issuing a trip command is provided.

[0005]

With the first and second indicator lights, the first monitor current value, the second monitor current value, and the trip current value that can be arbitrarily changed are set, and the detected circuit current is set. Compare with each set current value. If the circuit current exceeds each monitored current value, turn on the corresponding indicator light,
When the detected current value is equal to or greater than the trip current value, a trip command is issued to the circuit breaker. By doing so, it is possible to cope with changes in the load capacity of equipment without power outages or plant shutdowns, facilitate monitoring of circuit current in power receiving and transforming equipment, and facilitate maintenance of power receiving and transforming equipment including circuit breakers. Can be

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in the drawings.

2A and 2B are a front view and a side view, respectively, of a circuit breaker according to the present invention. The first terminal portion 1 is arranged above the case 2A, and the second terminal portion 3 is arranged below the case. A breaking unit (not shown) including a breaking contact is interposed between the terminal units 1 and 2. The blocking portion is brought to the closing position (closing position) by tilting the operation lever 2 arranged at the center of the front surface of the case 2A upward. The operating lever 2 is brought to the lower shut-off position (open position) in conjunction with the automatic tripping of the circuit breaker, and can also be manually set to the open position by unlocking a lock (not shown). A dip switch 4 for setting the tripping current value of the circuit breaker is provided at the bottom. In the case of this embodiment, the dip switch 4 is composed of four unit switches, and among the predetermined 16 kinds (= 2 ⁴ ) of tripping current values, depending on the combination of ON / OFF of these four unit switches. To set the desired trip current value. The DIP switch 4 is provided with a protective cover 5 to prevent erroneous operation. The protective cover 5 is opened by pushing down the claw at the upper center. Indicator lights 6 and 7 are provided to schematically indicate what the current load current flowing through the circuit breaker is. The indicator lights 6 and 7 are composed of, for example, LEDs of appropriate colors. For example,
The indicator light 6 is yellow and the load current flowing through the breaker is the first
Lights when the monitored current value (for example, 50% of the trip current) is exceeded, and the indicator lamp 7 is red and lights when the load current exceeds the second monitored current value (for example, 80% of the trip current).
These monitor current values are set by the monitor current setting switches 8 and 9, respectively. Monitor current setting switch 8,
Reference numeral 9 may be a rotary switch type, and the setting can be appropriately changed in units of 10% of the trip current or the circuit breaker rated current. A trip current value display unit 10 for attaching a sticker indicating the trip current value set by the dip switch 4 is provided below the operation lever 2. FIG. 1 shows a block diagram of the control device portion. A breaking contact 20 is interposed between the two terminal portions 1 and 2. The load current flowing through the breaker including the breaking contact 20 is detected by the current transformer 11. Current transformer 1
The current detected by 1 is guided to the current detection circuit 12, where it is converted into a voltage signal proportional to the current. The analog signal output from the current detection circuit 12 is converted into a digital signal by the A / D conversion circuit 13 and guided to the control circuit 14. A setting signal is also input from the setting unit 15 to the control circuit 14. The setting unit 15 corresponds to the dip switch 4 and the monitoring current setting switches 8 and 9 in FIG. The control circuit 14 monitors the detected current value from the A / D conversion circuit 13, and when it reaches the first monitored current value set by the setting unit 15, the first indicator light 6 included in the display circuit 17 is turned on. Turn on the light. Similarly, when the detected current value reaches the second monitoring current value, the second current included in the display circuit 17 is detected.
The indicator lamp 7 is turned on. Further, when the detected current value reaches the trip current value, the breaking contact 20 is opened via the operation circuit 16 (that is, the breaker is tripped).

As described above, according to the present invention, the current load current value can be easily recognized from the lighting state of the indicator lamp without using a special current measuring device. You can This is very effective in facilitating the maintenance work of the equipment. Further, in many types of equipment, a power failure or plant stop is often at night, and maintenance work itself has to be carried out in an unstable posture in a narrow space. According to the present invention, since it is possible to change the setting of the tripping current value or the like without interruption of power or plant stop, it is possible to avoid the maintenance work under such bad conditions.

[0009]

As is apparent from the above description, according to the present invention, it is possible to cope with a change in the setting of the circuit breaker trip current due to an increase in the load capacity of equipment without a power outage or plant stoppage. The maintenance work of the circuit breaker in the power receiving and transforming facility can be facilitated.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a circuit breaker control device according to the present invention.

2A and 2B are a front view and a side view showing an embodiment of a circuit breaker having a control device of the present invention.

[Explanation of symbols]

 1,3 Terminal part 2 Operation switch 2A Case 4 Dip switch 6,7 Indicator light 8,9 Monitoring current setting switch 11 Current transformer 12 Current detection circuit 13 A / D conversion circuit 14 Control circuit 15 Setting part 16 Operation circuit 17 Display Circuit 20 Breaking contact

Claims (2)

[Claims] 1. A first and a second indicator lamp, a current detecting means for detecting a current flowing through a main circuit to be protected, a first monitoring current value, a second monitoring current value, and a trip current value are set. Comparing the current value detected by the current detecting means with each current value set by the setting means, and the detected current value exceeds the first monitoring current value or the second monitoring current value. Control device for the circuit breaker, which includes a control circuit for illuminating the corresponding first or second indicator lamps respectively, and for issuing a trip command when the detected current value is equal to or greater than the trip current value. . 2. The setting means is capable of setting each set value from outside the breaker case.
The control device described.