JPH0110842Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a circuit breaker having a built-in semiconductor relay as an overcurrent trip element.

FIG. 1 is a perspective view of a conventional shingle breaker of this type, and FIG. 2 shows the circuit configuration. In both drawings, a switching mechanism section 3 is provided for each phase between a power supply side terminal 1 and a load side terminal 2, and this switching mechanism section 3 is tripped by a tripping coil 4. The current of each phase flowing to the load side via the load side terminal 2 is detected by the current transformer 5, and the current reduced to the order of milliamperes flows to the semiconductor relay section 7 via the relay terminal block 6. When the current of any one of the phases passing through the circuit breaker exceeds a predetermined value, the semiconductor relay section 7 generates a trigger signal to the tripping coil 4 after a certain delay time, and the switching mechanism section 3 is activated and the fault current is briefly cut off.

In order to perform a field test on such a device, remove the lead wire 8 of any one phase of the relay terminal block 6, connect the test power supply, and apply a test current calculated from the current transformation ratio. It was designed to check the tripping characteristics of the disconnector.

Conventional cable disconnectors such as those described above generally require removing the lead wire 8 from the current transformer 5 during a field test, and there is a risk of making a mistake in wiring after the field test, resulting in poor workability. .

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional ones, and provides a highly reliable shingle breaker that is easy to work with.

An embodiment of this invention will be described below with reference to the drawings. In FIG. 3, a relay terminal block 6 is built into the disconnector, and a part of the cover 9 is provided with a window hole 9a for the relay terminal block. 10 is a cover for the relay terminal block, which is attached to the cover 9 with machine screws 11. 12 is a shorting bar, as shown in FIG. 7, one end is provided with a closed elongated hole 12a,
The other end is provided with a U-shaped groove or notch hole 12b,
Both are connected by an L-bent portion 12c. Then, as shown in FIG. 5, the lead wire 8 is
It is connected to the back side of the relay terminal block 6, and on the front side, as shown in FIG. 4, the shorting bars 12 are screwed to mutually adjacent terminal fittings.

Incidentally, FIG. 4 shows the circuit configuration in this invention. In FIG. 4, current flows from the power supply side terminal 1 to the load side terminal 2 via the load side terminal 2. The current of each phase flowing to the load side is detected by the current transformer 5, and the current reduced to the order of milliampere is transferred to the relay terminal block 6.
The signal flows to the semiconductor relay section 7 via the . If the current in any of the phases passing through the circuit breaker exceeds a predetermined value, the semiconductor relay unit 7 generates a trigger signal to the tripping coil 4 after a certain delay time, and the switching mechanism unit 3 operates. The fault current is then cut off.

When performing a field test, remove the relay terminal block cover 10, then loosen the tightening screw of the shorting bar 12 of any one phase and move the shorting bar 12 in the direction of pulling it out as shown in Fig. 6. , the connection between the current transformer 5 and the semiconductor relay 7 is released. Next, when a test power supply is connected to either terminal UA-UB, VA-VB or WA-WB and a test current calculated from the current transformation ratio of current transformer 5 is applied, the semiconductor relay 7 triggers a specified trip. After a time delay, a trigger signal is generated and the opening/closing mechanism 3 is activated by the tripping coil.

In the above embodiment, the relay terminal block is built into the breaker, but the same effect as in the above embodiment can be obtained even if the terminal block is placed outside the breaker and provided with an insulating cover.

As described above, according to this invention, the relay terminal block 6
Since the shorting bar 12 is provided on the surface of the disconnector, there is no need to remove the lead wire 8 and no need to completely remove the shorting bar 12 during a field test, making the work easier and furthermore, eliminating the need to remove the inside of the disconnector. Since it is built in, it has the effect of providing a small and highly safe product.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional circuit breaker, FIG. 2 is a block diagram showing the circuit configuration of a conventional circuit breaker, and FIG. 3 is a perspective view of the circuit breaker of this invention.
FIG. 4 is a block diagram showing the circuit configuration according to the invention shown in FIG. 3, FIGS. 5 and 6 are structural diagrams of a relay terminal block, and FIG. 7 is a perspective view of a shorting bar. In the figure, 1 is a power supply side terminal, 2 is a load side terminal, 3 is a switching mechanism, 4 is a tripping coil, 5 is a current transformer, 6 is a relay terminal block, 7 is a semiconductor relay, 8 is a lead wire, 9 10 is a cover, 10 is a relay terminal block cover, and 12 is a shorting bar. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A transformer that detects the current flowing between the power supply side terminal and the load side terminal of the breaker, a semiconductor relay section operated by the output of this transformer, a switching mechanism section operated by the output signal of this semiconductor relay section, and the above-mentioned. In a device equipped with a relay terminal block capable of disconnecting and connecting the electric circuit between the transformer and the semiconductor relay section, a shorting bar having a closed hole at one end and a cutout hole at the other end is used as described above. The electrical circuit is connected by screwing the terminal fittings adjacent to each other on the relay terminal block using the closed hole and the cutout hole, and the electrical circuit is disconnected by connecting only the cutout hole side of the shorting bar to the terminal. A circuit breaker or breaker characterized in that it is operated by separating from a metal fitting.