JPH08115838A - Current-transformer apparatus - Google Patents

Abstract

PURPOSE: To provide a current-transformer apparatus which does not depend on the number of a current-transformation ratio, whose large size is avoided and in which an operation to change the current-transformation ratio is simpli fied. CONSTITUTION: Out of a plurality of taps 7a to 7n which are derived from a secondary winding 5, the tap 7a which is derived from one end part of the secondary winding is connected to one terminal board 8. The other taps 7b to 7n are connected to respective sliding contacts 13b to 13n for a rotary switch 12. A rotor 14 for the rotary switch 12 is connected to one terminal board 5. Both terminal boards 8, 15 are connected to secondary interconnections 10, 11. A current-transformation ratio is changed over by the rotary switch 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current transformer device.

[0002]

2. Description of the Related Art In a current transformer, a configuration in which a primary conductor is passed through an iron core of a closed magnetic circuit and a secondary winding is wound around legs of the iron core is already well known. In such a current transformer, in order to be able to switch its current ratio,
A plurality of taps are drawn from a secondary winding, and the taps are selected and connected to a secondary wiring.

FIG. 2 shows the conventional structure, 1 is a base frame, 2
Is a main body of a current transformer, which is mainly constituted by a core 3 of a closed magnetic circuit, a primary conductor 4 penetrating a window of the core 3, and a secondary winding 5 wound on a core leg of the core 3. Are supported on a base frame 1. Primary conductor 4 is base frame 1
, Through a through hole 6 formed at a location corresponding to the window of the iron core 3.

A plurality of taps 7a to 7n are drawn from different positions of the secondary winding 5 for switching the current transformer ratio, and the taps 7a to 7n are selected from these taps to connect a secondary wiring. . For this reason, in the conventional configuration shown in FIG.
a to 8n, and a secondary wiring 10 is connected to a terminal block 8a to which a tap 7a pulled out from one end of the secondary winding 5 is connected, and this secondary wiring is used as a common secondary wiring. And the other terminal blocks have secondary wiring 1 according to the desired current transformation ratio.
1 is selected and connected.

However, according to such a conventional configuration, as the number of current transformer ratios increases, a larger number of terminal blocks need to be installed, and the occupied area of the terminal blocks is increased. Become In addition, every time the current ratio is switched, the secondary wiring must be switched and connected to the terminal block, which is troublesome.

[0006]

DISCLOSURE OF THE INVENTION The present invention aims at avoiding an increase in size of a current transformer device without depending on the number of current ratios, and at the same time simplifies the work for changing the current ratios. With the goal.

[0007]

According to the present invention, among a plurality of taps drawn from a secondary winding, a tap drawn from one end of a secondary winding is connected to one terminal block,
Another tap is connected to each sliding contact of the rotary switch, a rotator of the rotary switch is connected to another terminal block, and secondary wiring is connected to both terminal blocks.

[0008]

When switching the current transformation ratio, the rotor of the rotary switch may be rotated to make contact with a sliding contact connected to a tap matching the desired current transformation ratio. Therefore, the switching connection to the terminal block of the secondary wiring is not necessary for switching the current change ratio. Further, since the terminal switch is composed of two terminal blocks and the rotary switch, it is not necessary to install the terminal blocks in a number corresponding to a required current conversion ratio, and the apparatus can be downsized.

[0009]

Embodiment An embodiment of the present invention will be described with reference to FIG. In addition, the same reference numerals as those in FIG. 2 indicate the same or corresponding portions. According to the present invention, a tap 7 a drawn from one end of the secondary winding 5 is connected to one terminal block 8. The other taps 7b to 7n are used for the rotary switch 1
2 is connected to each of the sliding contacts 13b to 13n. The rotator 14 of the rotary switch 12 is connected to another terminal block 15. The secondary glands 10, 11 are connected to the terminal blocks 8, 15, respectively. The rotary switch 12 is supported by the base frame 1 together with the terminal blocks 8 and 15.

In the above configuration, when switching the current transformation ratio, the rotator 14 of the rotary switch 12 is rotated to change the sliding contacts 13b to 1b in accordance with the desired current transformation ratio.
3n may be brought into contact with one of them. As a result, a secondary current according to the desired current ratio is output between the secondary wires 10 and 11. Switching of the current transformation ratio is only required to rotate the rotator 14 of the rotary switch 12, and the switching operation is simple.

On the other hand, only two terminal blocks and a rotary switch are required to switch the current change ratio.
Unlike the conventional configuration, the number of terminal blocks corresponding to the number of switching of the current change ratio is not required. Therefore, the area required for these installations may be smaller than the conventional configuration. Therefore, such a product can be sufficiently reduced in size.

[0012]

As described above, according to the present invention, it is possible to reduce the size of a current transformer that requires switching of the current-changing ratio as compared with the conventional configuration, and work for switching the current-changing ratio. There is an effect that the simplification can be achieved.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a front view of a conventional configuration.

[Explanation of symbols]

 1 Base Frame 2 Current Transformer 3 Iron Core 4 Primary Conductor 5 Secondary Winding 7a-7n Tap 8 Terminal Block 10 Secondary Wiring 11 Secondary Wiring 12 Rotary Switch 13b-13n Sliding Contact 14 Rotator 15 Terminal Block

Claims (1)

[Claims] 1. A current transformer is constituted by an iron core through which a primary conductor penetrates, and a secondary winding wound around the iron core and having a plurality of taps drawn out from the secondary winding. Of the plurality of taps drawn out, the tap drawn out from one end of the secondary winding is connected to one terminal block, and the other taps are connected to respective sliding contacts of the rotary switch, and A current transformer device comprising a rotary switch rotator connected to another terminal block, and secondary wiring connected to both of the terminal blocks.