CN106990377A - A kind of 10kV switch cabinet current transformers test fixture - Google Patents

Abstract

The invention relates to a test fixture for a current transformer of a 10kV switch cabinet, which includes a crank arm, a double-arm clamp is fixed at the front end of the crank arm, a contact is arranged on the head of the clamp, the contact is connected to a test cable, and the rear end of the crank arm is installed. Screw handle. A 10kV switch cabinet current transformer test fixture of the present invention adopts an inverted U-shaped structure, and the inverted U-shaped crank arm is integrally formed of Bakelite with good insulation and easy processing, and has both certain mechanical strength and insulation properties. The front end of the crank arm is a rotatable double-arm clamp that can simultaneously clamp the two primary terminals of the current transformer, reducing the number of test connections. The wire clip is a copper multi-row contact, one end is fixed on the movable shaft, and the other end is supported by a spring, which not only increases the contact area with the primary wiring board of the current transformer, makes it in good contact, but also ensures the passage of large current, and It can increase the fastness of the wire clip, and can be fixed reliably to prevent falling off.

Description

A 10kV switch cabinet current transformer test fixture

technical field

The invention relates to the design of a test fixture for a current transformer of a 10kV switch cabinet.

Background technique

With the widespread application of 10kV switchgear in the national grid power system and large-scale enterprise substations, the test tasks of 10kV current transformers are increasing day by day, and the traditional test methods have problems such as difficult operation and low efficiency. So how to improve the test efficiency and test safety of 10kV current transformer is an urgent problem to be solved. The steps of the traditional test are as follows: 1. The tester puts his hands into the cabinet body to find out the position of the primary side screw; 2. Puts the wire clamp into the cabinet body for blind clamping according to the proven position; 3. Wait for the wire clamp to clamp the pile After tightening the screw, shake the clamp to check whether it is clamped. If the clamp fails, repeat the above operation. The internal space of the cabinet is narrow, only the arm can be extended in, and the screw is in the blind area of vision, which makes the clamping operation difficult, and the clamp is easy to fall off, posing a safety hazard. In addition, due to the short exposure of the pile head screw and the small contact surface, the high current test will cause the test to fail due to the large contact resistance and difficulty in raising the current. Repeated clamping operations are required, which reduces the test efficiency. It can be seen that the structure and operation limitation of the traditional fixture is the main reason for the low test efficiency, and it is necessary to develop a new fixture to replace the traditional fixture, so as to improve the test efficiency.

Contents of the invention

The technical problem to be solved by the present invention is to provide a 10kV switch cabinet current transformer test fixture, which adopts a U-shaped structure and belongs to a general-purpose fixture, which can be used for tests such as the transformation ratio, polarity, and volt-ampere characteristics of the current transformer. It can also be used for current transformer boosting test.

In order to solve the problems existing in the prior art, the technical solution adopted in the present invention is:

A 10kV switch cabinet current transformer test fixture, including a crank arm, a double-arm clamp is fixed at the front end of the crank arm, a contact is arranged on the head of the clamp, the contact is connected to the test cable, and a screw handle is installed at the rear end of the crank arm.

The front end of the crank arm and the double-arm clamp are connected by bolts.

The crank arm is inverted U-shaped.

Described crank arm is made of Bakelite.

The double-arm clamp is rotatable.

The contacts are multi-row contacts, one end is fixed on the movable shaft, and the other end is supported by a spring.

The contacts are made of copper.

An insulating pad is added to the bottom of the screw.

Advantage and effect that the present invention has are:

A 10kV switch cabinet current transformer test fixture of the present invention adopts an inverted U-shaped structure, and the inverted U-shaped crank arm is integrally formed of Bakelite with good insulation and easy processing, and has both certain mechanical strength and insulation properties. The front end of the crank arm is a rotatable double-arm clamp that can simultaneously clamp the two primary terminals of the current transformer, reducing the number of test connections. The wire clip is a copper multi-row contact, one end is fixed on the movable shaft, and the other end is supported by a spring, which not only increases the contact area with the primary wiring board of the current transformer, makes it in good contact, but also ensures the passage of large current, and It can increase the fastness of the wire clip, and can be fixed reliably to prevent falling off. A screw handle is installed at the rear end of the crank arm, and an insulating pad is installed at the bottom to increase friction. The invention belongs to a general-purpose fixture, which can be used not only for tests of transformation ratio, polarity, volt-ampere characteristics and the like of current transformers, but also for current transformer rising tests. The use of this fixture does not require operators to enter the inside of the switch cabinet, which is convenient to use, can greatly improve the test efficiency of current transformers, save test time, reduce the workload of test personnel, and ensure personal safety at the same time. In the clamping process, it has the characteristics of high safety factor, low work intensity, high work efficiency and reduced labor intensity. It can make the disassembly and assembly of the fixture simple and convenient, greatly reduce the time of fixture disassembly and assembly, and can effectively improve the current transformer test of 10kV switchgear. Efficiency, improve the quality of inspection and maintenance work, and ensure the reliability of power supply.

Description of drawings

Fig. 1 is the overall structure schematic diagram of a kind of 10kV switchgear current transformer test fixture of the present invention;

Figure 2 is an enlarged view of the local structure.

Main parts in the figure: crank arm 1, bolt 2, double-armed clamp 3, contact 4, cable 5, screw handle 6, insulating pad 7, movable shaft 8, spring 9.

detailed description

Below in conjunction with accompanying drawing, the present invention is described in further detail:

As shown in Figure 1, a 10kV switch cabinet current transformer test fixture of the present invention includes an inverted U-shaped crank arm 1, and the material of the inverted U-shaped crank arm 1 is integrally formed with Bakelite with good insulation and easy processing. A rotatable double-arm clamp 3 is fixed with a bolt 2 at the front end of the crank arm, and the head of the clamp is a plurality of copper spring contacts 4 . As shown in FIG. 2 , the contacts are multi-row contacts, one end is fixed on the movable shaft 8 , and the other end is supported by a spring 9 . The contact can be connected to the test cable 5 . A screw handle 6 is installed at the rear end of the crank arm, and an insulating pad 7 is installed at the bottom of the screw rod.

When the present invention is in use, the copper contact at the front end is pressed on the wiring aluminum bar of the current transformer, and the rear end is placed on the frame of the switch cabinet. By rotating the handle on the handle, the wire clamp can reliably contact the terminal block of the current transformer, and the clamp is connected to the test instrument through the cable, which is convenient and quick.

Claims (8)

1. A 10kV switch cabinet current transformer test fixture, characterized in that: comprising Knuckle arm, a double-arm clamp is fixed at the front end of the crank arm, and a contact is arranged on the head of the clamp, which is connected to the test cable, and a screw handle is installed at the rear end of the crank arm. 2. A 10kV switch cabinet current transformer test fixture according to claim 1, characterized in that: the front end of the crank arm and the double-arm clamp are connected by bolts. 3. A 10kV switchgear current transformer test fixture according to claim 1 or 2, characterized in that: the crank arm is an inverted U shape. 4. A 10kV switch cabinet current transformer test fixture according to claim 3, characterized in that: said crank arm is made of Bakelite. 5. A test fixture for a 10kV switch cabinet current transformer according to claim 1, characterized in that: said double-arm clamp is rotatable. 6. A 10kV switchgear current transformer test fixture according to claim 1, characterized in that: the contacts are multi-row contacts, one end is fixed on the movable shaft, and the other end is supported by a spring. 7. A 10kV switchgear current transformer test fixture according to claim 1 or 6, characterized in that: said contacts are made of copper. 8. A 10kV switch cabinet current transformer test fixture according to claim 1, characterized in that: the bottom of the screw rod is equipped with an insulating pad.