CN104459224B - Special joint for measuring handcart circuit breaker contact resistance - Google Patents

Abstract

The invention discloses a kind of special joint for measuring handcart circuit breaker contact resistance, including Plug Division and Handheld Division；Plug Division is made up of insulating base frame and two panels conductive copper sheet, and two panels conductive copper sheet is axially distributed along insulating base frame；Handheld Division is an insulation cover body, and insulation cover body front end is fixed on Plug Division rear end, there is exit be connected respectively with two conductive copper sheets of Plug Division, for fixing cable in insulating boot body；Plug Division conductive copper sheet outside is provided with the scalable insulating sheath of corrugated tube shape.Measurement result deviation of the present invention is small, high precision, can also avoid fastening spring from deforming or intensity decline, improves equipment safety performance.

Description

Special connector for measuring contact resistance of handcart circuit breaker

technical field

The invention relates to a special tool for testing a handcart circuit breaker, in particular to a special joint for measuring the contact resistance of a handcart circuit breaker.

Background technique

At present, handcart circuit breakers are more and more widely used in medium and low voltage power systems. The contact resistance measurement of the handcart circuit breaker is a test to check the contact between the dynamic and static contacts in the arc extinguishing chamber of the handcart circuit breaker, which is very important in the test of the handcart circuit breaker. When measuring the contact resistance of the handcart circuit breaker, the common method is to divide the four terminal clips into two groups, clamp the upper and lower contacts of the circuit breaker respectively, and connect the other ends of the terminal clips to the measuring instrument The positive and negative terminals of the current output terminal and the positive and negative terminals of the voltage input terminal, the measuring instrument outputs a large current (usually 100A or 200A), measures the input voltage, and then calculates the measurement resistance. The design structure and quality of its terminal clip are the main factors affecting the measurement results. In production, there are often large deviations in measurement results caused by poor quality of wiring clips, which seriously affects equipment safety and work efficiency.

At the same time, since the connecting parts of the upper and lower contacts of the handcart circuit breaker are plum-shaped contacts, when the contact fingers of the plum-shaped contacts are clamped by the wiring clip, it is very easy to clamp the clamping spring of the contact, and the large output during measurement The electric current may partly flow through the clamping spring, causing the clamping spring to heat up, lose its strength or deform. During normal operation, the contact resistance between the moving contact of the connected handcart and the static contact of the switch cabinet will increase. In severe cases, the spring will break and cause the moving and static contacts to detach, arcing or even seriously burn the equipment, affecting the safe operation of the equipment. and safe and reliable power supply.

Contents of the invention

The purpose of the present invention is to solve the above problems and provide a special joint for measuring the contact resistance of the handcart circuit breaker, which can not only improve the accuracy of the measurement, but also prevent the clamping spring of the plum blossom contact from decreasing or deforming, and improve the performance of the equipment. safety performance.

The present invention adopts the following technical solutions, including: a plug-in part connected with the plum blossom contact of the circuit breaker and a hand-held part for holding; the plug-in part consists of a cylindrical insulating seat body and a cylinder attached to the insulating seat body The two outer walls on the surface are composed of arc-shaped conductive copper sheets. The two conductive copper sheets are distributed along the axial direction of the insulating seat body and are isolated from each other. The inner diameter fits when the head opens normally; the hand-held part is an insulating cover, and the front end of the insulating cover is fixed on the rear end of the plugging part. The lead-out end of the fixed cable is provided with an insulating layer between the two lead-out ends, and a through hole for the cable to enter is opened at the rear end of the insulating cover; a bellows-shaped flexible insulating sheath is provided on the outside of the conductive copper sheet of the plug-in part to insulate The end of the sheath is fixed on the insulating cover of the handle. The two conductive copper sheets on the plug-in part are electrically connected to the output high current terminal and the input voltage terminal of the instrument respectively. When the plug-in part is inserted into the plum blossom contact of the circuit breaker, the two conductive copper sheets can replace the two The clamps are tested.

Further, there is a protrusion extending between the two conductive copper sheets on the insulating base of the plug-in part.

Further, the insulating cover of the handle part is divided into front and rear parts, and the front and rear cover parts are connected by threads.

Preferably, the arc length of the conductive copper sheet used as the current input and output electrodes on the socket part is not less than 3/4л.

The beneficial effects of the present invention are:

(1) The plug-in part of the special joint is embedded in the plum blossom contact of the circuit breaker, so that the conductive copper sheet is in close contact with the contact, the electrical conductivity is good, and the deviation of the measurement result is small.

(2) A bellows-shaped stretchable insulating sheath is set outside the plug-in part, which can prevent the outer surface of the conductive copper sheet from being damaged by collision or friction with other objects, improve the test accuracy, and enable the special joint to be used repeatedly for many times.

(3) The conductive copper sheet used as the current input and output electrodes on the socket part has a long arc length and a large conductive area, which can effectively reduce the contact resistance between the current conductor layer and the contactor of the handcart circuit breaker, making the measurement error smaller, The measurement results are more precise.

(4) The test current will not pass through the clamping spring outside the plum blossom contact, so the clamping spring can be protected from deformation or strength decline, which improves the safety performance of the equipment.

(5) The special joint and the plum blossom contact are connected by plugging, which is convenient and quick to operate, which brings great convenience to the maintenance and test personnel and can improve the work efficiency.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the present invention.

FIG. 2 is a top view of FIG. 1 .

Fig. 3 is a sectional view along line A-A of Fig. 1 .

Fig. 4 is a circuit connection diagram of the present invention in a test state.

The meanings of the marked symbols in the figure are as follows:

1, 2—conductive copper sheet 11, 12—lead end 12, 22—plane section 13, 23—cable

3—insulation seat body 31—insulation layer 32—boss 33—protrusion

4—Insulation sheath

5-insulation cover 51-front cover part 52-rear cover part 53-end face 54-through hole 55-screw

6 - splint 7 - screw

8 - handcart circuit breaker 81 - upper contact 82 - lower contact

9 - contact resistance tester 91, 93 - positive pole 92, 94 - negative pole

B, C - special connector

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in Figures 1, 2 and 3, the present invention includes a plug-in part connected with a circuit breaker plum-blossom contact and a hand-holding part for holding.

The socket part is composed of a cylindrical insulating base body 3 and two conductive copper sheets 1 and 2 with circular arc-shaped outer walls attached to the cylindrical surface of the insulating base body 3 . The middle of the insulating seat body 3 can be solid or hollow. The two conductive copper sheets 1 and 2 are respectively used as current and voltage input or output electrodes electrically connected to the plum blossom contacts of the circuit breaker. The two conductive copper sheets 1 and 2 are distributed along the axial direction of the insulating seat body 3 and are isolated from each other. There is a protrusion 33 extending between the two conductive copper sheets 1 and 2 on the insulating base body 3 to insulate and separate the two conductive copper sheets 1 and 2. Among them, the arc length of the conductive copper sheet 1 used as the current input and output electrodes is not less than 3/4л. The outer diameter of the insulating seat body 3 attached to the conductive copper sheets 1 and 2 is matched with the inner diameter of the breaker plum blossom contact at a normal opening angle, so that the plum blossom contact can be closely contacted with the contact after being inserted.

The handle part is an insulating cover body 5, and the front end of the insulating cover body 5 has an end face 53 for being fixedly connected with the rear end of the socket part, and the two conductive copper sheets 1, 2 have a bent plane section at the rear end of the socket part 12, 22, the plane section 12, 22 is partly opened with one or several through holes, and the bottom of the insulating base body 3 has a boss 32 extending into the through hole, and the end surface of the front end of the insulating cover body is fixed by the screw 55 through the boss 32. 53 is fixed on the insulating seat body 3. The inner sides of the plane sections 12 and 22 of the two conductive copper sheets have lead-out ends 11 and 21 that are bent into the inner cavity of the insulating cover body 5, and there is a connection between the two lead-out ends 11 and 21 that is connected to the bottom of the insulating base body 3. Insulation layer 31, two lead-out ends 11,21 bottoms are respectively provided with locking screw 7 and splint 6 for fixing cables 13,23, insulation cover body 5 rear end has through hole 54 for cables 13,23 to enter.

A bellows-shaped flexible insulating sheath 4 is arranged on the outside of the conductive copper sheets 1 and 2 of the plug-in part, and the end of the insulating sheath 4 is fixed on the front end of the insulating cover body 5 of the hand-held part.

Considering the convenience of fixing the cables 13, 23, the insulating cover body 5 can adopt a split type, that is, the insulating cover body is divided into front and rear parts, and the front and rear cover body parts 51, 52 are connected by threads.

When testing with the present invention, as shown in Figure 4, select two special connectors B, C, respectively with the upper and lower contacts 81,82 of the handcart circuit breaker 8 plug. Wherein, the two current input or output conductive copper sheets of the special connectors B and C are the conductive copper sheets 1 in Fig. 1 respectively connected to the positive and negative poles 91 and 92 of the large current output end of the contact resistance testing instrument 9 through cables; The two voltage input or output conductive copper sheets of B and C, that is, the conductive copper sheet 2 in Fig. 1 are connected to the positive and negative poles 93, 94 of the voltage output terminal of the contact resistance testing instrument 9 through cables respectively. When the handcart circuit breaker 8 is in the closed state, the contact resistance measurement between the contacts 81 and 82 in the arc extinguishing chamber can be realized by operating the contact resistance measuring instrument 9 .

Claims (4)

1. A special connector for measuring the contact resistance of a handcart circuit breaker, which is characterized in that it includes: a plug-in part connected to the plum blossom contact of the circuit breaker and a hand-held part for holding; the plug-in part is insulated by a cylindrical The base (3) and two conductive copper sheets (1, 2) with circular arc-shaped outer walls attached to the cylindrical surface of the insulating base are composed of two conductive copper sheets (1, 2) along the insulating base (3). ) are axially distributed and separated from each other, and the outer diameter of the insulating seat (3) attached to the conductive copper sheet (1, 2) matches the inner diameter of the circuit breaker plum blossom contact at the normal opening angle; the handle part is an insulating The cover body (5), the front end of the insulating cover body (5) is fixed on the rear end of the plug-in part, and there are two conductive copper sheets (1, 2) respectively connected to the plug-in part in the insulating cover body (5). The lead-out (11,21) of fixed cable (13,23), be provided with insulating layer (31) between two lead-outs (11,21), insulation cover body (5) rear end has for cable (13,21). 23) The through hole (54) that enters; the outer side of the conductive copper sheet (1, 2) of the plug-in part is provided with a bellows-shaped flexible insulating sheath (4), and the end of the insulating sheath (4) is fixed on the insulation of the hand-held part. on the cover body (5). 2. The special joint for measuring the contact resistance of the handcart circuit breaker according to claim 1, characterized in that: there are two conductive copper sheets (1, 2) on the insulating base (3) of the plug-in part protrusions (33) between them. 3. The special connector for measuring the contact resistance of the handcart circuit breaker according to claim 1, characterized in that: the insulating cover (5) of the hand-held part is divided into front and rear parts, and the front and rear cover parts (51 , 52) connected by thread. 4. The special connector for measuring the contact resistance of the handcart circuit breaker according to claim 1, 2 or 3, characterized in that: the arc length of the conductive copper sheet (1) used as the current input and output electrodes on the socket part is not Less than 3/4л.