Junction box structure of current transformer

Abstract

The utility model discloses a junction box structure of a current transformer. The junction box structure comprises a junction box body, the three first wiring copper bars are fixed at the upper part in the junction box body, and each first wiring copper bar comprises a leading-out end and a leading-in end; the second wiring copper bar is fixed at the lower part in the wiring box body and is staggered with the three first wiring copper bars; the three current transformers are fixed in the junction box body and are vertically arranged between the first wiring copper bar and the second wiring copper bar; the initial end of each stator lead passes through the corresponding current transformer and then is fixedly connected with the leading-out end of the corresponding first wiring copper bar; each neutral point lead passes through the corresponding current transformer and then is fixedly connected with the second connector lug copper bar; the cable is divided into three cable leads at the position of a cable head, and the three cable leads are fixedly connected with the leading-in ends of the corresponding first wiring copper bars respectively. The junction box structure provided by the utility model can solve the problem of difficult wiring.

Description

TECHNICAL FIELD

[0001] The utility model belongs to motor technical field, especially relate to a wiring box structure of current transformer. BACKGROUND

[0002] The current transformer is a product specially designed for the differential protection device of large-capacity motor and is generally applicable to the motor with a capacity greater than 2000kW. The working principle of the current transformer is as follows: the lead lines at the starting end and neutral point end of each phase stator winding of the motor are connected to the magnetic balance transformer, respectively, when the same short circuit or ground fault occurs in the motor, the fault current breaks the magnetic flux balance of the current transformer, and the secondary side generates a current, when the current reaches a specified value, the current relay is started to trip the short circuit breaker in the motor distribution cabinet, and the motor current is cut off, thereby achieving the purpose of protecting the motor.

[0003] As shown in Figure 1 and Figure 2 , the installation structure of the current transformer in the prior art comprises a current transformer 400 horizontally arranged in a wiring box body 100, a first wiring copper bar 200, a second wiring copper bar 300 and a cable 700, wherein the first wiring copper bar 200 and the second wiring copper bar 300 are arranged oppositely, the current transformer 400 is horizontally arranged between the first wiring copper bar 200 and the second wiring copper bar 300, a stator lead line starting end 500 is connected to the lead-out end of the first wiring copper bar 200 after extending out of a motor shell 800, a cable lead line 701 separated from the cable 700 is connected to the lead-in end of the first wiring copper bar 200 after passing through the current transformer 400, and a neutral point lead line 600 extends to the wiring box body 100 through the motor shell 800 and is connected to the second wiring copper bar 300 after passing through the current transformer 400.

[0004] However, since the spacing between the bottom of the wiring box and the current transformer is small, the cable head is made in the wiring box body and then separated into three cable lead lines, and the spacing between the cable and the current transformer is smaller, which leads to difficult field wiring and affects work efficiency. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a wiring box structure of current transformer, and solves the problem of difficult motor power wiring.

[0006] Based on the above problems, the technical scheme provided by the utility model is as follows:

[0007] A wiring box structure of current transformer, comprising:

[0008] A wiring box body, which is hollow inside and fixed on the outer wall of a motor shell;

[0009] Three first wiring copper bars, which are fixed at the upper part in the wiring box body, each first wiring copper bar comprises a lead-out end and a lead-in end;

[0010] a second wiring copper bar fixed in the lower part of the terminal box and staggered with the three first wiring copper bars;

[0011] three current transformers fixed in the terminal box and vertically arranged between the first wiring copper bars and the second wiring copper bar;

[0012] three stator lead beginnings led from the motor shell into the terminal box, each of the stator lead beginnings fixedly connected with the leading end of the corresponding first wiring copper bar after passing through the corresponding current transformer;

[0013] three neutral point leads led from the motor shell into the terminal box, each of the neutral point leads fixedly connected with the second wiring copper bar after passing through the corresponding current transformer;

[0014] a cable extended into the terminal box, the cable separated into three cable leads at the cable head position, the three cable leads fixedly connected with the leading-in ends of the corresponding first wiring copper bars respectively.

[0015] In some embodiments, a support frame is arranged in the terminal box, and the three current transformers are fixed on the support frame.

[0016] In some embodiments, the support frame comprises two first supports symmetrically fixed on the inner wall of the terminal box and oppositely arranged, and two second supports symmetrically arranged between the two first supports, and the current transformers are fixedly connected with the two second supports.

[0017] In some embodiments, the first support and the second support are in inverted L shape.

[0018] In some embodiments, the first support is welded on the inner wall of the terminal box, and the second support and the first support, and the current transformers and the second support are connected by bolts.

[0019] In some embodiments, the first wiring copper bar is fixed in the terminal box by a first insulator assembly.

[0020] In some embodiments, the second wiring copper bar is fixed in the terminal box by a second insulator assembly.

[0021] In some embodiments, the first wiring copper bar is in U shape.

[0022] In some embodiments, the second wiring copper bar is in long strip shape.

[0023] In some embodiments, the cable is fixed to the terminal box by a metal gland.

[0024] Compared with the prior art, the utility model has the advantages of:

[0025] 1、The second wiring copper bar and the three first wiring copper bars are arranged in an up-and-down staggered manner, the current transformer is vertically arranged in the terminal box body, the stator lead start is connected to the outgoing end of the first wiring copper bar after passing through the current transformer, the neutral point lead is connected to the second wiring copper bar after passing through the current transformer, and the cable lead separated from the cable is directly connected to the incoming end of the first wiring copper bar, so that the current transformer does not interfere with the installation of the cable, the installation of the cable is facilitated, and the installation efficiency is improved.

[0026] 2、The current transformer is fixed in the terminal box body through the support frame, the support frame has simple structure, facilitates installation, has good stability, and improves structural strength. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical scheme of the utility model embodiment, the following will be briefly introduced the drawings needed to be used in the embodiment description, the drawings in the following description are only some embodiments of the utility model, for the ordinary skilled in the art, under the premise of not paying the creative labor, still can obtain other drawings according to these drawings.

[0028] Figure 1 It is one of the structural schematic diagrams of the installation structure of the current transformer in the prior art;

[0029] Figure 2 It is the second structural schematic diagram of the installation structure of the current transformer in the prior art;

[0030] Figure 3 It is one of the structural schematic diagrams of the terminal box structure embodiment of the current transformer of the utility model;

[0031] Figure 4 It is the second structural schematic diagram of the embodiment of the utility model;

[0032] Figure 5 It is Figure 4 The local enlarged view of A in the middle;

[0033] Among them:

[0034] 100, terminal box body;200, first wiring copper bar;300, second wiring copper bar;400, current transformer;500, stator lead start;600, neutral point lead;700, cable;701, cable lead;800, motor housing;

[0035] 1, terminal box body;

[0036] 2. First connecting copper busbar;

[0037] 3. Second wiring copper busbar;

[0038] 4. Current transformer;

[0039] 5. Stator lead start;

[0040] 6. Cable; 6-1. Cable lead; 6-2. Cable head;

[0041] 7. Support frame; 7-1. First support; 7-2. Second support;

[0042] 8. Neutral point lead;

[0043] 9. First insulator assembly;

[0044] 10. Second insulator assembly;

[0045] 11. Motor housing;

[0046] 12. Metal gland. Detailed Implementation

[0047] The above solution will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrating the present invention and are not intended to limit the scope of the present invention. The implementation conditions used in the embodiments can be further adjusted according to the conditions of specific manufacturers, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0048] See Figure 3 and Figure 4 The diagram below is a structural schematic of an embodiment of the present utility model, which provides a junction box structure for a current transformer, including a junction box body 1, three first copper busbars 2, two copper busbars 3, three current transformers 4, three stator lead ends 5, three neutral point leads 8, and a cable 6.

[0049] The junction box 1 is hollow inside and fixed to the outer wall of the motor housing 11. Specifically, the bottom plate of the junction box 1 is fixed to the motor housing 11 by multiple bolts.

[0050] Three first copper busbars 2 are fixed in the upper part of the junction box 1. Each first copper busbar 2 includes an outgoing end and an incoming end. Preferably, the first copper busbar 2 is U-shaped and is fixed in the junction box 1 by a first insulator assembly 9. The first insulator assembly 9 includes two first insulators arranged side by side. The first insulators are fixed to a first bracket on the junction box 1 by screws. The first copper busbars 2 are fixedly connected to the first insulators by screws.

[0051] The second wiring copper bars 3 are fixed in the lower part of the terminal box body 1 and are staggered with the plurality of first wiring copper bars 2, that is, the second wiring copper bars 3 are arranged obliquely below the plurality of first wiring copper bars 2, preferably, the second wiring copper bars 3 are in the shape of a long strip and are fixed in the terminal box body 1 through the second insulator subassembly 10, the second insulator subassembly 10 comprises a plurality of second insulators arranged at intervals, the plurality of second insulators are respectively fixed on the second support of the terminal box body 1 through screws, and the second wiring copper bars 3 are fixedly connected with the second insulators through screws.

[0052] Three current transformers 4 are fixed in the terminal box body 2 and are vertically arranged between the first wiring copper bars 2 and the second wiring copper bars 3. In order to facilitate the installation of the current transformers 4, the support frame 7 is arranged in the terminal box body 1, and the three current transformers 4 are fixed on the support frame 7.

[0053] As shown in Figure 5 , the support frame 7 comprises two first supports 7-1 symmetrically fixed on the inner wall of the terminal box body 1 and oppositely arranged, and two second supports 7-2 symmetrically arranged between the two first supports 7-1 and fixedly connected with the current transformers 4. Preferably, the first support 7-1 and the second support 7-2 are both in the shape of an inverted L.

[0054] Among them, the first support 7-1 is welded on the inner wall of the terminal box body 1, and the second support 7-2 and the first support 7-1, and the current transformer 4 and the second support 7-2 are connected through bolts.

[0055] Three stator lead beginnings 5 are led out from the motor shell 11 to the terminal box body 1, and each stator lead beginning 5 is connected with the leading end of the corresponding first wiring copper bar 2 after passing through the corresponding current transformer 4.

[0056] Three neutral point leads 8 are led out from the motor shell 11 to the terminal box body 1, and each neutral point lead 8 is fixedly connected with the second wiring copper bar 3 after passing through the corresponding current transformer 4.

[0057] The cable 6 is extended to the terminal box body 1 through the metal gland 12, and three cable leads 6-1 are separated at the position of the cable head 6-2 of the cable 6, and the three cable leads 6-1 are respectively fixedly connected with the leading-in ends of the corresponding first wiring copper bars 2.

[0058] During field wiring, the single armored cable 6 (three-core) is threaded through the metal gland 12 at the bottom of the terminal box body 1, and after cable head 6-2 is made, the single armored cable 6 is divided into three cable leads 6-1. Since the stator lead start end 5 has been threaded through the current transformer 4 before being fixed to the first wiring copper bar 2, the single cable lead 6-1 does not need to be threaded through the current transformer 4 again, and can be directly fixed to the lead-in end of the first wiring copper bar by using a copper wiring end. At this time, since the size space between the bottom of the terminal box body 1 and the first wiring copper bar 2 is large, the actual field wiring is very convenient.

[0059] In summary, the terminal box structure is compact, convenient to wire, and improves the wiring efficiency.

[0060] The above examples are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent transformation or modification according to the spirit and essence of the present application should be covered within the protection scope of the present application.

Claims

1. A terminal box structure of a current transformer, characterized by comprising: The utility model relates to a motor terminal box, comprising: a terminal box body, which is hollow inside and fixed on the outer wall of a motor shell; three first terminal copper bars, which are fixed in the upper part of the terminal box body, each of the first terminal copper bars comprising an outgoing end and an incoming end; a second terminal copper bar, which is fixed in the lower part of the terminal box body and staggered with the three first terminal copper bars; three current transformers, which are fixed in the terminal box body and vertically arranged between the three first terminal copper bars and the second terminal copper bar; three stator lead initial ends, which are led out from the motor shell into the terminal box body, each of the stator lead initial ends being fixedly connected with the outgoing end of the corresponding first terminal copper bar after passing through the corresponding current transformer; three neutral point leads, which are led out from the motor shell into the terminal box body, each of the neutral point leads being fixedly connected with the second terminal copper bar after passing through the corresponding current transformer; a cable, which extends into the terminal box body, the cable being divided into three cable leads at the cable head position, the three cable leads being fixedly connected with the incoming end of the corresponding first terminal copper bar, respectively.

2. The terminal box structure of a current transformer according to claim 1, characterized by: The terminal box body is provided with a support frame, and the three current transformers are fixed on the support frame.

3. The current transformer terminal box structure according to claim 2, characterized in that: The support frame comprises two first supports fixed symmetrically on the inner wall of the terminal box body and arranged oppositely, and two second supports fixed between the two first supports and arranged symmetrically, and the current transformers are fixedly connected with the two second supports.

4. The current transformer terminal box structure according to claim 3, characterized in that: The first support and the second support are in inverted L shape.

5. The current transformer terminal box structure according to claim 4, characterized in that: The first support is welded on the inner wall of the terminal box body, and the second support is bolted between the first support and the current transformer.

6. The current transformer terminal box structure of claim 1, wherein: The first terminal copper bar is fixed in the terminal box body through a first insulator assembly.

7. The current transformer terminal box structure of claim 1, wherein: The second terminal copper bar is fixed in the terminal box body through a second insulator assembly.

8. The current transformer terminal box structure of claim 1, wherein: The first terminal copper bar is in U shape.

9. The current transformer terminal box structure of claim 1, wherein: The second terminal copper bar is in long strip shape.

10. The terminal box structure of a current transformer according to claim 1, characterized by: The cable is fixed on the terminal box through a metal gland.

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