CN2206517Y

CN2206517Y - Automatic coupling decompression starting cabinet for double asynchronous electric motor

Info

Publication number: CN2206517Y
Application number: CN 94235766
Authority: CN
Inventors: 徐鹏青
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-11-11
Filing date: 1994-11-11
Publication date: 1995-08-30
Anticipated expiration: 2004-11-11

Abstract

The utility model provides an automatic coupling decompression starting device which is suitable for the three-phase asynchronous motors of the alternate current 50 hz and the voltage 380V of industrial and mining enterprise. The utility model mainly comprises an automatic coupling transformer, an alternating current contactor, a time relay, a current relay, an intermediate relay, etc. The utility model has the advantages of simple circuit, stable performance, reliable work and convenient maintenance. When the utility model is used, the single automatic coupling transformer can control double motors or multi-motor to realize the decompression starting purpose, so the utilization ratio of the automatic coupling transformer is improved. The switching time of the starting contactor and the running contactor of the utility model is controlled by the relay, and the delay conversion mode of the open circuit is adopted; so the motor harm which is caused by the secondary surge in the starting process of the asynchronous motor can be avoided.

Description

Automatic coupling decompression starting cabinet for double asynchronous electric motor

The utility model provides a kind of and has been applicable to that industrial and mining enterprises exchange 50Hz, voltage 380V three-phase squirrel-cage asynchronous motor is made the not device of frequent reduced voltage starting.

The XJ that China adopts at present ₀₁Series, LZQ serial (the sharp electric power of control principle figure water breakthrough publishing house in 1986 version " the 1173rd, 1176,1177 pages of factory's electric equipment handbook volume two commonly used), JJ ₁Series (the sharp electric power of schematic diagram water breakthrough publishing house one nine nine zero year versions " the 717th, 718,721 pages of factory's electric equipment handbook supplementary copies commonly used) motor self-coupling decompression starting cabinet is single cabinet control separate unit motor, the autotransformer utilance is low, switching time short (in the 0.2S) between starting contactor and the operation contactor, easily making motor produce secondary shoves, impact the motor stator winding, influence motor useful life.

The purpose of this utility model is to provide a kind of confession two platform asynchronous motor decompression starting cabinets, to improve the autotransformer utilance, reduces manufacturing cost, prevents that motor from producing secondary and shoving, and prolongs motor useful life.

The utility model is to realize like this, this starting cabinet comprises shell, button on the shell, indicating device, also comprise the circuit part in the shell, this circuit mainly is made up of autotransformer, A.C. contactor, the time relay, current relay, auxiliary relay etc., increases a starting contactor and an operation contactor respectively and increases a control circuit in addition at control circuit, has realized the starting of separate unit starting cabinet control two motors.In like manner, increase starting contactor and operation contactor again, and increase identical control circuit in addition, can realize the starting of multiple motors.For preventing that producing secondary in the motor starting procedure shoves, the electric current that in the utility model design current relay (KA1, KA2) is passed through discharges when being 1.5 times of motor rated current, relay turn-on time (KT1 or KT2), at this moment, starting contactor (K2 or K5, K1) disconnects, the time relay is through the time-delay of 1-3S, at this moment the generator operation residual voltage of motor has decayed to the motor rated voltage about 0.25 times, and the secondary that this voltage produces shoves and can not produce harm to motor.This starting cabinet can be realized single cabinet control two or multiple motors, and the utilance of autotransformer is improved, and cost reduces, the useful life of having improved motor.

Below in conjunction with description of drawings concrete structure of the present utility model and operation principle.

Accompanying drawing is an electrical schematic diagram of the present utility model.

Two platform motor self-coupling decompression starting cabinets of the utility model comprise shell, button on the shell, indicating device, also comprise the circuit part in the shell, as shown in drawings, this circuit is mainly by autotransformer, A.C. contactor, the time relay, current relay, compositions such as auxiliary relay, it is characterized in that, the three-phase of power supply is respectively by on-load switch QL, fuse FU6, the contact of operation contactor K4, thermal relay RJ2 connects three-phase terminal of motor M2, three-phase terminal of motor M2 also links to each other with the main contacts of starting contactor K5 respectively, the end of incoming cables of K5 links to each other with the leading-out terminal of autotransformer T respectively, in control loop, the normally closed auxiliary contact two ends of starting contactor K5 respectively with the normally-closed contact of contactor K3, the coil of starting contactor K2 links, the coil of often opening auxiliary contact and starting contactor K1 of K5 is cascaded, fuse FU3, FU4 is connected on fuse FU1 respectively, the end of incoming cables of FU2, starting button S3, the normally-closed contact of K4, the normally-closed contact of K2, the coil of K5, the normally-closed contact of time relay KT2 is cascaded, the normally opened contact of K5 is connected in parallel on the S3 two ends, before indicator light HL3 one terminates at the coil of K5, another termination FU4, the normally opened contact of current relay KA2, the coil of auxiliary relay KM2, the normally closed auxiliary contact of K4 is cascaded, the normally opened contact of KM2 is connected in parallel on the normally opened contact of KA2, another normally opened contact of KM2, the normally-closed contact of KA2, the coil of KT2 is cascaded, stop button S4, the timing closing contact of KT2, the coil of K4, the normally-closed contact of thermal relay RJ2 is cascaded, the auxiliary contact of often opening of K4 are connected in parallel on the timing closing contact of KT2, before indicator light HL4 one terminates at the K4 coil, the other end is connected on the FU4, more than each the series connection after circuit all be connected across FU3, on the FU4.Compare with existing motor self-coupling decompression starting cabinet, the utility model has increased (or a plurality of) starting contactor K5 between three-phase terminal that is connected on autotransformer output and other (or many) motor in main circuit, and (or a plurality of) thermal relay RJ2 between other (or many) motor wiring terminal and the power supply, operation contactor K4, fuse FU6.And increase (or a plurality of) control circuit in addition, and promptly in the accompanying drawing, the circuit that FU3, FU4 are following.In FU1, control circuit below the FU2, normally closed auxiliary contact and the Chang Kai auxiliary contact of K5 have been increased.

Operation principle of the present utility model is as follows:

The on-load switch QL that closes presses 1# motor starting button S1, K2 and gets electric adhesive, and HL1 is bright for the starting indicator light, K2 normal opened contact closure, the K1 adhesive, motor M1 begins decompression starting, and the K2 normally closed contact in parallel with KA1 disconnects, under the starting current effect, current relay KA1 action, KA1 normal opened contact closure, auxiliary relay KM1 gets electric adhesive, wherein one group of closed self-sustaining of KM1 normal opened contact, another group KM1 normal opened contact closure performs the preparation of relay K T1 turn-on time.When starting current drops to 1.5 times motor rated current, current relay KA1 discharges, and the KA1 normally closed contact returns, turn-on time relay K T1 loop, the KT1 normally closed contact disconnects, K2, K1 discharge, motor outage, the time-delay through about 2S, the normally open contact closure of KT1 timing closing, operation contactor K3 adhesive, run indicator HL2 is bright, and motor changes the normal operation under the rated voltage over to.The K3 normally closed contact disconnects, and KM1, KT1 successively discharge.

Press stop button S2, K3 contactor outage release, motor is out of service.

Press 2# motor starting button S3, K5, K1 adhesive, indicator light HL3 is bright, motor M2 begins decompression starting, the K5 normally closed contact in parallel with KA2 disconnects, current relay KA2 action, auxiliary relay KM2 adhesive, wherein one group of closed self-sustaining of KM2 normal opened contact, another group normal opened contact KM2 closure performs the preparation of relay K T2 turn-on time.When motor current was reduced to 1.5 times rated current, KA2 discharged, the KT2 adhesive, and K5, K1 discharge, the motor outage, the time-delay through about 2S, KT2 timing closing contact closure, connect operation contactor K4 loop, indicator light HL4 is bright, and motor changes the total head operation over to.The K4 normally closed contact disconnects, and KM2, KT2 successively discharge.

Press stop button S4, the release of K4 contactor, motor shuts down.

Current relay KA1, KA2 carry out electric current to motor respectively and force conversion, and play the restriction autotransformer operating time, the effect of protection transformer.

Between motor starting contactor K2, the K5 electric blocking is arranged, prevent to start simultaneously two motors, the autotransformer capacity is selected according to the separate unit motor capacity.Can need successively start any motor by producing, open, shut down conveniently, not disturb mutually.The power supply of control system is connected on on-load switch QL end of incoming cables, can test, overhaul control circuit under the situation of inoperative motor.

It more than is operation principle explanation of the present utility model, after the capacity of starting cabinet control motor is determined, then optional concrete model of choosing friends stream contactor K1-K5, thermal relay RJ1-RJ2, current relay KA1-KA2, components and parts such as current transformer 1TA-2TA, autotransformer T.

The utility model all has short circuit, the phase failure, overload protection to two (many) platforms motor.

Claims

1, two platform asynchronous motor self-coupling decompression starting cabinets, comprise shell, button on the shell, display device, also comprise the circuit part in the shell, this circuit is mainly by autotransformer, A.C. contactor, the time relay, current relay, auxiliary relay is formed, it is characterized in that, fuse FU6, the contact of operation contactor K4, thermal relay RJ2 connects three-phase terminal of motor M2, three-phase terminal of motor M2 also links to each other with the contact of starting contactor K5 respectively, the end of incoming cables of K5 links to each other with the leading-out terminal of autotransformer T respectively, in control loop, the normally closed auxiliary contact two ends of starting contactor K5 respectively with the normally-closed contact of contactor K3, the coil of starting contactor K2 links, and the coil of often opening auxiliary contact and starting contactor K1 of K5 is cascaded; Fuse FU3, FU4 is connected on fuse FU1 respectively, the end of incoming cables of FU2, starting button S3, the normally-closed contact of K4, the normally-closed contact of K2, the coil of K5, the normally-closed contact of time relay KT2 is cascaded, the normally opened contact of K5 is connected in parallel on the S3 two ends, before indicator light HL3 one terminates at the coil of K5, another termination FU4, the normally opened contact of current relay KA2, the coil of auxiliary relay KM2, the normally closed auxiliary contact of K4 is cascaded, the normally opened contact of KM2 is connected in parallel on the normally opened contact of KA2, another normally opened contact of KM2, the normally-closed contact of KA2, the coil of KT2 is cascaded, stop button S4, the timing closing contact of KT2, the coil of K4, the normally-closed contact of thermal relay RJ2 is cascaded, the auxiliary contact of often opening of K4 are connected in parallel on the timing closing contact of KT2, before indicator light HL4 one terminates at the K4 coil, the other end is connected on the FU4, more than each the series connection after circuit all be connected across FU3, on the FU4.

2, as claimed in claim 1 pair of platform motor self-coupling decompression starting cabinet is characterized in that, the delay time of described time relay KT1, KT2 is 1-3 second.