CN102684158A

CN102684158A - Overheat delay protection device for motor

Info

Publication number: CN102684158A
Application number: CN2012101737675A
Authority: CN
Inventors: 赵树元
Original assignee: XIANGYUAN SHUYUAN ELECTRICAL APPLIANCE CO Ltd
Current assignee: XIANGYUAN SHUYUAN ELECTRICAL APPLIANCE CO Ltd
Priority date: 2012-05-31
Filing date: 2012-05-31
Publication date: 2012-09-19

Abstract

The invention discloses an overheat delay protection device for a motor, belonging to the technical field of motor control. The technical problem to be solved is to provide a protection device for controlling overheat delay shutdown of the motor. The adopted technical scheme is that the wire outlet end of a knife switch DK1 is sequentially connected with a main contact CJ1-3 of an alternating current contactor CJ1 and a thermal protector RJ1 in series and then is connected with the power end of the motor M1; the wire inlet end of a normally open contact RJ1-1 of the thermal protector RJ1 is connected with the wire inlet end of a start button AQ1, and the wire outlet end of the normally open contact RJ1-1 of the thermal protector RJ1 is connected with a coil SJ1-1 of a time relay SJ1 in series and then is connected with the wire inlet end of a normally closed contact ZJ1-2 of the middle relay ZJ1. The overheat delay protection device is suitable for the fields such as factories and coal mine.

Description

The motor overheating delay protection device

Technical field

Motor overheating delay protection device of the present invention belongs to the electric machines control technology field, is specifically related to a kind of protective device that the motor overheating time-delay is shut down that is used to control.

Background technology

The overload protection mode that present motor generally adopts is that thermal protector is connected in the motor end of incoming cables, behind the generation overcurrent, and the thermal protector action; Cut off the motor main circuit, reach the purpose of protection motor, the benefit of this protected mode is a reliable in action; Sensitivity is higher, but shortcoming is also a lot, and greatest problem is often to be prone to cause the mistake protection; Particularly at full capacity during long-play, protector is prone to misoperation to equipment, causes equipment fault out of service.

Summary of the invention

The present invention overcomes the deficiency that prior art exists, and technical problem to be solved is: a kind of protective device that the motor overheating time-delay is shut down of controlling is provided.

For solving the problems of the technologies described above, the technical scheme that the present invention adopted is: the motor overheating delay protection device comprises: push-button switch, A.C. contactor, the time relay, thermal protector, auxiliary relay and indicator light;

The main contacts CJ1-3 of A.C. contactor CJ1, its coil CJ1-1, normally opened contact CJ1-2;

The coil SJ1-1 of time relay sj 1, its time-delay normally opened contact SJ1-2;

The normally opened contact RJ1-1 of thermal protector RJ1;

The coil ZJ1-1 of intermediate relay ZJ 1, its normally-closed contact ZJ1-2;

In motor M 1 main circuit, the end of incoming cables of knife switch DZ1 links to each other with three-phase alternating-current supply, links to each other with the power end of motor M 1 behind the main contacts CJ1-3 that the leading-out terminal of knife switch DZ1 is connected in series A.C. contactor CJ1 successively and the thermal protector RJ1;

In the control circuit: the end of incoming cables of fuse RD1 links to each other with the power end of control circuit is anodal; The leading-out terminal of fuse RD1 links to each other with the end of incoming cables of fuse RD2 after being connected in series the normally-closed contact ZJ1-2 of coil CJ1-1, intermediate relay ZJ 1 of stop button AT1, start button AQ1, A.C. contactor CJ1 successively, and the leading-out terminal of fuse RD2 links to each other with the power end negative pole of control circuit;

The normally opened contact CJ1-2 of said A.C. contactor CJ1 is attempted by the two ends of start button AQ1, and the two ends of the coil CJ1-1 of said A.C. contactor CJ1 also are connected to indicator light HD1;

The end of incoming cables of the normally opened contact RJ1-1 of said thermal protector RJ1 links to each other with the end of incoming cables of start button AQ1; Link to each other with the end of incoming cables of the normally-closed contact ZJ1-2 of intermediate relay ZJ 1 behind the coil SJ1-1 of the leading-out terminal of the normally opened contact RJ1-1 of thermal protector RJ1 serial connection time relay sj 1, the two ends of the coil SJ1-1 of said time relay sj 1 also are connected to indicator light HD2;

The end of incoming cables of the time-delay normally opened contact SJ1-2 of said time relay sj 1 links to each other with the end of incoming cables of start button AQ1, links to each other with the end of incoming cables of the normally-closed contact ZJ1-2 of intermediate relay ZJ 1 behind the coil ZJ1-1 of the leading-out terminal of the time-delay normally opened contact SJ1-2 of time relay sj 1 serial connection intermediate relay ZJ 1.

The beneficial effect that the present invention compared with prior art has is: the present invention has added the deferred action device in the motor thermal protection control circuit, and when thermal protector moved, main circuit can not cut off the power supply at once; Continue operation, reach the delay time of setting after, the protective device action; Cut off main circuit, the protection motor, electric current recovers normally between time delay; Thermal protector resets, and then motor can be not out of service, guaranteed the motor reliability of operation; The misoperation of the protector of avoiding, entire circuit is simple for structure, and is practical.

Description of drawings

Do further detailed explanation below in conjunction with the accompanying drawing specific embodiments of the invention:

Fig. 1 is the main circuit diagram of motor among the present invention;

Fig. 2 is the control circuit figure of motor among the present invention.

Embodiment

As depicted in figs. 1 and 2, motor overheating delay protection device of the present invention comprises: push-button switch, A.C. contactor, the time relay, thermal protector, auxiliary relay and indicator light;

The normally opened contact RJ1-1 of thermal protector RJ1;

The coil ZJ1-1 of intermediate relay ZJ 1, its normally-closed contact ZJ1-2.

In motor M 1 main circuit, the end of incoming cables of knife switch DZ1 links to each other with A, B, C three-phase alternating-current supply, links to each other with the power end of motor M 1 behind the main contacts CJ1-3 that the leading-out terminal of knife switch DZ1 is connected in series A.C. contactor CJ1 successively and the thermal protector RJ1.

In the control circuit: the end of incoming cables of fuse RD1 links to each other with the power end of control circuit is anodal; The leading-out terminal of fuse RD1 links to each other with the end of incoming cables of fuse RD2 after being connected in series the normally-closed contact ZJ1-2 of coil CJ1-1, intermediate relay ZJ 1 of stop button AT1, start button AQ1, A.C. contactor CJ1 successively; The leading-out terminal of fuse RD2 links to each other with the power end negative pole of control circuit, the power end of above-mentioned control circuit can with knife switch DZ1 leading-out terminal three-phase AC line in any two link to each other.

When needs starter motor M1, press start button AQ1, the coil CJ1-1 of A.C. contactor CJ1 gets electric, and indicator light HD1 is bright, and its normally opened contact CJ1-2 is closed, and main contacts CJ1-3 is closed, and motor M 1 main circuit must be established beginning work by cable; When needs are closed down motor M 1, press stop button AT1, the coil CJ1-1 dead electricity of A.C. contactor CJ1, indicator light HD1 goes out, and its normally opened contact CJ1-2 breaks off, and main contacts CJ1-3 breaks off, and motor M 1 main circuit dead electricity quits work.

When overcurrent takes place in motor M 1 in running, thermal protector RJ1 action, the normally opened contact RJ1-1 of thermal protector RJ1 is closed; The coil SJ1-1 of time relay sj 1 gets electric, and this moment, motor M 1 meeting continued operation, and the delay time of relay SJ1 arrives when the time; The time-delay normally opened contact SJ1-2 of time relay sj 1 is closed, and the coil ZJ1-1 of intermediate relay ZJ 1 gets electric, and its normally-closed contact ZJ1-2 breaks off; Cut off main circuit, protection motor M 1; If electric current recovers normal between time delay, thermal protector RJ1 resets, and then motor M 1 can be not out of service; Guaranteed motor M 1 reliability of operation, simultaneously, if between time delay; Electric current surpasses set point all the time; Then protective device moves, and has protected the safety of motor M 1, the misoperation of the protector of avoiding.

Claims

1. the motor overheating delay protection device comprises: push-button switch, A.C. contactor, the time relay, thermal protector, auxiliary relay and indicator light;

The normally opened contact RJ1-1 of thermal protector RJ1;

The coil ZJ1-1 of intermediate relay ZJ 1, its normally-closed contact ZJ1-2;

It is characterized in that: in motor M 1 main circuit, the end of incoming cables of knife switch DZ1 links to each other with three-phase alternating-current supply, links to each other with the power end of motor M 1 behind the main contacts CJ1-3 that the leading-out terminal of knife switch DZ1 is connected in series A.C. contactor CJ1 successively and the thermal protector RJ1;