CN201039050Y

CN201039050Y - Automatic conversion protector of three-phase asynchronous motor

Info

Publication number: CN201039050Y
Application number: CNU200720021643XU
Authority: CN
Inventors: 韩怀德
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-04-29
Filing date: 2007-04-29
Publication date: 2008-03-19
Anticipated expiration: 2017-04-29

Abstract

The utility model relates to a three-phase asynchronous motor automatic conversion protector. The utility model is characterized in that the utility model mainly consists of a main AC contactor QC on an internal circuit board in a shell, a time relay JS, a star-shaped starting AC contactor YC, and a triangle running AC contactor SC; the detailed circuit is that one end of a stop button TA is connected with the A-phase of a three-phase power supply and the other end of the stop button TA is connected with one end of a starting button QA which is connected in parallelism with an AC contactor QC1; the other end of the starting button QA is divided into three ways: one way is sequentially connected with a thermal relay JR, a main AC contactor QC and a C-phase of the power supply; the thermal relay JR is also connected with a power supply neutral line N through a ringer DL; the second way is connected with the triangle running AC contactor SC1, is then connected in series with the time relay JS1 and the star starting AC contactor YC, and is then connected with one end of the time relay JS after connected in parallelism; the other end of the second way is connected with the C-phase of the power supply; the third way is connected with one end of the time relay JS2 and the AC contactor SC2 after connected in parallelism; the other end of the third way is connected with the AC contractor YC1; the AC contactor SC is connected with the C-phase of the power supply. Therefore, the utility model has the advantages of simple structure, low cost, little malfunction, and convenient maintenance.

Description

Automatic switching protector of three phase asynchronous motor

Technical field: the utility model belongs to the starting and the protection field of threephase asynchronous, is specifically related to a kind of automatic switching protector of three phase asynchronous motor.

Background technology: existing threephase motor is across-the-line starting, its starting current can reach the several times of running current, electrical network and distribution equipment are impacted or damage, for reducing the impact of starting current, the general purpose that adopts manual and automatic autotransformer dual mode to reach decompression starting, manual manipulation mode is too backward, and control exists cost height, troublesome shortcoming automatically.

Summary of the invention: the purpose of this utility model provides a kind of simple in structure, and cost is low, and fault is few, automatic switching protector of three phase asynchronous motor easy to maintenance.

The technical solution of the utility model is: a kind of automatic switching protector of three phase asynchronous motor is characterized in that: mainly be made up of main A.C. contactor QC, time relay JS on the wiring board in the housing, star starting A.C. contactor YC and triangle AC contactor SC; Its physical circuit is that the A of stop button TA one termination three phase mains goes up mutually, and the other end connects starting button QA one end, and starting button QA is in parallel with A.C. contactor QC1; The starting button QA other end joins with the C of power supply after dividing three the tunnel, the one tunnel to meet thermal relay JR, main A.C. contactor QC successively, and thermal relay JR also meets power supply neutral line N through electric bell DL; The second the tunnel meets triangle AC contactor SC1, connects with time relay JS1, star starting A.C. contactor YC to join with a end after time relay JS is in parallel again, and the C of its another termination power joins mutually; Third Road joins with a end after time relay JS2 and A.C. contactor SC2 are in parallel, and its another termination A.C. contactor YC1, A.C. contactor SC join with the C of power supply.

The B that connects power supply after wherein said three road ends connect power supply indicator HD, A.C. contactor QC2 series connection and working station indicator LD, A.C. contactor QC3 connect goes up mutually.

Because adopt technique scheme, when motor starting, it is connected into star with the winding of motor, starting current only is equivalent to 1/3rd of normal starting electric current, has reduced the impact to electrical network and distribution equipment effectively, reaches the purpose of decompression starting; When the starting current of motor no longer fell after rise, it can be connected into triangle to the winding of motor automatically, makes motor enter normal operating conditions.Thereby have simple in structurely, and cost is low, and fault is few, advantage easy to maintenance.

Description of drawings: come the technical solution of the utility model is described further below in conjunction with the drawings and specific embodiments.

Accompanying drawing is a schematic diagram of the present utility model.

Embodiment: with reference to the accompanying drawings, a kind of automatic switching protector of three phase asynchronous motor is characterized in that: mainly be made up of main A.C. contactor QC, time relay JS on the wiring board in the housing, star starting A.C. contactor YC and triangle AC contactor SC; Its physical circuit is that the A of stop button TA one termination three phase mains goes up mutually, and the other end connects starting button QA one end, and starting button QA is in parallel with A.C. contactor QC1; The starting button QA other end joins with the C of power supply after dividing three the tunnel, the one tunnel to meet thermal relay JR, main A.C. contactor QC successively, and thermal relay JR also meets power supply neutral line N through electric bell DL; The second the tunnel meets triangle AC contactor SC1, connects with time relay JS1, star starting A.C. contactor YC to join with a end after time relay JS is in parallel again, and the C of its another termination power joins mutually; Third Road joins with a end after time relay JS2 and A.C. contactor SC2 are in parallel, and its another termination A.C. contactor YC1, A.C. contactor SC join with the C of power supply.The B that connects power supply after described three road ends connect power supply indicator HD, A.C. contactor QC2 series connection and working station indicator LD, A.C. contactor QC3 connect goes up mutually.During use, when pressing starting button QA, the coil of main A.C. contactor QC, time relay JS and star starting A.C. contactor YC is switched on simultaneously, the main contact closure of QC and YC, and the winding of motor is star connection and begins starting.Through the time-delay of several seconds, the starting current of motor just falls back to a metastable numerical value, and the time-delay normally-closed contact JS1 of time relay JS disconnects, the YC coil blackout, and its main contact disconnects; Simultaneously, the time-delay normally opened contact JS2 closure of JS, the coil of connection triangle AC contactor SC, its main contact closure, motor just enters the triangle running status, and its starting process finishes.

When electromotor overload, thermal relay JR normally-closed contact disconnects, and the coil blackout of main A.C. contactor cuts off motor power, and motor is out of service, thereby has played overload protective function.The thermal relay normally opened contact is connected ring coil simultaneously, reminds operating personnel's handling failure.

During shutdown, only need press stop button TA, motor is just out of service.

Claims

1. an automatic switching protector of three phase asynchronous motor is characterized in that: mainly be made up of main A.C. contactor QC, time relay JS on the wiring board in the housing, star starting A.C. contactor YC and triangle AC contactor SC; Its physical circuit is that the A of stop button TA one termination three phase mains goes up mutually, and the other end connects starting button QA one end, and starting button QA is in parallel with A.C. contactor QC1; The starting button QA other end joins with the C of power supply after dividing three the tunnel, the one tunnel to meet thermal relay JR, main A.C. contactor QC successively, and thermal relay JR also meets power supply neutral line N through electric bell DL; The second the tunnel meets triangle AC contactor SC1, connects with time relay JS1, star starting A.C. contactor YC to join with a end after time relay JS is in parallel again, and the C of its another termination power joins mutually; Third Road joins with a end after time relay JS2 and A.C. contactor SC2 are in parallel, and its another termination A.C. contactor YC1, A.C. contactor SC join with the C of power supply.

2. by the described a kind of automatic switching protector of three phase asynchronous motor of claim 1, it is characterized in that the B that connects power supply after described three road ends connect power supply indicator HD, A.C. contactor QC2 series connection and working station indicator LD, A.C. contactor QC3 connect goes up mutually.