CN2258326Y

CN2258326Y - Phase interruption and overload protection for three-phase motor

Info

Publication number: CN2258326Y
Application number: CN 96243986
Authority: CN
Inventors: 张国卿; 高国欣; 张乐平; 张松建
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-10-21
Filing date: 1996-10-21
Publication date: 1997-07-23
Anticipated expiration: 2006-10-21

Abstract

The utility model relates to a phase interruption and overload protective device for a three-phase motor, which comprises a group of phase interruption and overload protectors, each of which is composed of manual switches K1, K2, an alternating current contactor J1 and the contact Jt1 of a thermal relay Jt. The utility model is provided with an alternating current contactor J2 in a loop of each of the protectors. The normally open contacts of the alternating current contactors J2 and the normally open contacts of the alternating current contactor J1 are connected in series. One phase of the working power supply of each of the alternating current contactors J2 is shared with each of the alternating current contactors J1, and the other phase is not used by each of the alternating current contactors J1. The device can effectively carry out control of complete phase and prevent the phase interruption of any phase of three-phase power supply from damaging a motor. The utility model can be widely applied to production industries which take a three-phase motor as dynamic force.

Description

The threephase motor phase failure, overload protection arrangement

The utility model discloses a kind of threephase motor phase failure, overload protection arrangement, belong to the electric prospection technical field.Especially be suitable for the phase failure, the overload protection of threephase motor.

The existing threephase motor phase failure, overload protective device kind are a lot, but the working power of these existing threephase motor protectors all is the wherein two-phases in the three-phase power line, when any phase phase failure in this two-phase, the protector action, cut off the electricity supply, avoid motor to scrap because of phase failure work; Yet, if the phase failure is not the two-phase power supply that protector work is used, but an other phase power supply that disconnects; then protector is failure to actuate, and at this moment protector does not have the open phase protection effect, motor two-phase power supply work this moment; still scrap motor, cause unnecessary loss.

The purpose of this utility model provides a kind of threephase motor phase failure, overload protection arrangement, and this protective device is installed in threephase motor and the foreign minister's electric power loop, can control each phase line of foreign minister's power supply well.When what of foreign minister's power supply one when breaking mutually, the utility model cuts off being connected of threephase motor and foreign minister's power supply immediately, and threephase motor is worked under phase failure situation, stops threephase motor and scraps because of phase failure work.

Taked following technical scheme for realizing the purpose of this utility model:

Make a threephase motor phase failure, overload protection arrangement; this protective device contains an existing motor phase failure, overload protective device; in the control loop of existing motor protector, dispose an A.C. contactor again, make the threephase motor phase failure, overload protection arrangement.The control end of the A.C. contactor of configuration and the control end of existing protector polyphone; The working power of A.C. contactor, one end and existing protector working power shared mutually, the other end is an other phase of three-phase power line.

Further describe technical characterictic of the present utility model below in conjunction with accompanying drawing:

Accompanying drawing, the electric theory structure schematic diagram of an embodiment who preferentially selects for use for the utility model.

As shown in drawings, the B phase of one termination three phase mains of the normally-closed contact of the hand switch K1 among the figure, one end of the normally opened contact of other end serial connection hand switch K2, one end of the actuating coil of the other end serial connection A.C. contactor J1 of K2, the normally-closed contact Jt-1 of thermal relay Jt is serially connected between A.C. contactor J1 actuating coil and the power supply C; Three normally opened contact J1-2 of A.C. contactor J1 control three phase mains and threephase motor, have constituted the existing phase failure, overload protective device.When A, B, C three phase mains normal power supply, press hand switch K2, B phase power supply is through manual K switch 1, K ₂, A.C. contactor J1 actuating coil, normally-closed contact Jt1 to the C phase power supply of thermal relay Jt constitutes the loop, A.C. contactor J1 adhesive, its normally opened contact group J1-2 closure, energized line and threephase motor make motor operation work; The contact of the normally opened contact J1-2 of A.C. contactor J1 is attempted by hand switch K2 two ends simultaneously, goes into the self-closing loop, and protector enters normal operating conditions.If during overload (thermal relay Jt is connected in the motor, herein omission), thermal relay Jt action, its normally-closed contact Jt1 disconnects, and cuts off the working power loop of A.C. contactor J1, and then A.C. contactor J1 jumps and breaks, and cuts off the power supply of motor; As B mutually or during any phase phase failure of C phase power supply, all cut off the working power of A.C. contactor J1, make A.C. contactor J1 be returned to and stop disconnected state, cut off the three-phase central battery supply of threephase motor, avoid the threephase motor open-phase running to damage motor.But this protector is when the A phase phase failure as shown in the figure, and A.C. contactor J1 does not jump disconnected, and protector does not have protective effect, still damages motor.Three the normally opened contact J2-2 of the A.C. contactor J2 of the utility model configuration and the normally opened contact J1-2 of A.C. contactor J1 contact; The working power of A.C. contactor J2 and the shared C of A.C. contactor J1 be (also can shared B phase) mutually, and its another phase power supply is an A phase power supply.Like this when A phase, the phase failure of C phase power line, exchange contact J2 and jump disconnectedly because of the power supply of losing the job, the normally opened contact J2-2 disconnection of A.C. contactor J2 has disconnected threephase motor and power line, has stopped to damage motor because of the phase failure of A phase.Reach the full phase phase failure control of three phase mains, realized the purpose of this utility model.

The utility model has following advantage:

1, simple in structure, make transaction, cost is low, is convenient to promote;

2, control mutually entirely is reliable, stops the phenomenon generation that the phase failure damages motor effectively.

The used components and parts of the utility model all are existing components and parts on the market.The utility model is installed together by the accompanying drawing line, makes the threephase motor phase failure, overload protection arrangement.A in the accompanying drawing, B, C end join with the power line outside line, and A ' B ' C ' connects threephase motor.

Claims

1. the threephase motor phase failure, overload protection arrangement, it contain one group of B phase C that is serially connected in three-phase power line mutually between, the phase failure that is connected to form by the normally-closed contact Jt1 of hand switch K1, K2, A.C. contactor J1, thermal relay Jt, overload protective device, it is characterized in that: the described phase failure, overload protection arrangement are to have disposed A.C. contactor J2 in former protector loop, working power one end of A.C. contactor J2 joins with A, and the other end is connected in any phase of A.C. contactor J1 working power; The normally opened contact J2-2 of A.C. contactor J2 and the normally opened contact J1-2 of A.C. contactor J1 polyphone are made the phase failure, overload protection arrangement.