CN2121092U

CN2121092U - Three-phase ac. contacting apparatus with open-phase protect

Info

Publication number: CN2121092U
Application number: CN 92202212
Authority: CN
Inventors: 粟多见
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-01-31
Filing date: 1992-01-31
Publication date: 1992-11-04

Abstract

The utility model provides a three-phase AC contactor with phase interruption protection, which comprises an existing AC contactor and a phase interruption protective device. The phase interruption protective device is arranged below the basal seat of the existing AC contactor to form an integral structure, and one side of the lower part of the basal seat is provided with an earth wire terminal. One end of three star-shaped sampling capacitors is respectively connected with the three screws of the fixed contact of the lead wire end of the existing AC contactor, the other end of the three star-shaped sampling capacitors is connected into an asterism, and one group of normally closed contacts of an executive breaker is connected in series with the coils of the existing AC contactor. When the utility model is used, as the usage of an ordinary AC contactor, and only an earth wire is additionally connected to achieve the phase interruption protection of a controlled motor.

Description

Three-phase ac. contacting apparatus with open-phase protect

The utility model provides a kind of A.C. contactor that can make open phase protection when the three phase mains phase failure to threephase motor, is a kind of three-phase ac contactor with open phase protection.Existing A.C. contactor is not have phase failure protection function.

Open phase protection has various schemes, and many open phase protection products are also arranged, but mostly needs to cooperate three-phase ac contactor to use, and installs, and complexity is adjusted in wiring, makes troubles to use, is difficult for promoting.

The purpose of this utility model designs for the problem that solves phase failure protector and A.C. contactor and be integrated.It can make former various three-phase ac contactor all be with phase failure protection function, can form the three-phase ac contactor that series has open phase protection, and needs any adjustment when using, and can keep the characteristics and the using method of former A.C. contactor simultaneously again.Only need ground wire neutral line of adjunction when using this A.C. contactor, just can make open phase protection the threephase motor of being controlled.Remove ground wire and just revert to common A.C. contactor.

The purpose of this utility model is finished as follows: install open phase protection additional below existing three-phase ac contactor.The principle of this open phase protection be the principle of utility model patent " phase failure protector " according to my invention design (patent No.: 91203232.4) it mainly comprises star sampling capacitor device, rectifier, the filtering delay-time capacitor is carried out relay etc.The course of work with three-phase ac contactor of open phase protection: when motor runs well; the execution relay is failure to actuate; when a disconnected phase or two phase times of three phase mains; carrying out relay works immediately; make ac contactor coil lose pick-up voltage; the master control contact disconnects, thereby cuts off the whole power supplys that enter motor, has avoided single-phase motor running and burns out.Because A.C. contactor starts frequent, it is disconnected the contact damage often to occur, causes the phase failure that motor is damaged, and when this fault takes place, carries out relay and also works the protection motor of cutting off the electricity supply.In addition, if under the situation of the phase failure actuating motor, this A.C. contactor can not adhesive, power supply also just can not enter motor, thereby has also protected motor.Be described in detail below in conjunction with accompanying drawing:

One, introduce accompanying drawing: this accompanying drawing is preferred embodiment of the utility model figure.

Accompanying drawing 1 is the use schematic diagram with three-phase ac contactor of open phase protection.

Accompanying drawing 2 is the structural representation with three-phase ac contactor of open phase protection.

Accompanying drawing 3 is the circuit theory diagrams with three-phase ac contactor of open phase protection.

Accompanying drawing 4 is the circuit theory diagrams with three-phase ac contactor of open phase protection and phase failure indication.

Wherein, have in the use schematic diagram of three-phase ac contactor of open phase protection at accompanying drawing 1; (a) be picture in kind; its top is former A.C. contactor main body; the bottom is the open phase protection part; among the figure; (A1), (B1), (C1) are the A.C. contactor input terminal; (A2), (B2), (C2) are outlet terminal; promptly connect the terminal of motor, (CJ1), (CJ2) be two binding posts of coil of A.C. contactor, (JC) is one group of normally opened contact of A.C. contactor; being self holding contact, (DO) is the binding post of the neutral line for ground wire.(b) for using winding diagram, (A), (B), (C) are three-phase alternating-current supply, (K) be Three-phase knife switch, (RDA), (RDB), (RDC) are fuse, (AN1), (AN2) is the start and stop button, (JK) for carrying out the normally-closed contact of relay, (CJ) be ac contactor coil, (CJA), (CJB), (CJC) are the master control contact of A.C. contactor, (D) be three-phase alternating-current motor, need only during use and press winding diagram and the corresponding connection of picture binding post in kind.When if the coil voltage of A.C. contactor is 220 volts, then " * " among the figure located to disconnect, can just connect as dotted line.

Have in the structural representation of three-phase ac contactor of open phase protection at accompanying drawing 2; (1) is the A.C. contactor upper case; (2) be this A.C. contactor open phase protection part base shell; (3) be open phase protection part printed circuit board (PCB); it is fixed on the base plate of former A.C. contactor; (4) be the screw rod of fixing printing plate and base shell; (5) be arc-extinguish chamber; (6) be moving contact; (7) be fixed contact; (8) be the screw of fixing fixed contact and outlet terminal; (9) for diameter be three apertures of one millimeter near (8) and outer casing inner wall; (10) be former A.C. contactor base plate; (11) be three identical apertures of corresponding (9); (12) be the wiring points of three oil capacitors on printed panel; go up and pass the aperture of (11) and (9) during assembling respectively from this some connection with three leads; be pressed on then on three screws of (8); make its UNICOM; (13) for ground wire be the binding post of the neutral line; (14) be two leads carrying out the normally-closed contact of relay; it is passed base plate (10); then from the binding post weldering down with ac contactor coil one end; lead is with on ac contactor coil connects, and another root lead is connected on the binding post of ac contactor coil of disconnection.

Have in the circuit theory diagrams of open phase protection three-phase ac contactor at accompanying drawing 3; (C1); (C2); (C3) be star sampling capacitor device; (C4) be the filtering delay-time capacitor; (ZL) be the rectifier bridge heap; (J) for carrying out relay; (JK) be the normally-closed contact of (J); (CJA); (CJB); (CJC) be three pairs of master control contacts of three-phase ac contactor; (CJ) be ac contactor coil; (JC) be the self holding contact of A.C. contactor; (AN1); (AN2) for starting, stop button, K are Three-phase knife switch; (RDA); (RDB); (RDC) be fuse; (A); (B); (C) be three phase mains,, (D) be three-phase alternating-current motor (DX) for ground wire is the neutral line.

In this figure, (C1), (C2), (C3) adopt the withstand voltage 400 volts oil capacitor of low capacity, and capacity requirement equates, (ZL) is that (1A/100V) bridge is piled, (J) be (24) volt small-sized DC relay, its contact current capacity is decided on the ac contactor coil electric current.

At accompanying drawing 4(a) have in the three-phase ac contactor circuit theory diagrams of open phase protection and phase failure indication, except that (RA), (RB), (RC) for dropping resistor and (NA), (NB), (NC) be the neon tube, all identical with Fig. 3, (b) be the assembling schematic diagram of phase failure indication on arc-extinguish chamber, (R) be three dropping resistors, N is three neon tubes, (R), (N) is after series connection on the little printed panel, pass the hole on the arc-extinguish chamber, be connected on the copper sheet of arc extinguishing flaring, this copper sheet is stuck on the arc-extinguish chamber edge, totally six up and down; After arc-extinguish chamber was fixing, six copper sheets should be pressed on the copper coin of turnover line terminals correspondence, made it guarantee good contact.

Two, following detailed introduction has the course of work of the three-phase ac contactor of open phase protection:

At first; the three-phase ac contactor that will have open phase protection connects as figure (1); knife switch (K) then closes; press start button (AN1), motor (D) just runs well, at this moment; since (C1), (C2), (C3) for etc. the star circuit of capacity; make between (O) point and the ground wire no-voltage or voltage very little, can not make after the rectification and carry out relay (J) action, motor just runs well always.

1) makes (A) phase or (B) phase or (C) the phase phase failure for a certain reason; the perhaps arbitrarily two-phase phase failure simultaneously, at this moment, corresponding (C1) or (C2) or (C3) two ends no-voltage; make the star circuit disequilibrium; (O) and just have tens volts voltage to produce between the ground wire, make (J) action after the rectification, normally-closed contact (JK) disconnects; make the ac contactor coil outage; master control contact (CJA), (CJB), (CJC) just disconnect, and motor has been protected in motor (D) stall.

2) because A.C. contactor starts frequently, its contact is decreased disconnected easily, also can cause the phase failure; damage motor, when this kind fault takes place, broken as (CJB) contact; at this moment; capacitor (C2) two ends no-voltage makes star sample circuit disequilibrium, makes between (O) point and the ground wire and produces tens volts of voltages; carry out relay (J) action; normally-closed contact (JK) disconnects, and A.C. contactor master control contact also disconnects thereupon, thereby has protected motor.

3) under the situation of the phase failure, disconnected as (RDC), actuating motor; at this moment because (C1) two ends no-voltage, existing tens volts voltages (O) and between the ground wire have made the normally-closed contact disconnection of execution relay; therefore can't actuating motor, thus motor also protected.

Three, the course of work that has the three-phase ac contactor of the open phase protection and phase failure indication:

From accompanying drawing 4 as can be seen, when motor ran well, because master control contact (CJA), (CJB), (CJC) of A.C. contactor are closed, at this moment neon tube (NA), (NB), the equal no-voltage in (NC) two ends were not luminous.When a certain disconnected mutually as (C); because the effect of open phase protection; A.C. contactor master control contact just can disconnect; the motor stall; at this moment neon tube (NC) is not luminous; and neon tube (NA), (NB) by (RA), (RB) step-down through (C2), (C3), (O) and (ZL) composition loop makes neon tube (NA), (NB) luminous.The maintenance personal knows that phase of having broken mutually at a glance.Two-phase phase failure principle is also identical arbitrarily, and all the other operation principles are identical with Fig. 3, here no longer narration.

Characteristics of the present utility model: because the open-phase protection part is not affected by watt level, do not adjust, therefore can consist of the three-phase ac contactor that series has open-phase protection; When using this A.C. contactor or changing the A.C. contactor of original all size, only need ground wire of adjunction to carry out open-phase protection to motor, do not account in addition the installation site, if ground wire is taken down and can recover the performance of former A.C. contactor, thereby promote, extremely easy to use; Because open-phase protection partly adopts durable oil capacitor, and behind continuous phase time and the execution open-phase protection, the open-phase protection part all is in off position, thereby the life-span is long; Element is few, and cost is low, is convenient to produce.

Claims

1, a kind of three-phase ac contactor with open phase protection; it is to be made of existing A.C. contactor and open phase protection two parts; it is characterized in that: open phase protection partly is contained in and forms an integral body below the existing A.C. contactor base, and a following side has an earth connection terminal.

2, the A.C. contactor with open phase protection according to claim 1 is characterized in that the star electric capacity (C by the capacity of grade ₁), (C ₂), (C ₃), bridge heap (ZL), filtering delay-time capacitor (C ₄), carry out relay (J) and constitute (C ₁), (C ₂), (C ₃) an end be connected on three screws of fixedly fixed contact of A.C. contactor leading-out terminal, the other end connects together and is asterism, the normally-closed contact (JK) of carrying out relay is serially connected with in the coil of A.C. contactor.

3, according to the A.C. contactor with open phase protection and phase failure indication of the described formation of claim 1, it is characterized in that by dropping resistor (R _A), (R _B), (R _C) and neon bulb (N _A), (N _B), (N _C) constitute, be installed in above the A.C. contactor arc-extinguish chamber after dropping resistor and the neon bulb series connection, the aperture that passes on the arc-extinguish chamber with lead is connected on six copper sheets that are stuck in the arc-extinguish chamber edge respectively, these six copper sheet correspondences are stuck on the position of six fixed contact copper coins of turnover line of A.C. contactor, after arc-extinguish chamber is fixing, copper sheet and copper coin are connected.