CN2567759Y

CN2567759Y - Contactless open-phase protection A.C. contactor

Info

Publication number: CN2567759Y
Application number: CN 01264558
Authority: CN
Inventors: 陈菁菁
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-09-03
Filing date: 2001-09-03
Publication date: 2003-08-20
Anticipated expiration: 2011-09-03

Abstract

The utility model relates to a contactless novel phase-absent protector of an alternating current contactor. A control element of the utility model is a bidirectional thyristor which is controlled by a triggering circuit of the bidirectional thyristor; the bidirectional thyristor is turned on or off to control a motor and other electric equipment to work. An anode of the bidirectional thyristor is connected with a power source and a cathode of the bidirectional thyristor is connected with the motor and the other electric equipment. According to the alternating current contactor which connected with the device, the phenomena of abrasion and clamping, the ignition of contact points and the burnout of coils can not happen.

Description

Contactless novel open phase protection A.C. contactor

The utility model relates to a kind of device of protection switch circuit.Refer more particularly to the protective circuit device of threephase motor.

At present, in China numerous peasants and herdsmen area, especially in the small processing factory and the private enterprise in the rural area, A.C. contactor plays important effect for state-owned enterprise, township enterprise.But existing A.C. contactor contact contact and magnet exciting coil burn phenomenon and take place often.So not only cause loss economically, but also influence is produced.

The main cause analysis that A.C. contactor burns:

What we knew that present A.C. contactor adopts is the electromagnetic start principle, utilizes coil to produce electromagnetic force exactly armature is picked up, and armature drives contact movable contact and contact break closure, and electric current passes through contact after the closure to power devices.In the process of contact conversion, contact break and movable contact will produce very big electric spark, burn contact contact and magnet exciting coil often, influence normal power supply.This is to cause the A.C. contactor cause faults.

The purpose of this utility model is: design a kind of simple in structurely, easy to operate, be swift in motion, do not have machinery mill card, the A.C. contactor that has the open phase protection effect that no coil and contact burn.

The utility model is achieved in that its employing bidirectional triode thyristor replaces the contact contact, and thyristor gating circuit has replaced the mechanical action of magnet exciting coil.Utilize the conducting of bidirectional triode thyristor and close the work of controlling motor and some power consumption equipments.Such A.C. contactor does not have machinery mill card, does not have the phenomenon of burning of contact contact and magnet exciting coil, has prolonged the useful life of contactor.

Second characteristic of the present utility model: be that phase failure protection function is arranged; it adopts electric capacity neutral point equilibrium principle; as long as an outage is mutually arranged in the three phase mains in the work, this A.C. contactor can be at 0.2 second internal cutting off power supply, the safety of protection motor and all power consumption equipments.And circuit theory is simple, and general electrician can both accept.

Below in conjunction with accompanying drawing implementation example of the present utility model is described in detail:

Fig. 1 is bidirectional triode thyristor A.C. contactor circuit theory diagrams

Bidirectional triode thyristor directly connects power consumption equipment.The conducting of bidirectional triode thyristor with by controlling by circuits for triggering, form owing to the conducting of bidirectional triode thyristor and by changing, therefore, do not have machinery to grind and block by its internal physical, loss of contact contact and contact spark phenomenon, thereby the useful life of having improved A.C. contactor.

Fig. 2 is a structure connection diagram of the present utility model

The anode of bidirectional triode thyristor connects three phase mains, and negative electrode connects motor or other power consumption equipments, and trigger electrode connects the trigger electrode control circuit.Open-phase protection circuit is connected on the silicon controlled anode.

Fig. 3 is the open-phase protection circuit that adopts electric capacity neutral point equilibrium principle to make.Under the normal condition (when three-phase electricity all has electricity), the electric current and voltage at neutral point E place all is zero, and no current passes through on the BHJ relay, and the BHJ relay is not inhaled.When lacking one in the three phase mains mutually during electricity, the voltage at neutral point E place is just non-vanishing, and the BHJ relay energized cuts off bidirectional triode thyristor trigger electrode circuit, and bidirectional triode thyristor ends, and stops to power devices, plays and protects the power consumption equipment purpose of safety.

Claims

1. contactless novel open phase protection A.C. contactor is characterized in that: its adopts bidirectional triode thyristor and the thyristor gating circuit main element as A.C. contactor.Utilize the conducting of bidirectional triode thyristor and close the work of controlling motor and other power consumption equipments.

2. A.C. contactor according to claim 1 is characterized in that: described protection circuit is a bidirectional triode thyristor.