CN1328372A

CN1328372A - Cable fixed zero-power miniaturized over-current relay

Info

Publication number: CN1328372A
Application number: CN 00110503
Authority: CN
Inventors: 乔强
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-06-09
Filing date: 2000-06-09
Publication date: 2001-12-26
Anticipated expiration: 2020-06-09
Also published as: CN100356649C

Abstract

A cable fixed zero-power miniature over-current relay as the over-current protector of AC motor and low-voltage distribution system is composed of casing with fixing ring and screw, drive relay, delay capacitor, rectifier bridge, current sensor and LED. Its advantages include small size, no electric consumption, high sensitivity, multiple functions and long service life.

Description

Cable fixed zero-power miniaturized over-current relay

The present invention relates to a kind of alternating current motor and low-voltage distribution system overcurrent protective device.

Present existing electron type motor protector volume is little, in light weight, power consumption is few, function is many, but the circuit structure complexity, poor reliability, the life-span is short, is subjected to the influence of variations in temperature and voltage fluctuation big; Mechanical simple in structure, reliability height, life-span are long, are not subjected to the influence of temperature and change in voltage, shortcoming is that volume is big, power consumption is big, function is few: all dress is solid on the chassis, be used in combination with the current transformer coupling, wiring is loaded down with trivial details, complexity is heavy, accounts for shortcomings such as the tool size is big.

The objective of the invention is to design on a kind of cable and adorn admittedly, obtain the cable fixed zero-power miniaturized over-current relay of energy as the circuit supply power supply by electromagnetic induction.The advantage that the volume of its existing electron type is little, in light weight, function is many, have again mechanical simple in structure, the reliability height, the life-span is long, anti-dashing shaken the strong point that not influenced by temperature and change in voltage, and not consuming electric power, Current Transformer is not mated, simplified structure, and attaching is convenient.

The object of the present invention is achieved like this: it comprises housing 2, retainer ring 3 is arranged on housing, trip bolt 4 is arranged on the retainer ring, we establish in housing and drive relay 8, drive relay winding two ends and connect delay capacitor 7 and be combined into after the AC relay with the winding of current sensor 1 with rectifier bridge 5 again and connect, the break contact that drives relay is made output interface.

For the ease of monitoring the operating state of this device, on housing 2, establish Light-Emitting Diode 6, light-emitting diode is attempted by and drives the operation demonstration that motor is made at relay 8 winding two ends.

The electricity principle is as follows: after will driving relay K V1 and rectifier bridge QSZ1 being combined into AC relay again with the winding of current sensor T1 mutually and connect the overload and open-phase protection of (with the L1 phase fuse FU1 phase failure, A.C. contactor KM discharges the mode of connection) composition motor; The delay capacitor C1 that is attempted by driving relay K V1 winding two ends does the starting time-delay of motor.

On using method; this cable fixed zero-power miniaturized over-current relay can use separately; also can insert the overcurrent relay of two same structure same specifications respectively; form 2 of motor redundancy structure * overload and 2 * open phase protection, the break contact KV1b, the KV2b that drive relay K V1, KV2 compose in series interface circuit.

Advantage of the present invention is: dress is solid on the cable does not account for size, not consuming electric power, and Current Transformer is not mated; Little, simple in structure, the reliable sensitivity of volume, function is many, the life-span is long, be not subjected to the influence of variations in temperature and voltage fluctuation; Simplified structure, attaching conveniently reduce fault, reduce cost, and long-time running need not be safeguarded.

Accompanying drawing 1 is a structural representation of the present invention;

Accompanying drawing 2 is electrical schematic diagrams of the present invention.

In conjunction with the accompanying drawings structure of the present invention, electric principle, using method and the course of work are further described again below:

It comprises housing 2, retainer ring 3 is arranged on housing, trip bolt 4 is arranged on the retainer ring, in housing, establish and drive relay 8, drive relay winding two ends and connect delay capacitor 7 and be combined into after the AC relay with the winding of current sensor 1 with rectifier bridge 5 again and connect, the break contact that drives relay is made output interface; Establish light-emitting diode 6 on housing 2, light-emitting diode is attempted by and drives the operation demonstration that motor is made at relay 8 winding two ends.

Establish light-emitting diode 6 on housing 2, light-emitting diode is attempted by driving relay 8 winding two ends and does motor operation demonstration.

On using method; this cable fixed zero-power miniaturized over-current relay (to call simple overcurrent relay in the following text) can use separately; also can insert the overcurrent relay of two same structure same specifications respectively and form 2 of motor redundancy structure * overload and 2 * open phase protection, the break contact KV1b, the KV2b that drive relay K V1, KV2 compose in series interface circuit.

The course of work: one, the starting of motor: press starting button SB2, control circuit is by stop button SB1, through starting button SB2, A.C. contactor KM, the break contact KV1b, the KV2b that drive relay K V1, KV2 constitute the closed-loop path, A.C. contactor KM adhesive, its main contact KM1, KM2, KM3 move and close, three-phase alternating current is applied on the winding of motor～3M the motor starting operation by fuse FU1, FU2, FU3 through main contact KM1, KM2, KM3 (L1 passes current sensor T1, L3 mutually and passes current sensor T2 mutually).Meanwhile, the attached power-assist of A.C. contactor closes that contact KM4 is also moving to be closed.After starting button SB2 returned, control loop was by stop button SB1, and the attached power-assist of A.C. contactor closes contact KM4, A.C. contactor KM winding, and break contact KV1b, the KV2b that drives relay K V1, KV2 continues to constitute the closed-loop path, the motor operation.The current sensor T1 that penetrates the L1 phase this moment produces induced voltage and after rectifier bridge QSZ1 conversion delay capacitor C1 is charged, because the capacity of delay capacitor C1 is very big, cause motor in the starting overall process, delay capacitor C1 two ends charging voltage is all the time less than the pick-up voltage that drives relay K V1, make driving relay K V1 be in release condition, its break contact KV1b closure, thereby escape the starting current of motor, guarantee that motor normally moves, overcurrent relay enters operating state, and LED 1 shows and carries out Stateful Inspection.The overcurrent relay structure of passing L3 phase current transducer T2 is identical with L1 phase overcurrent relay with the course of work, and motor starting finishes.

Two; operation troubles protection: when motor emerged in operation overload; overvoltage; under-voltage; stall; short circuit and L2; the phase failure of L3 phase; during open-phase fault; the L1 phase line current of passing current sensor T1 rises and produces induced voltage at its winding two ends when driving the pickup value of relay K V1; drive relay K V1 adhesive; its break contact KV1b disconnects; A.C. contactor KM discharges (the L1 phase fuse FU1 phase failure; A.C. contactor KM discharges); its main contact KM1; KM2; KM3 cuts off three-phase alternating-current supply; motor～3M is out of service, thereby realizes the overload and open-phase protection of motor operation.Insert the overcurrent relay of two-phase (L3 phase current transducer T2) isostructure same specification respectively and can form 2 of redundancy structure * overload and 2 * open phase protection.

Three; starting failure protection: when motor transships in starting process; stall and L2; the phase failure of L3 phase; during open-phase fault; the L1 phase line current of passing current sensor T1 rises and produces induced voltage at its winding two ends and delays time through delay capacitor C1 charging; induced voltage is to the pickup value that drives relay K V1 and adhesive after several seconds; its break contact KV1b disconnects; A.C. contactor KM discharges (the L1 phase fuse FU1 phase failure; A.C. contactor KM discharges); its main contact KM1; KM2; KM3 cuts off three-phase alternating-current supply; motor～3M is out of service, realizes the overload and open-phase protection of motor starting.Insert the overcurrent relay of two-phase (L3 phase current transducer T2) isostructure same specification respectively and can form 2 of redundancy structure * overload and 2 * open phase protection.

Four, overcurrent protection: when power consumption equipment emerged in operation overloads such as the single-phase motor of low-voltage distribution system, spot welding machine, transformer or short trouble cause electric current to increase rapidly; the current sensor T electric current that passes overcurrent relay in service produces induced voltage at its winding two ends; make and drive relay K V adhesive; interface output KVb disconnects the electromagnetic switch winding; electromagnetic switch discharges also cuts off circuit, power consumption equipment is protected or output signal is made the usefulness of control and detection.

Claims

1, cable fixed zero-power miniaturized over-current relay; Comprise housing [2], retainer ring [3] is arranged on housing, trip bolt [4] is arranged on the retainer ring, it is characterized in that establishing in the housing driving relay [8], drive relay winding two ends and connect the same rectifier bridge of delay capacitor [7] [5] and be combined into after the AC relay with the winding of current sensor [1] again and connect, the break contact that drives relay is made output interface.

2, according to the said cable fixed zero-power miniaturized over-current relay of claim 1, it is characterized in that on housing [2], establishing light-emitting diode [6], light-emitting diode is attempted by the two ends that drive relay [8] winding.

3, according to claim 1 or 2 said cable fixed zero-power miniaturized over-current relays; feature on using method is to use separately; also can insert the overcurrent relay of two same structure same specifications respectively; form 2 of motor redundancy structure * overload and 2 * open phase protection, the break contact KV1b, the KV2b that drive relay K V1, KV2 compose in series interface circuit.