CN100356649C

CN100356649C - Cable fixed zero-power miniaturized over-current relay

Info

Publication number: CN100356649C
Application number: CNB001105035A
Authority: CN
Inventors: 乔强
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-06-09
Filing date: 2000-06-09
Publication date: 2007-12-19
Anticipated expiration: 2020-06-09
Also published as: CN1328372A

Abstract

The present invention discloses a cable fixed zero-power miniaturized over-current relay which relates to an over-current protection device for an AC motor and a low-voltage distribution system. The present invention comprises a casing, wherein a fixing ring is arranged on the casing; fastening screws are arranged on the fixing ring; a driving relay, a time delay capacitor, a rectification bridge and a current sensor are arranged in the casing; light emitting diodes for a motor to operate and display are also arranged on the casing. Fixation on cables has the advantages of no size occupation, no electric energy consumption and no current mutual inductor for matching; the present invention has the advantages of small size, simple structure, convenient assembly, reliability, sensitivity, more functions and long service life; the present invention is not influenced by temperature change and voltage pulsation; the present invention is not maintained when running for long time.

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, the reliability height, the life-span is long, is not subjected to the influence of temperature and change in voltage, and shortcoming is that volume is big, power consumption is big, function is few; All dress is solid on the chassis, is used in combination with the current transformer coupling, and wiring is loaded down with trivial details, and is complicated heavy, occupies shortcomings such as size is big.

The objective of the invention is to design and adorn admittedly on a kind of cable, 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 variations in temperature and voltage fluctuation, 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: cable fixed zero-power miniaturized over-current relay comprises housing 2, retainer ring 3 is arranged on housing, trip bolt 4 is arranged on the retainer ring, it is characterized in that driving relay K V1 winding two ends and the rectifier bridge QSZ1 dc terminal in the housing and connect be combined into AC relay after, delay capacitor C1 again with drive relay K V1 winding two ends and connect, the interchange end of AC relay is the winding of rectifier bridge QSZ1 interchange end and current sensor T1 and connects that the break contact KV1b that drives relay K V1 makes output interface.

For ease of monitoring the operating state of this device, on housing 2, establish Light-Emitting Diode LED1, light-emitting diode is attempted by and drives the operation demonstration that motor is made at relay K V1 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, and little, simple in structure, the reliable sensitivity of volume, function is many, temperature rise is low, the life-span is long, be not subjected to the influence of variations in temperature and voltage fluctuation; Simplified structure, attaching is convenient, reduces fault, reduces cost, and long-time running need not be safeguarded.

Accompanying drawing 1 is a structural representation of the present invention, among the figure: 1, current sensor, 2, housing, 3, retainer ring, 4, trip bolt, 5, rectifier bridge, 6, Light-Emitting Diode, 7, delay capacitor, 8, drive relay.

Accompanying drawing 2 is electrical schematic diagrams of the present invention, among the figure: T1 current sensor, QSZ1 rectifier bridge, the C1 delay capacitor, KV1 drives relay, LED1 Light-Emitting Diode, KV1b, KV2b drive the relay break contact, the SB1 stop button, SB2 starting button, KM A.C. contactor, FU1, FU2, FU3 fuse, KM1, KM2, KM3 A.C. contactor main contact, the attached power-assist of KM4 A.C. contactor closes contact ,～3M motor.

In conjunction with the accompanying drawings structure of the present invention, electric principle, using method and the course of work are being further described 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 K V1, drive relay winding two ends and meet delay capacitor C1, be combined into after the AC relay with the winding of current sensor T1 again and connect with rectifier bridge QSZ1, the break contact KV1b that drives relay makes output interface; Establish LED 1 on housing 2, light-emitting diode is attempted by and drives the operation demonstration that motor is made at relay K V1 winding two ends.

Establish LED 1 on housing 2, light-emitting diode is attempted by driving relay K V1 winding two ends and does motor operation demonstration.

On using method; this cable fixed zero-power miniaturized over-current relay (hereinafter to be referred as overcurrent relay) 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 passes current sensor T2 mutually) 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; driving relay 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 passes current sensor T2 mutually) 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 driving relay (KV1) winding two ends and rectifier bridge (QSZ1) dc terminal in the housing and connect be combined into AC relay after, delay capacitor (C1) again with drive relay (KV1) winding two ends and connect, the interchange end of AC relay is the winding of rectifier bridge (QSZ1) interchange end and current sensor (T1) and connects that the break contact (KV1b) that drives relay (KV1) is made output interface.