CN2267565Y - Energy-saving type electrical leakage protector - Google Patents

Abstract

The utility model belongs to a protector for a low-voltage electrical apparatus, mainly comprising a detection circuit, an adjusting circuit of amplification enlarge and sensitivity and a trigger drive circuit for controlling the action of an executive apparatus. A control and direct-current starting running circuit is arranged; the control of an alternating-current contactor and the direct-current starting running circuit are mainly composed of a two unidirectional controlled silicon SCR1 and SCR2; the control poles of the SCR1 and the SCR2 are connected with the output end of the trigger drive circuit; the SCR1 can carry out half wave rectification for low-voltage of alternating-current; the low-voltage of alternating-current can be applied to a coil of an alternating current contactor; a power supply of alternating-current and 220V after the half wave rectification of the SCR2 can be applied to the coil of an alternating current contactor.

Description

Energy-saving earth leakage protective device

The utility model belongs to the residue leakage current protection device in the low-voltage electrical apparatus category, mainly proposes a kind of energy-saving earth leakage protective device.

Residue residual operating current protective device in using now; it has instrument transformer as the leakage current detecting element; induced signal amplifying circuit, sensitivity adjusting circuit are set, and drive A.C. contactor release outage, and delay circuit and integral form memory circuit are set by electromagnetic type relay.It is bad that its electromagnetic type relay that adopts in back utmost point control very easily causes loose contact to control owing to the easy oxidation of contact; Electromagnetic type relay belongs to the power device in this circuit, certainly lead to electric arc when starting, has more accelerated the rate of decay of contact thus; The operating voltage range of electromagnetic type relay is narrower, crosses low phenomenon owing to overtension often occurs in normal low-voltage power supply side, causes the damage device maybe may cause complete machine malfunctioning.In addition, electronic circuit all adopts the semiconductor discrete device, thereby causes the parameters discreteness in the entire circuit big, influences the entire circuit reliability of operation greatly, and the entire circuit power consumption is big, shortens the useful life of components and parts.

The purpose of this utility model promptly is this, proposes a kind of energy-saving earth leakage protective device, makes it have the premium properties that improves the operation functional reliability and reduce circuit power consumption, and make its reasonability that more becomes on structural circuit and manufacture craft.

The utility model is finished the technical scheme that its foregoing invention task takes: it mainly includes the testing circuit that low-voltage distributing line residue leakage current is detected and exports induced signal, to amplifying circuit, the sensitivity adjusting circuit that induced signal is amplified and regulates, the triggering drive circuit of control performer action; It is characterized in that being provided with mainly by two unidirectional controllable silicon S CR ₁, SCR ₂The control of the A.C. contactor that constitutes and DC start operation circuit, wherein two unidirectional controllable silicon S CR ₁, SCR ₂The control utmost point connects the output that triggers drive circuit, SCR respectively ₁Be added on the A.C. contactor SCR to exchanging the low-voltage halfwave rectifier ₂Alternating current 220V power supply halfwave rectifier is added on the A.C. contactor.

Prime signal amplification circuit of the present utility model adopts LM324 four high guaily unit integrated amplifier.

The utility model adopts 7809 circuit of three-terminal voltage-stabilizing integrated that dc supply is carried out voltage stabilizing and handles.

Outstanding advantage of the present utility model is to have adopted three integrated circuits to replace a large amount of semiconductor discrete devices, improved operational reliability, with the power consumption in the one-way SCR replacement electromagnetic relay reduction entire circuit, save cost, simplified manufacture craft, two one-way SCRs have constituted DC start operation circuit, thereby reach the function of saves energy, silent running, its energy-saving efficiency can reach more than 95% and (cooperate with A.C. contactor) after tested, has good social, economic benefit.

The utility model has adopted advanced integrated circuit technique and thyristor control technology in circuit, make its reasonability that more becomes on structural circuit and manufacture craft.

Accompanying drawing 1 provides embodiment of the present utility model.

Accompanying drawing 1 is the utility model circuit electrical schematic diagram.

In conjunction with the accompanying drawings the utility model structure is further specified: zero sequence current mutual inductor HB, with the low-voltage distributing line of three-phase four-wire system with equidirectional and pass HB, during normal the operation, be exportable induced signal as long as relative residue leakage current HB appears in protected side; Current-limiting resistance R in the ac amplifier circuit ₁And R ₂Constitute attenuator circuit, signal is through C ₁After the filtering by D ₁, D ₂Double limiting is from C ₂Be coupled to amplifier A ₁, A ₁Be negative feedback backward crossover stream amplifier, the signal after the amplification is by C ₄Output is through D ₃, D ₄Rectification input voltage comparator A ₂End of oppisite phase, C ₅R ₇Be inverse time lag circuit, A ₂W on the in-phase end plays the sensitivity regulating action, and regulate W and can give predetermined value, when the signal arrival reaches predetermined value, A ₂(output) is through C ₆Export a negative pulse and remove to trigger IC ₂6 pin, IC ₂5 pin output high potential signal and the 30S that delays time (setting-up time), this signal is through D ₁₄Output forms tripping operation for the first time.

IC ₂(time-delay 1) 5 pin are got back to electronegative potential after crossing 30S, and are passed through C ₁₂Produce a negative pulse and trigger IC ₂8 pin, 9 pin (time-delay 2) make the delay time of output 30S (supposing the time), this delay time is memory time, i.e. A ₂Leakage current signal, IC only appear once remaining ₂Have only 5 pin output signals, A in memory time ₂Output leakage current signal again, IC ₂5 pin, 9 pin promptly be all high potential.

A ₃, A ₄Form memory circuit (positive feedback type), R ₁₆, D ₅D ₆Form NAND gate circuit, IC ₂₅Pin, 9 pin are electronegative potential simultaneously or have only an electronegative potential, D ₇Just export electronegative potential, D ₈(memory circuit output) also is electronegative potential, therefore then can not form memory; If IC ₂5 pin, 9 pin are exported high potential, D so simultaneously ₇Also export high potential, D ₈End produces a memory signal, if power supply constantly this signal be permanent memory signal, if after interrupting memory, then need the back IC that closes again behind the powered-down switch ₂The clear circuit that powers up that 4 pin, 10 pin are formed makes IC ₂5 pin, 9 pin export simultaneously and eliminate memory behind the electronegative potential, entire circuit just can be recovered normal operation.

LED ₂Be tripping operation, indicator light, (during operation) LED went out (it is output as electronegative potential) when entire circuit was closed a floodgate, and bright during tripping operation (it is output as high potential) goes out after the coincidence.If during permanent tripping operation, LED ₂Also be permanent bright.

By BG ₁And BG ₂(NPN type triode) constitutes i.e. 2 the unidirectional controllable silicon S CR of control performer ₁, SCR ₂The triggering drive circuit, turn on the power switch, just often, BG ₁Base stage be electronegative potential, BG ₁Current collection high potential very, line power V+ this moment (hereinafter to be referred as V+) is through R ₂₄Be divided into the two-way high potential after the current limliting, BG ₁End, the one tunnel through R ₂₅The output high potential makes SCR ₁Full conducting, the N on the transformer B ₃Winding is the 10V alternating voltage, and an end is connected on the general supply N line (hypothesis) N so ₃The other end through SCR ₁Halfwave rectifier outputs to return on the power supply N line on the coil of load A.C. contactor C of this machine and constitutes the loop, from SCR ₁The half-wave voltage of output can make A.C. contactor normally move and (but need SCR ₂Start), narrate SCR below ₂Starting process: capacitor C ₁₄Be in discharge condition at ordinary times, turn on the power switch, power supply V+ is through R ₂₄The second road high potential signal makes C after the current limliting ₁₄Be in charged state, make C ₁₄Negative terminal only produce a positive pulse, (as long as the continuous C of power supply ₁₄The C that finishes charges ₁₄Negative terminal be no signal output).This positive pulse signal is through BG ₂Amplify and remove to trigger SCR ₂, general supply A line is through SCR ₂Output to after the rectification on the coil of A.C. contactor C and finish starting.The size of starting current is by C ₁₄Charging interval and determine.

LED when normal operation ₂Bright (the residue leakage current signal promptly occurring) BG ₁On the base stage high potential, full conducting.Power supply V+ is through R ₂₄High potential signal after the current limliting is by BG ₁Conducting ground connection becomes electronegative potential; SCR ₁Control extremely go up do not control voltage and by and drive A.C. contactor and disconnect, C simultaneously ₁₄Pass through BG ₁Discharge process is finished in conducting.

R ₃₃And C ₉The SCR that forms ₁Protective circuit is used for protecting one-way SCR not to be subjected to overvoltage of power supply, to open and close the interference that the load overvoltage is produced, and makes SCR ₁Reliably working and unlikely generation malfunction.R ₃₂And C ₈Then protect SCR ₂, character is with above-mentioned.

YM ₁And YM ₂Be two piezo-resistances, protect general supply AN load end (being the C two ends) not damage components and parts respectively because of overvoltage.D ₁₃Be fly-wheel diode, this is that the halfwave rectifier load is an inductive and must being provided with.K is a mains switch, transformer BN ₁Winding voltage 220V, N ₂Winding voltage is 13V, N ₂The 13V voltage of output is divided into two the tunnel, the one tunnel through R ₃₁Current limliting goes up (L with HB isolation and around) to coil L and receives N through knob AN open in usual again ₂The other end of winding.Knob AN and R ₃₁, whether L form simulation residue leakage current signal and detect entire circuit and work.Press AN during detection, HB promptly exports analog signal, and this signal can satisfy the sensitivity minimization requirement of entire circuit.

N ₂Another road through D ₉To D ₁₂Bridge rectifier C ₅Filtering is again through IC ₃Voltage stabilizing is 9V.R ₃₀With LED ₁Form the power supply indication, as long as the later power supply of power supply BX and K is normal, LED ₁Bright, if disconnect K or BX fusing, LED ₁Go out.

The above-mentioned high potential that relates to and electronegative potential are distinguished and only are relative on certain working point and opinion should not mix with the high electronegative potential of other working point and distinguish.

It is power ground after the voltage stabilizing that short and thick on the accompanying drawing adds black line.

This circuit external terminal is four, and NA is input, and the C two ends are output.

IC ₁For the LM324 four high guaily unit, comprise A ₁, A ₂, A ₃, A ₄

IC ₂Be the NE556 dual time base circuit.

IC ₃Be 7809 three-terminal voltage-stabilizing circuit.

The combined floodgate of this paper is the complete machine output signal, the A.C. contactor adhesive.Tripping operation disconnects for contactor.

Claims (7)

1, a kind of energy-saving earth leakage protective device, it mainly includes the testing circuit that low-voltage distributing line residue leakage current is detected and exports induced signal, to amplifying circuit, the sensitivity adjusting circuit that induced signal is amplified and regulates, the triggering drive circuit of control performer action; Feature of the present utility model is: be provided with mainly by two unidirectional controllable silicon S CR ₁, SCR ₂The control of the A.C. contactor that constitutes and DC start operation circuit, unidirectional controllable silicon S CR ₁, SCR ₂The control utmost point connects the output that triggers drive circuit respectively, unidirectional controlled extension SCR ₁Be added on the ac contactor coil exchanging the low-voltage halfwave rectifier; Unidirectional controllable silicon S CR ₂Alternating current 220V power supply halfwave rectifier is added on the ac contactor coil.

2,, it is characterized in that the prime signal amplification circuit adopts LM324 four high guaily unit integrated amplifier according to the described energy-saving earth leakage protective device of claim 1.

3,, it is characterized in that adopting 7809 circuit of three-terminal voltage-stabilizing integrated to the in addition voltage stabilizing of the output voltage of transformer time utmost point winding according to the described energy-saving earth leakage protective device of claim 1.

4,, it is characterized in that behind amplifying circuit, being provided with by D according to the described energy-saving earth leakage protective device of claim 1 ₅, D ₆And R ₁₆The NAND gate circuit that constitutes and by A ₃, A ₄The positive feedback type memory circuit that constitutes.

5,, it is characterized in that constituting 2 delay circuits respectively by two output pins of dual time-base ic according to the described energy-saving earth leakage protective device of claim 1.

6, according to the described energy-saving earth leakage protective device of claim 1, it is characterized in that at two unidirectional controllable silicon S CR ₁, SCR ₂Two ends respectively and connect by R ₃₂, C ₁₈, R _33,C ₁₃The rc protection circuit that constitutes.

7, according to the described energy-saving earth leakage protective device of claim 1, the triggering drive circuit that it is characterized in that controlling the action of performer one-way SCR can be by two triode BG ₁, BG ₂And capacitor C ₁₄Constitute.

Images