CN202616744U - Leakage protector - Google Patents

Leakage protector Download PDF

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Publication number
CN202616744U
CN202616744U CN 201220108640 CN201220108640U CN202616744U CN 202616744 U CN202616744 U CN 202616744U CN 201220108640 CN201220108640 CN 201220108640 CN 201220108640 U CN201220108640 U CN 201220108640U CN 202616744 U CN202616744 U CN 202616744U
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ground wire
output
input
resistance
circuit
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罗萱宁
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罗萱宁
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Abstract

The utility model discloses a leakage protector, which can not only prevent electric shock accidents caused by faults of electric appliances but also prevent electric shock accidents caused by accidental electrification of a ground wire. The leakage protector comprises a zero sequence current transformer which a phase line and a zero line pass through, a testing circuit, an electromagnetic releasing and locking device, a drive circuit of an electromagnetic coil of the electromagnetic releasing and locking device, a ground wire fault voltage detection circuit and a ground wire electrification detection inductor. The input ends of the ground wire fault voltage detection circuit are respectively connected with the ground wire and the zero line. The output ends of the ground wire fault voltage detection circuit are connected with second group input ends inside the drive circuit of the electromagnetic coil. The ground wire passes through the ground wire electrification detection inductor. Output ends of a secondary winding of the ground wire electrification detection inductor are respectively connected with the output ends of a secondary winding of the zero sequence current transformer. The output ends of the secondary winding of the zero sequence current transformer are further connected with first group input ends in the drive circuit of the electromagnetic coil.

Description

A kind of earth leakage protective device
Technical field
The utility model relates to Electrical Safety resist technology field, especially relates to a kind of earth leakage protective device.
Background technology
Chinese patent document CN1142618C discloses a kind of leakage protecting plug; Not only be provided with zero sequence current mutual inductor that phase line and zero line all pass on this leakage protecting plug, also be provided with the ground wire electrified detection inductor that ground wire passes; Therefore it not only can detect between load end phase line and the zero line and have or not residual current; (for example: 10mA), it will be threaded off immediately, cuts off phase line, zero line and ground wire when occurring residual current between phase, the zero line and reaching the threshold values that presets; And when the ground protection system exception causes the ground wire accident charged; It can also detect the load end ground wire has the zero accident electric current; (for example: 10mA), it also can be threaded off immediately, cuts off phase line, zero line and ground wire when ground wire unexpected electric current occurs and reaches the threshold values that presets.
By on can know; Existing earth leakage protective device is exactly must have between load end phase, the zero line must have a mind to extrinsic current on residual current or the load end ground wire and flow through and could thread off in the unexpected precondition that can thread off when charged of the electric leakage of load end fault or ground wire; So just there is following defective in existing earth leakage protective device: during use; No matter be when ground protection system ground wire disappearance (for example: the virtual connection of socket ground wire causes no ground connection) and the electric leakage of earth leakage protective device load end consuming device insulation fault; Still when ground protection system exception (for example: phase line, earth short) causes the ground wire accident charged; Dangerous voltage on the exposed metal parts band of consuming device is caused in the capital; But they all do not constitute the loop thereby also do not produce the unexpected electric current of residual current or ground wire, so, although consuming device exposed metal parts have been with dangerous voltage; But existing earth leakage protective device can not threaded off in this case automatically; Have only when human body or livestock touch these with the exposed metal parts that power on, just form the loop, earth leakage protective device is threaded off and phase line, zero line, ground wire disconnection in 0.1S thereby produce residual current or the unexpected electric current of ground wire through human body or livestock; Though in time threading off, it has protected the life security of people or livestock; But existing earth leakage protective device be in this case must be earlier through human body or livestock get an electric shock produce residual current or the unexpected electric current of ground wire and flow through human body or livestock after, it could thread off phase line, zero line, ground wire disconnection, still can cause the electric shock accidents of human body or livestock so have earth leakage protective device now.
Chinese patent document CN202142735U also discloses a kind of leakage protecting plug; Unusual and ground wire false voltage (for example: will be phase, zero, ground wire automatic disconnection before people's contact in the time of 36V) reaches predetermined ground wire false voltage value to this kind leakage protecting plug in grounding system; When the ground wire false voltage less than predetermined ground wire false voltage threshold values (for example: in the time of 36V); Leakage protecting plug just can not move, to avoid misoperation.Hence one can see that; Just there is following defective in this kind leakage protecting plug: in case when the false voltage that ground wire occurs is lower than predetermined threshold values and produces over the ground fault current; This kind leakage protecting plug but is the outage of can not tripping, so still may cause electrical fire or electric shock accidents.
Summary of the invention
The purpose of the utility model is to provide a kind of earth leakage protective device that can overcome above-mentioned existing earth leakage protective device defective; It not only can be in the phase of load end, all break off phase line contact, zero line contact and ground wire contact in time when electric leakage takes place on the zero line road, and it can also all can in time all break off phase line contact, zero line contact, ground wire contact when ground wire breaks down voltage or fault current.
The technical solution that the utility model proposed is such:
A kind of earth leakage protective device; Include zero sequence current mutual inductor, test loop, electromagnetic trip and locker that shell, phase line, zero line, ground wire, said phase line and zero line all pass; This electromagnetic trip and locker comprise solenoid and drive circuit thereof, contact; The drive circuit of said solenoid mainly is made up of rectification circuit, controllable silicon; Also be provided with ground wire false voltage testing circuit and ground wire electrified detection inductor; One input of said ground wire false voltage testing circuit is connected with zero line with described ground wire respectively with another input; The output of said ground wire false voltage testing circuit is connected with the 2nd group of input in the drive circuit of said solenoid; Said ground wire passes said ground wire electrified detection inductor, and an output of said ground wire electrified detection inductor secondary winding is connected with another output with an output of said zero sequence current mutual inductor secondary winding respectively with another output, and the output of said zero sequence current mutual inductor secondary winding is connected with the 1st group of input in the drive circuit of said solenoid.
Said ground wire false voltage testing circuit mainly detects inductor by the 1st Resistor-Capacitor Unit, weak current to be formed, and said weak current detects inductor and is provided with elementary winding, secondary winding, iron core, and said elementary winding and secondary winding are all on said iron core.
Said ground wire false voltage testing circuit mainly is made up of the 2nd Resistor-Capacitor Unit, photoelectrical coupler, the 1st triode, the 1st resistance, the 6th resistance.
In the drive circuit of said solenoid, also be provided with the 1st amplifying circuit, the 1st diode, the 2nd amplifying circuit, the 2nd diode; The 1st group of input in the drive circuit of said solenoid is the input of said the 1st amplifying circuit; The 2nd group of input in the drive circuit of said solenoid is the input of said the 2nd amplifying circuit; One output of said zero sequence current mutual inductor secondary winding is connected with another input with an input of said the 1st amplifying circuit respectively with another output; The detection loop that said weak current detection elementary winding of inductor and said the 1st Resistor-Capacitor Unit are in series is connected between described ground wire and the zero line; The output that said weak current detects the inductor secondary winding is connected with another input with an input of the 2nd amplifying circuit respectively with another output; Said the 1st amplifying circuit triggers output and is connected with said the 1st diode cathode; Said the 2nd amplifying circuit triggers output and is connected with said the 2nd diode cathode, and the 1st diode cathode, the 2nd diode cathode are connected with said controllable silicon trigger electrode.
In the drive circuit of said solenoid, also be provided with the 1st amplifying circuit, the 1st diode; The 1st group of input in the drive circuit of said solenoid is the input of said the 1st amplifying circuit; The 2nd group of input in the drive circuit of said solenoid is said silicon controlled trigger electrode and negative electrode; One output of said zero sequence current mutual inductor secondary winding is connected with another input with an input of said the 1st amplifying circuit respectively with another output; Said the 1st amplifying circuit triggers output and is connected with the 1st diode cathode; The detection loop that is in series by an input and another input of said the 2nd Resistor-Capacitor Unit and photoelectrical coupler is connected between described ground wire and the zero line; The collector electrode of said photoelectrical coupler one output, the 1st triode and the power end of said the 1st amplifying circuit are connected; Another output of said photoelectrical coupler is connected with base stage, the 1st resistance one end of said the 1st triode, and the 1st resistance other end is connected with said rectification circuit output end negative pole, and the emitter of the 1st triode is connected with said controllable silicon trigger electrode, the 1st diode cathode, the 6th resistance one end; The 6th resistance other end is connected with the controllable silicon negative electrode, and the silicon controlled anode is connected with negative pole with the positive pole of rectification circuit output end respectively with negative electrode.
In the drive circuit of said solenoid, also be provided with the 1st amplifying circuit, the 1st diode, voltage comparator circuit, the 2nd resistance, the 3rd resistance, the 4th resistance, voltage stabilizing didoe, unidirectional breakover element; The 2nd resistance one end is connected with rectification circuit output end is anodal; The 2nd resistance other end is connected with the voltage stabilizing didoe negative pole; Voltage stabilizing didoe is anodal to be connected with the rectification circuit output end negative pole; The 1st group of input in the drive circuit of said solenoid is the input of said the 1st amplifying circuit; The input that the 2nd group of input in the drive circuit of said solenoid is said voltage comparator circuit and the negative pole of said rectification circuit output end; One output of zero sequence current mutual inductor secondary winding is connected with another input with an input of the 1st amplifying circuit respectively with another output; The 1st amplifying circuit triggers output and is connected with the 1st diode cathode, and the 1st diode cathode is connected with said controllable silicon trigger electrode, and the detection loop that is formed by said the 1st Resistor-Capacitor Unit and the elementary windings in series of said weak current detection inductor is connected between described ground wire and the zero line; Said weak current detects inductor secondary winding one output and is connected with said voltage comparator circuit one input; Said weak current detects another output of inductor secondary winding and is connected with said rectification circuit output end negative pole, and the 3rd resistance one end is connected with the voltage stabilizing didoe negative pole, and the 3rd resistance other end is connected with the 4th resistance one end, another input of voltage comparator circuit respectively; The 4th resistance other end is connected with voltage stabilizing didoe is anodal, and the voltage comparator circuit output is connected with the controllable silicon trigger electrode through unidirectional breakover element.
The the said the 1st or the 2nd Resistor-Capacitor Unit adopts the assembly of resistance or electric capacity or resistance and electric capacity.
Said voltage comparator circuit adopts voltage comparator exclusive disjunction amplifier.
In an output link circuit of output of said ground wire electrified detection inductor secondary winding and said zero sequence current mutual inductor secondary winding, also be in series with the 5th resistance, another output of ground wire electrified detection inductor secondary winding directly is connected with another output of zero sequence current mutual inductor secondary winding.
Said unidirectional breakover element is the 3rd diode or the 2nd triode.
Compared with prior art, the utlity model has following beneficial effect:
(1), the earth leakage protective device of the utility model not only can be at break down voltage and before people touch, breaking off when reaching reservation threshold of ground wire; And can also be lower than break down electric current and can make the timely automatic disconnection of leakage protecting plug equally when reaching reservation threshold of reservation threshold and accident at the false voltage that ground wire occurs, thereby avoid the electrical fire accident and cause therefrom get an electric shock, the generation of electric leakage accident.
(2), the earth leakage protective device of the utility model provides protection in the time of can also breaking down electric leakage for the phase of load end, consuming device on the zero line road, all break off phase line contact, zero line contact, ground wire contact.
The earth leakage protective device of the utility model is mainly used in mainly making leakage protecting plug or earth leakage protective socket on the earth leakage protective of various household electrical appliance.
Description of drawings
Fig. 1 is the electrical principle sketch map of the earth leakage protective device of the 1st embodiment of the utility model.
Fig. 2 is the electrical principle sketch map of the earth leakage protective device of the 2nd embodiment of the utility model.
Fig. 3 is the electrical principle sketch map of the earth leakage protective device of the 3rd embodiment of the utility model.
Embodiment
Through following embodiment the utility model is done further to set forth in detail.
Embodiment 1
Referring to shown in Figure 1; A kind of earth leakage protective device, it mainly is made up of phase line 8, zero line 9, ground wire the 10, the 1st diode the 20, the 2nd diode 21, ground wire electrified detection inductor the 23, the 5th resistance 22, electromagnetic trip and locker that the phase line 5 of shell, power end, zero line 6, ground wire 7, rectification circuit 12, controllable silicon the 13, the 1st amplifying circuit the 14, the 2nd amplifying circuit 19, zero sequence current mutual inductor 15, test loop 16, weak current detect inductor the 18, the 1st Resistor-Capacitor Unit 17, load end.Electromagnetic trip and locker mainly are made up of solenoid 11 and drive circuit, phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4, spring, the push rod that resets.
In the present embodiment; The 1st group of input in the drive circuit of solenoid 11 is the input of the 1st amplifying circuit 14; The 2nd group of input in the drive circuit of solenoid 11 is the input of the 2nd amplifying circuit 19; One output of zero sequence current mutual inductor 15 secondary winding is connected with another input with an input of the 1st amplifying circuit 14 respectively with another output; After detecting inductor 18 elementary windings and the 1st Resistor-Capacitor Unit 17 is connected, weak current is connected between the ground wire 7 and zero line 6 of power end; The output that weak current detects inductor 18 secondary winding is connected with another input with an input of the 2nd amplifying circuit 19 respectively with another output; The 1st amplifying circuit 14 triggers output and 20 anodal connections of the 1st diode; The 2nd amplifying circuit 19 triggers output and 21 anodal connections of the 2nd diode, and the 1st diode 20 negative poles, the 2nd diode 21 negative poles are connected with controllable silicon 13 trigger electrodes, and controllable silicon 13 anodes, negative electrode are connected with negative pole (-) with the positive pole (+) of rectification circuit 12 outputs respectively.
In the present embodiment; Ground wire 10 passes ground wire electrified detection inductor 23; In the link circuit of ground wire electrified detection inductor 23 secondary winding, one output and zero sequence current mutual inductor 15 secondary winding one output, be in series with the 5th resistance 22; One output of ground wire electrified detection inductor 23 secondary winding is connected with the 5th resistance 22 1 ends; The 5th resistance 22 other ends are connected with an output of zero sequence current mutual inductor 15 secondary winding, and another output of ground wire electrified detection inductor 23 secondary winding directly is connected with another output of zero sequence current mutual inductor 15 secondary winding.
Also can change into and the 5th resistance 22 in the link circuit of another output of another output that is connected in series in ground wire electrified detection inductor 23 secondary winding and zero sequence current mutual inductor 15 secondary winding; At this moment; The 5th resistance 22 1 ends are connected with another output of ground wire electrified detection inductor 23 secondary winding; The 5th resistance 22 other ends are connected with another output of zero sequence current mutual inductor 15 secondary winding, and an output of ground wire electrified detection inductor 23 secondary winding directly is connected with an output of zero sequence current mutual inductor 15 secondary winding.
Can also cancel the 5th resistance 22, at this moment, an output of ground wire electrified detection inductor 23 secondary winding directly is connected with another output with an output of zero sequence current mutual inductor 15 secondary winding respectively with another output.
Resistance value through suitable adjustment the 5th resistance 22 can reach adjustment ground wire fault current operating value or the parameter configuration through suitable adjustment ground wire electrified detection inductor 23 can reach adjustment ground wire fault current operating value too; And can also be through the resistance value of suitable adjustment the 5th resistance 22 and the parameter configuration of ground wire electrified detection inductor 23 reach adjustment ground wire fault current operating value simultaneously; Therefore, the 5th resistance 22 can be neatly determined whether that according to actual conditions needs select for use during practical implementation.
In the present embodiment; The 1st Resistor-Capacitor Unit 17 is a resistance; Also can adopt electric capacity or resistance and capacitance component; Weak current detects the detection loop that inductor 18 elementary windings and the 1st Resistor-Capacitor Unit 17 be in series and is connected between the ground wire 7 and zero line 6 of power end, also can detect this between ground wire 10 and zero line 9 that loop is connected load end.
During use; Press the push rod that resets of earth leakage protective device; Phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2 and ground wire contact 3 and 4 are all normally connected; The phase line 8 of load end, zero line 9, ground wire 10 are connected with phase line 5, zero line 6, the ground wire 7 of power end respectively; Ground wire 7 and 10 is because the effects of ground connection are clamped at about zero volt voltage, and zero line 6 and 9 also is about zero volt simultaneously, and the electric current that is detected the detection loop that inductor 18 elementary windings and the 1st Resistor-Capacitor Unit 17 be composed in series by weak current does not just reach the threshold values (for example: 10 microamperes) that presets; Earth leakage protective device just remains on the "on" position that resets like this, thereby for the power supply of the consuming device of its lower end with ground connection is provided.
During use; If the consuming device fault on the phase line of load end 8, the zero line 9 electric leakage and under the normal situation of ground protection system; Can produce a residual current through ground wire 10 and 7; Zero sequence current mutual inductor 15 can detect the residual current between phase, the zero line and export a signal and give the 1st amplifying circuit 14; And when residual current reached predefined threshold values (for example: 10 milliamperes), the 1st amplifying circuit 14 output signals then oppositely ended the 1st diode 20 conductings the 2nd diode 21, thereby trigger controllable silicon 13 conductings; Earth leakage protective device is threaded off, and before people touch consuming device, just can in time all break off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4; And if the phase line 8 of load end, the consuming device fault on the zero line 9 electric leakage and when not having ground connection (for example: the ground wire virtual connection causes no ground connection on the socket) in the ground protection system; Metal parts that consuming device exposes and earth leakage protective device ground wire 10 and 7 all can be with dangerous voltage; Being connected weak current between earth leakage protective device power end ground wire 7 and the zero line 6 detects inductor 18 elementary windings and just has a weak current and flow through; Weak current detects inductor 18 secondary winding can export a signal to the 2nd amplifying circuit 19; When the ground wire false voltage (for example: in the time of 36V) reaches predetermined threshold voltage; The weak current that detects in the loop also reaches predetermined threshold values (for example: 10 microamperes); Thereby make the 2nd amplifying circuit 19 output triggering signals give the 2nd diode 21 and trigger controllable silicon 13 conductings, the 1st diode 20 then oppositely ends, and leakage protecting plug is threaded off; Before people touch consuming device, just can in time all break off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4, thereby protect people's Electrical Safety better.
During use; If the ground protection system takes place to cause unusually ground wire 7 and 10 accidents with going up dangerous false voltage; Ground wire 7 and the weak current between the zero line 6 that is connected power end like this detects inductor 18 elementary windings and just has a weak current and flow through; Weak current detects signal of inductor 18 secondary winding output and amplifies for the 2nd amplifying circuit 19; (for example: in the time of 36V), the weak current that detects in the loop also reaches predetermined threshold values (for example: 10 microamperes), thereby makes the 2nd amplifying circuit 19 output triggering signals and the 2nd diode 21 conductings the 1st diode 20 is then oppositely ended when the ground wire false voltage reaches predetermined threshold voltage; Thereby trigger controllable silicon 13 conductings; The earth leakage protective device dropout just can in time all be broken off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4 before people touch consuming device, thereby had protected people's safety better.
During use; When grounding system take place to cause unusually ground wire 7 and 10 accidents with on when producing over the ground fault current less than the ground wire false voltage operating value that presets and ground wire; The fault current that then flows through ground wire 10 will be detected and makes ground wire electrified detection inductor 23 secondary winding output signal to the 1st amplifying circuit 14 by ground wire electrified detection inductor 23 at once; When the fault current that flows through ground wire 10 reaches predetermined threshold values; The 1st amplifying circuit 14 output triggering signals are given the 1st diode 20 and are triggered controllable silicon 13 conductings; Earth leakage protective device is threaded off phase line contact 1-1 and 1-2, zero line contact 1-2 and 2-2, ground wire contact 3 and was opened in 4 minutes, thereby has ensured people's safety better.
Embodiment 2
Referring to shown in Figure 2; A kind of earth leakage protective device, it mainly is made up of the phase line 8 of the phase line 5 of shell, power end, zero line 6, ground wire 7, rectification circuit 12, controllable silicon the 13, the 1st amplifying circuit 14, zero sequence current mutual inductor 15, test loop the 16, the 2nd Resistor-Capacitor Unit 33, load end, zero line 9, ground wire the 10, the 1st diode 20, ground wire electrified detection inductor the 23, the 5th resistance 22, photoelectrical coupler the 24, the 1st resistance the 25, the 1st triode the 26, the 6th resistance 34, electromagnetic trip and locker.Electromagnetic trip and locker mainly are made up of solenoid 11 and drive circuit, phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4, spring, the push rod that resets.
In the present embodiment; The 1st group of input in the drive circuit of solenoid 11 is the input of the 1st amplifying circuit 14; The 2nd group of trigger electrode and the negative electrode that input is a controllable silicon 13 in the drive circuit of solenoid 11; One output of zero sequence current mutual inductor 15 secondary winding is connected with another input with an input of the 1st amplifying circuit 14 respectively with another output; The 1st amplifying circuit 14 triggers output and 20 anodal connections of the 1st diode; The 1st diode 20 negative poles are connected with emitter, the 6th resistance 34 1 ends of controllable silicon 13 trigger electrodes, the 1st triode 26, and the 6th resistance 34 other ends are connected with controllable silicon 13 negative electrodes, and the anode of controllable silicon 13, negative electrode are connected with negative pole (-) with the positive pole (+) of rectification circuit 12 outputs respectively.
In the present embodiment; The detection loop that is composed in series by an input and another input of the 2nd Resistor-Capacitor Unit 33 and photoelectrical coupler 24 is connected between the ground wire 7 and zero line 6 of power end; One output of photoelectrical coupler 24, the collector electrode of the 1st triode 26 all with the power end of the 1st amplifying circuit 14 (+VS) be connected; Another output of photoelectrical coupler 24 is connected with the base stage of the 1st resistance 25 1 ends, the 1st triode 26, and the 1st resistance 25 other ends are connected with the ground end (GND) of the 1st amplifying circuit 14, the negative pole (-) of rectification circuit 12 outputs.
In the present embodiment; Ground wire 10 passes ground wire electrified detection inductor 23; One output of ground wire electrified detection inductor 23 secondary winding is connected with the 5th resistance 22 1 ends; The 5th resistance 22 other ends are connected with an output of zero sequence current mutual inductor 15 secondary winding, and another output of ground wire electrified detection inductor 23 secondary winding is connected with another output of zero sequence current mutual inductor 15 secondary winding.
Also can change the 5th resistance 22 in the link circuit of another output of another output that is connected in series in ground wire electrified detection inductor 23 and zero sequence current mutual inductor 15 secondary winding into; At this moment; The 5th resistance 22 1 ends are connected with another output of ground wire electrified detection inductor 23 secondary winding; The 5th resistance 22 other ends are connected with another output of zero sequence current mutual inductor 15 secondary winding, and an output of ground wire electrified detection inductor 23 secondary winding directly is connected with an output of zero sequence current mutual inductor 15 secondary winding.
Can also cancel the 5th resistance 22, at this moment, an output of ground wire electrified detection inductor 23 secondary winding directly is connected with another output with an output of zero sequence current mutual inductor 15 secondary winding respectively with another output.
Resistance value through suitable adjustment the 5th resistance 22 can reach adjustment ground wire fault current operating value or the parameter configuration through suitable adjustment ground wire electrified detection inductor 23 can reach adjustment ground wire fault current operating value too; And can also be through the resistance value of suitable adjustment the 5th resistance 22 and the parameter configuration of ground wire electrified detection inductor 23 reach adjustment ground wire fault current operating value simultaneously; Therefore, the 5th resistance 22 can be neatly determined whether that according to actual conditions needs select for use during practical implementation.
In the present embodiment; The 2nd Resistor-Capacitor Unit 33 is an electric capacity; Also can adopt resistance or resistance and capacitance component; The detection loop that is in series by an input of photoelectrical coupler 24 and another input and the 2nd Resistor-Capacitor Unit 33 is connected between the ground wire 7 and zero line 6 of power end, also can detect this between ground wire 10 and zero line 9 that loop is connected load end.
During use; Press the push rod that resets of earth leakage protective device; Phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2 and ground wire contact 3 and 4 are all normally connected; The phase line 8 of load end, zero line 9, ground wire 10 are connected with phase line 5, zero line 6, the ground wire 7 of power end respectively, and ground wire 7 and 10 is because the effect of ground connection is clamped at about zero volt voltage, and zero line 6 and 9 also is about zero volt simultaneously; The electric current that being connected ground wire 7 and the photoelectrical coupler between the zero line 6 24 inner light-emitting components of leakage protecting plug power end does not so just have electric current to flow through or flow through does not reach the threshold values (for example: 10 microamperes) that presets; Photoelectrical coupler 24 can not make 26 conductings of the 1st triode, and earth leakage protective device just remains on the "on" position that resets, thereby for the power supply of the consuming device of its lower end with ground connection is provided.
During use; If the consuming device fault on the phase line of load end 8, the zero line 9 electric leakage and in the normal situation of ground protection system following time; Can produce a residual current through ground wire 10 and 7; Zero sequence current mutual inductor 15 can detect the residual current between phase, the zero line and export a signal and give the 1st amplifying circuit 14; And when residual current reached predefined threshold values (for example: 10 milliamperes), the 1st amplifying circuit 14 output triggering signals made 20 conductings of the 1st diode, thereby trigger controllable silicon 13 conductings; Earth leakage protective device is threaded off, and before people touch consuming device, just can in time all break off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4; And if the phase line 8 of load end, the consuming device fault on the zero line 9 electric leakage and when not having ground connection (for example: the ground wire virtual connection causes no ground connection on the socket) in the ground protection system; Metal parts that consuming device exposes and earth leakage protective device ground wire 10 and 7 all can be with dangerous voltage; The photoelectrical coupler 24 inner light-emitting components that are connected between earth leakage protective device power end ground wire 7 and the zero line 6 will be luminous; And the exciting light electric coupling with make it output signal to the base stage of triode 26; When the ground wire false voltage (for example: in the time of 36V) reaches predetermined threshold voltage; Photoelectrical coupler 24 triggers controllable silicon 13 conductings with regard to making 26 conductings of the 1st triode, and the 1st diode 20 then oppositely ends, and leakage protecting plug is threaded off; Before people touch consuming device, just can in time all break off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4, thereby protect people's Electrical Safety better.
During use; If the ground protection system takes place to cause unusually ground wire 7 and 10 accidents with going up dangerous false voltage; The ground wire 7 and the 24 inner light-emitting components of the photoelectrical coupler between the zero line 6 that are connected power end like this will be luminous; Photoelectrical coupler 24 will output signal to the base stage of the 1st triode 26; (for example: in the time of 36V), photoelectrical coupler 24 triggers controllable silicon 13 conductings with regard to making 26 conductings of the 1st triode, and earth leakage protective device is threaded off when the ground wire false voltage reaches predetermined threshold voltage; Touch people and just can in time all break off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4 before the consuming device, thereby protected people's safety better.
During use; When grounding system takes place to cause unusually ground wire 7 and 10 accidents when going up less than the unexpected over the ground generation fault current of the ground wire false voltage that presets and ground wire; The fault current that then flows through ground wire 10 will be detected and makes ground wire electrified detection inductor 23 secondary winding output signal to the 1st amplifying circuit 14 by ground wire electrified detection inductor 23 at once; When the electric current of ground wire 10 Leaked Current of Line to Ground reaches predetermined threshold values; The 1st amplifying circuit 14 output triggering signals are given the 1st diode 20 and are triggered controllable silicon 13 conductings; Leakage protecting plug is threaded off phase line contact 1-1 and 1-2, zero line contact 1-2 and 2-2, ground wire contact 3 and was opened in 4 minutes, thereby has ensured people's safety better.
Embodiment 3
Referring to shown in Figure 3; A kind of earth leakage protective device, it mainly is made up of phase line 8, zero line 9, ground wire the 10, the 1st diode 20, ground wire electrified detection inductor the 23, the 2nd resistance 28, voltage stabilizing didoe the 29, the 3rd resistance the 30, the 4th resistance 31, voltage comparator circuit the 27, the 3rd diode 32, electromagnetic trip and locker that the phase line 5 of shell, power end, zero line 6, ground wire 7, rectification circuit 12, controllable silicon the 13, the 1st amplifying circuit 14, zero sequence current mutual inductor 15, test loop 16, weak current detect inductor the 18, the 1st Resistor-Capacitor Unit 17, load end.Electromagnetic trip and locker mainly are made up of solenoid 11 and drive circuit, phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4, spring, the push rod that resets.
In the present embodiment; The 1st group of input in the drive circuit of solenoid 11 is the input of the 1st amplifying circuit 14; The 2nd group of input in the drive circuit of solenoid 11 is respectively an input (+) of voltage comparator circuit 27 and the negative pole (-) of rectification circuit 12 outputs; One output of zero sequence current mutual inductor 15 secondary winding is connected with another input with an input of the 1st amplifying circuit 14 respectively with another output; The 1st amplifying circuit 14 triggers output and 20 anodal connections of the 1st diode; The 1st diode 20 negative poles are connected with controllable silicon 13 trigger electrodes, and the anode of controllable silicon 13, negative electrode are connected with negative pole (-) with the positive pole (+) of rectification circuit 12 outputs respectively.
In the present embodiment; The 2nd resistance 28 1 ends are connected with the positive pole (+) of rectification circuit 12 outputs; The 2nd resistance 28 other ends are connected with voltage stabilizing didoe 29 negative poles, the 3rd resistance 30 1 ends; Voltage stabilizing didoe 29 positive poles are connected with negative pole (-), the 4th resistance 31 other ends of rectification circuit 12 outputs; The 3rd resistance 30 other ends are connected with another input (-) of the 4th resistance 31 1 ends, voltage comparator circuit 27; The detection loop of being made up of weak current detection inductor 18 elementary windings and the 1st Resistor-Capacitor Unit 17 is connected between the ground wire 10 and zero line 9 of load end, and another output that weak current detects inductor 18 secondary winding is connected with the negative pole (-) of voltage stabilizing didoe 29 positive poles, rectification circuit 12 outputs, and the output that weak current detects inductor 18 secondary winding is connected with an input (+) of voltage comparator circuit 27; Voltage comparator circuit 27 outputs and 32 anodal connections of the 3rd diode, the 3rd diode 32 negative poles are connected with controllable silicon 13 trigger electrodes.
In the present embodiment, unidirectional breakover element is the 3rd diode 32.
Also can change unidirectional breakover element into the 3rd diode 32 that NPN the 2nd triode 35 replaces present embodiment; At this moment; NPN the 2nd triode 35 base stages are connected with voltage comparator circuit 27 outputs; NPN the 2nd triode 35 collector electrodes are connected with voltage stabilizing didoe 29 negative poles, and NPN the 2nd triode 35 emitters are connected with controllable silicon 13 trigger electrodes, shown in the concrete method of attachment of the 2nd triode 35 can connect referring to dotted line corresponding in Fig. 3.
In the present embodiment, ground wire 10 passes ground wire electrified detection inductor 23, and an output of ground wire electrified detection inductor 23 secondary winding directly is connected with another output with an output of zero sequence circuit instrument transformer 15 secondary winding respectively with another output.
Also can select the current-limiting resistance of in the link circuit of an output of ground wire electrified detection inductor 23 secondary winding and an output of zero sequence current mutual inductor 15 secondary winding, connecting for use; At this moment; One output of ground wire electrified detection inductor 23 secondary winding is connected with current-limiting resistance one end; The current-limiting resistance other end is connected with an output of zero sequence current mutual inductor 15 secondary winding, and another output of ground wire electrified detection inductor 23 secondary winding directly is connected with another output of zero sequence current mutual inductor 15 secondary winding.
Can also select the current-limiting resistance of in the link circuit of another outputs of ground wire electrified detection inductor 23 secondary winding and another output of zero sequence current mutual inductor 15 secondary winding, connecting for use; Another output of ground wire electrified detection inductor 23 secondary winding is connected with current-limiting resistance one end; The current-limiting resistance other end is connected with another output of zero sequence current mutual inductor 15 secondary winding, and an output of ground wire electrified detection inductor 23 secondary winding directly is connected with an output of zero sequence current mutual inductor 15 secondary winding.
The resistance value of the current-limiting resistance of being connected with ground wire electrified detection inductor 23 through suitable adjustment just can reach adjustment ground wire fault current operating value or the parameter configuration through suitable adjustment ground wire electrified detection inductor 23 can reach adjustment ground wire fault current operating value too; And the parameter configuration of the resistance value of the current-limiting resistance that can also be connected with ground wire electrified detection inductor 23 through adjustment simultaneously suitably and ground wire electrified detection inductor 23 reaches and adjusts ground wire fault current operating value; Therefore, pair current-limiting resistance of being connected with ground wire electrified detection inductor 23 can be neatly determines whether that according to actual conditions needs select for use during practical implementation.
In the present embodiment; The 1st Resistor-Capacitor Unit 17 is a resistance; Also can adopt electric capacity or resistance and capacitance component; Weak current detects the detection loop that inductor 18 elementary windings and the 1st Resistor-Capacitor Unit 17 be in series and is connected between the ground wire 10 and zero line 9 of load, also can detect this between ground wire 7 and zero line 6 that loop is connected power end.
In the present embodiment, voltage comparator circuit 27 is selected voltage comparator for use, also can select operational amplifier for use.
During use; Press the push rod that resets of earth leakage protective device; Phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2 and ground wire contact 3 and 4 are all normally connected, and the phase line 8 of load end, zero line 9, ground wire 10 are connected with phase line 5, zero line 6, the ground wire 7 of power end respectively, and ground wire 7 and 10 is because the effect of ground connection is clamped at about zero volt voltage; Zero line 6 and 9 also is about zero volt simultaneously; The electric current that ground wire 10 and the weak current between the zero line 9 that is connected the earth leakage protective device load end like this detects inductor 18 elementary windings does not just have electric current to flow through or flow through does not reach the threshold values (for example: 10 microamperes) that presets, and the voltage of signals of an input (+) of sending into voltage comparator circuit 27 is just less than the reference voltage of another input (-) of voltage comparator circuit, and voltage comparator circuit 27 does not have signal to export; The 3rd diode 32 ends; Controllable silicon 13 ends, and earth leakage protective device just remains on the "on" position that resets, thereby for the power supply of the consuming device of its lower end with ground connection is provided.
During use; If the consuming device fault on the phase line of load end 8, the zero line 9 electric leakage and under the normal situation of ground protection system; Can produce a residual current through ground wire 10 and 7; Zero sequence current mutual inductor 15 can detect the residual current between phase, the zero line and export a signal and give the 1st amplifying circuit 14, and when residual current reached predefined threshold values (for example: 10 milliamperes), the 1st amplifying circuit 14 output signals made 20 conductings of the 1st diode and trigger controllable silicon 13 conductings; Earth leakage protective device is threaded off, and before people touch consuming device, just can in time all break off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4; And if the phase line 8 of load end, the consuming device fault on the zero line 9 electric leakage and when not having ground connection (for example: the ground wire virtual connection causes no ground connection on the socket) in the ground protection system; Metal parts and the ground wire on the earth leakage protective device 10 and 7 that consuming device exposes all can be with dangerous voltage; Ground wire 10 and the weak current between the zero line 9 that is connected the load end of earth leakage protective device detects inductor 18 elementary windings and just has a weak current and flow through; Weak current detects inductor 18 secondary winding can export the input (+) that a signal is given voltage comparator circuit 27; When the ground wire false voltage (for example: in the time of 36V) reaches predetermined threshold voltage; The voltage of signals of an input (+) of sending into voltage comparator circuit 27 is just greater than the reference voltage of another input (-) of voltage comparator circuit 27; Voltage comparator circuit 27 outputs output signal to the 3rd diode 32 immediately and trigger controllable silicon 13 conductings; Earth leakage protective device is threaded off, and before people touch consuming device, just can in time all break off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4, thereby protect people's Electrical Safety better.
During use; If the ground protection system takes place to cause unusually ground wire 7 and 10 accidents with going up dangerous false voltage; Ground wire 10 and the weak current between the zero line 9 that is connected load end like this detects inductor 18 elementary windings and just has a weak current and flow through; Weak current detects the input (+) that signal of inductor 18 secondary winding output is given voltage comparator circuit 27; When the ground wire false voltage (for example: in the time of 36V) reaches predetermined threshold voltage; Send into the reference voltage of the signal voltage of voltage comparator circuit 27 1 inputs (+) greater than voltage comparator circuit 27 another inputs (-), voltage comparator circuit 27 outputs will output signal to the 3rd diode 32 and trigger controllable silicon 13 conductings, and earth leakage protective device is threaded off; Touch people and just can in time all break off phase line contact 1-1 and 2-1, zero line contact 1-2 and 2-2, ground wire contact 3 and 4 before the consuming device, thereby protected people's safety better.
During use; When grounding system takes place to cause unusually ground wire 7 and 10 accidents when going up less than ground wire false voltage that presets and unexpected over the ground generation fault current; The fault current that then flows through ground wire 10 will be detected and makes ground wire electrified detection inductor 23 secondary winding output signal to the 1st amplifying circuit 14 by ground wire electrified detection inductor 23 at once; When the fault current that flows through ground wire 10 reaches predetermined threshold values; The 1st amplifying circuit 14 output triggering signals are given the 1st diode 20 and are triggered controllable silicon 13 conductings; Earth leakage protective device is threaded off phase line contact 1-1 and 1-2, zero line contact 1-2 and 2-2, ground wire contact 3 and was opened in 4 minutes, thereby has ensured people's safety better.

Claims (13)

1. earth leakage protective device; Include zero sequence current mutual inductor, test loop, electromagnetic trip and locker that shell, phase line, zero line, ground wire, said phase line and zero line all pass; This electromagnetic trip and locker comprise solenoid and drive circuit thereof, contact; The drive circuit of said solenoid mainly is made up of rectification circuit, controllable silicon; It is characterized in that: also be provided with ground wire false voltage testing circuit and ground wire electrified detection inductor; One input of said ground wire false voltage testing circuit is connected with zero line with described ground wire respectively with another input; The output of said ground wire false voltage testing circuit is connected with the 2nd group of input in the drive circuit of said solenoid; Said ground wire passes said ground wire electrified detection inductor, and an output of said ground wire electrified detection inductor secondary winding is connected with another output with an output of said zero sequence current mutual inductor secondary winding respectively with another output, and the output of said zero sequence current mutual inductor secondary winding is connected with the 1st group of input in the drive circuit of said solenoid.
2. earth leakage protective device according to claim 1; It is characterized in that: said ground wire false voltage testing circuit mainly detects inductor by the 1st Resistor-Capacitor Unit, weak current and forms; Said weak current detects inductor and is provided with elementary winding, secondary winding, iron core, and said elementary winding and secondary winding are all on said iron core.
3. earth leakage protective device according to claim 1 is characterized in that: said ground wire false voltage testing circuit mainly is made up of the 2nd Resistor-Capacitor Unit, photoelectrical coupler, the 1st triode, the 1st resistance, the 6th resistance.
4. earth leakage protective device according to claim 1 and 2 is characterized in that: in the drive circuit of said solenoid, also be provided with the 1st amplifying circuit, the 1st diode, the 2nd amplifying circuit, the 2nd diode; The 1st group of input in the drive circuit of said solenoid is the input of said the 1st amplifying circuit, and the 2nd group of input in the drive circuit of said solenoid is the input of said the 2nd amplifying circuit; One output of said zero sequence current mutual inductor secondary winding is connected with another input with an input of said the 1st amplifying circuit respectively with another output; The detection loop that said weak current detection elementary winding of inductor and said the 1st Resistor-Capacitor Unit are in series is connected between described ground wire and the zero line; The output that said weak current detects the inductor secondary winding is connected with another input with an input of the 2nd amplifying circuit respectively with another output; Said the 1st amplifying circuit triggers output and is connected with said the 1st diode cathode; Said the 2nd amplifying circuit triggers output and is connected with said the 2nd diode cathode, and the 1st diode cathode, the 2nd diode cathode are connected with said controllable silicon trigger electrode.
5. according to claim 1 or 3 described earth leakage protective devices, it is characterized in that: in the drive circuit of said solenoid, also be provided with the 1st amplifying circuit, the 1st diode; The 1st group of input in the drive circuit of said solenoid is the input of said the 1st amplifying circuit, and the 2nd group of input in the drive circuit of said solenoid is said silicon controlled trigger electrode and negative electrode; One output of said zero sequence current mutual inductor secondary winding is connected with another input with an input of said the 1st amplifying circuit respectively with another output; Said the 1st amplifying circuit triggers output and is connected with the 1st diode cathode; The detection loop that is in series by an input and another input of said the 2nd Resistor-Capacitor Unit and photoelectrical coupler is connected between described ground wire and the zero line; The collector electrode of said photoelectrical coupler one output, the 1st triode and the power end of said the 1st amplifying circuit are connected; Another output of said photoelectrical coupler is connected with base stage, the 1st resistance one end of said the 1st triode; The 1st resistance other end is connected with said rectification circuit output end negative pole; The emitter of the 1st triode is connected with said controllable silicon trigger electrode, the 1st diode cathode, the 6th resistance one end, and the 6th resistance other end is connected with the controllable silicon negative electrode, and the silicon controlled anode is connected with negative pole with the positive pole of rectification circuit output end respectively with negative electrode.
6. earth leakage protective device according to claim 1 and 2; It is characterized in that: in the drive circuit of said solenoid, also be provided with the 1st amplifying circuit, the 1st diode, voltage comparator circuit, the 2nd resistance, the 3rd resistance, the 4th resistance, voltage stabilizing didoe, unidirectional breakover element; The 2nd resistance one end is connected with rectification circuit output end is anodal; The 2nd resistance other end is connected with the voltage stabilizing didoe negative pole; Voltage stabilizing didoe is anodal to be connected with the rectification circuit output end negative pole; The 1st group of input in the drive circuit of said solenoid is the input of said the 1st amplifying circuit, the input that the 2nd group of input in the drive circuit of said solenoid is said voltage comparator circuit and the negative pole of said rectification circuit output end; One output of zero sequence current mutual inductor secondary winding is connected with another input with an input of the 1st amplifying circuit respectively with another output; The 1st amplifying circuit triggers output and is connected with the 1st diode cathode; The 1st diode cathode is connected with said controllable silicon trigger electrode; The detection loop that is formed by said the 1st Resistor-Capacitor Unit and the elementary windings in series of said weak current detection inductor is connected between described ground wire and the zero line; Said weak current detects inductor secondary winding one output and is connected with said voltage comparator circuit one input; Said weak current detects another output of inductor secondary winding and is connected with said rectification circuit output end negative pole, and the 3rd resistance one end is connected with the voltage stabilizing didoe negative pole, and the 3rd resistance other end is connected with the 4th resistance one end, another input of voltage comparator circuit respectively; The 4th resistance other end is connected with voltage stabilizing didoe is anodal, and the voltage comparator circuit output is connected with the controllable silicon trigger electrode through unidirectional breakover element.
7. according to claim 2 or 3 described earth leakage protective devices, it is characterized in that: the said the 1st or the 2nd Resistor-Capacitor Unit adopts the assembly of resistance or electric capacity or resistance and electric capacity.
8. earth leakage protective device according to claim 6 is characterized in that: said voltage comparator circuit adopts voltage comparator exclusive disjunction amplifier.
9. earth leakage protective device according to claim 1; It is characterized in that: in an output link circuit of output of said ground wire electrified detection inductor secondary winding and said zero sequence current mutual inductor secondary winding, also be in series with the 5th resistance, another output of ground wire electrified detection inductor secondary winding directly is connected with another output of zero sequence current mutual inductor secondary winding.
10. earth leakage protective device according to claim 6 is characterized in that: said unidirectional breakover element is the 3rd diode or the 2nd triode.
11. earth leakage protective device according to claim 4 is characterized in that: said the 1st Resistor-Capacitor Unit adopts the assembly of resistance or electric capacity or resistance and electric capacity.
12. earth leakage protective device according to claim 5 is characterized in that: said the 2nd Resistor-Capacitor Unit adopts the assembly of resistance or electric capacity or resistance and electric capacity.
13. earth leakage protective device according to claim 6 is characterized in that: said the 1st Resistor-Capacitor Unit adopts the assembly of resistance or electric capacity or resistance and electric capacity.
CN 201220108640 2012-03-21 2012-03-21 Leakage protector Expired - Lifetime CN202616744U (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103346532A (en) * 2013-07-11 2013-10-09 余姚市嘉荣电子电器有限公司 Electric leakage prevention plug circuit
CN103474955A (en) * 2013-09-27 2013-12-25 余姚市嘉荣电子电器有限公司 Earth leakage protection plug
CN103490378A (en) * 2013-09-03 2014-01-01 辽宁工程技术大学 Communication type selective electric leakage protection device
CN103490238A (en) * 2013-09-27 2014-01-01 余姚市嘉荣电子电器有限公司 Electric leakage protecting plug
CN104577977A (en) * 2014-12-26 2015-04-29 余姚市嘉荣电子电器有限公司 Voltage and current switchable type electric leakage protection device
CN105048216A (en) * 2015-07-07 2015-11-11 深圳市良辉科技有限公司 Earth leakage protection plug being capable of detecting fault current and fault voltage of ground lines

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103346532A (en) * 2013-07-11 2013-10-09 余姚市嘉荣电子电器有限公司 Electric leakage prevention plug circuit
CN103346532B (en) * 2013-07-11 2016-04-13 余姚市嘉荣电子电器有限公司 Electric leakage prevention plug circuit
CN103490378A (en) * 2013-09-03 2014-01-01 辽宁工程技术大学 Communication type selective electric leakage protection device
CN103474955A (en) * 2013-09-27 2013-12-25 余姚市嘉荣电子电器有限公司 Earth leakage protection plug
CN103490238A (en) * 2013-09-27 2014-01-01 余姚市嘉荣电子电器有限公司 Electric leakage protecting plug
CN103490238B (en) * 2013-09-27 2016-06-29 余姚市嘉荣电子电器有限公司 Leakage protecting plug
CN104577977A (en) * 2014-12-26 2015-04-29 余姚市嘉荣电子电器有限公司 Voltage and current switchable type electric leakage protection device
CN105048216A (en) * 2015-07-07 2015-11-11 深圳市良辉科技有限公司 Earth leakage protection plug being capable of detecting fault current and fault voltage of ground lines

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