CN208421116U - A kind of voltage induced formula protection against electric shock circuit and anti-electric shock apparatus - Google Patents
A kind of voltage induced formula protection against electric shock circuit and anti-electric shock apparatus Download PDFInfo
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- CN208421116U CN208421116U CN201821002233.5U CN201821002233U CN208421116U CN 208421116 U CN208421116 U CN 208421116U CN 201821002233 U CN201821002233 U CN 201821002233U CN 208421116 U CN208421116 U CN 208421116U
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Abstract
This application discloses a kind of voltage induced formula protection against electric shock circuit and anti-electric shock apparatus.The circuit includes: signal input terminal, is used for input voltage induction type electric signal;First filter circuit, for filtering out the first interference signal in voltage induced formula electric signal;Second filter circuit, for further filtering out the second interference signal;Amplifying circuit exports amplified tertiary voltage induction type electric signal to third filter circuit for carrying out signal enhanced processing to the second voltage induction type electric signal after filtering processing;Third filter circuit, for filtering out the third interference signal in tertiary voltage induction type electric signal, the 4th voltage induced formula electric signal of output to logic device;Logic device exports logic electric signal for obtaining logic electric signal according to the 4th voltage induced formula electric signal.By adopting the above technical scheme, due to realizing voltage acquisition function based on analog circuit, there is higher sensitivity, information processing rate is faster.
Description
Technical field
The invention relates to the technology of measurement electric variable more particularly to a kind of voltage induced formula protection against electric shock circuit and prevent
Electrocution devices.
Background technique
Field is monitored in protection against electric shock, there is through Current Mutual Inductance monitoring leakage electric current the risk to determine whether presence is got an electric shock, but
For the ground line etc. of some good device housings of ground connection, though there is leakage current, voltage is equal to big ground voltage (0V), does not have
Electric shock risk, monitoring and warning information are nonsensical.
Utility model content
The application provides a kind of voltage induced formula protection against electric shock circuit and anti-electric shock apparatus, can optimize traditional transformer measurement
Scheme.
In a first aspect, the embodiment of the present application provides a kind of voltage induced formula protection against electric shock circuit, comprising: signal input part
Son, the first filter circuit, the second filter circuit, amplifying circuit, third filter and logic device;
The signal input terminal is used for input voltage induction type electric signal, wherein the voltage induced formula electric signal is
Pass through the collected voltage signal of default test point of acquisition probe contact measured route;
First filter circuit is electrically connected with the signal input terminal, for filtering out the voltage induced formula electric signal
In the first interference signal;
Second filter circuit is electrically connected with the signal input terminal, for filtering out the voltage induced formula electric signal
In the second interference signal, wherein first filter circuit is in parallel with second filter circuit;
The amplifying circuit is electrically connected with second filter circuit, for the second voltage induction type after filtering processing
Electric signal carries out signal enhanced processing, exports amplified tertiary voltage induction type electric signal to third filter circuit;
The third filter circuit is electrically connected with logic device, for filtering out in the tertiary voltage induction type electric signal
Three interference signals export the 4th voltage induced formula electric signal after being filtered to logic device;
The logic device is patrolled described in output for obtaining logic electric signal according to the 4th voltage induced formula electric signal
Collect electric signal, wherein when the 4th voltage induced formula electric signal is high level, logic electric signal is low level.
Second aspect, the embodiment of the present application also provides a kind of voltage induced formula anti-electric shock apparatus, have such as above-mentioned first
Voltage induced formula protection against electric shock circuit described in aspect further includes sensor housing, shielded cable and acquisition probe;
The voltage induced formula protection against electric shock circuit is set in sensor shell body, the sensor housing using marine glue into
Row encapsulating;
The acquisition probe passes through the voltage induced formula protection against electric shock circuit connection in shielded cable and the sensor housing.
The embodiment of the present application provides a kind of voltage induced formula protection against electric shock circuit, including signal input terminal, the first filtered electrical
Road, the second filter circuit, amplifying circuit, third filter and logic device, the signal input terminal incude for input voltage
Formula electric signal, wherein the voltage induced formula electric signal is acquired by the default test point of acquisition probe contact measured route
The voltage signal arrived;It is filtered by filter circuit, and signal enhanced processing is carried out by amplifying circuit;Pass through logic device root
Logic electric signal is obtained according to filtering and amplified induction type electric signal, exports the logic electric signal, wherein if voltage induced
When formula electric signal is high level, then logic electric signal is low level, determines whether to leak electricity according to the value of logic electric signal
Situation.By adopting the above technical scheme, due to realizing voltage acquisition function based on analog circuit, conventional current mutual inductance detection leakage is solved
The defect of electric scheme has higher sensitivity, and information processing rate is faster.
Detailed description of the invention
Fig. 1 is a kind of structural schematic diagram for voltage induced formula protection against electric shock circuit that the embodiment of the present application one provides;
Fig. 2 is a kind of perspective view for voltage induced formula anti-electric shock apparatus that the embodiment of the present application two provides;
Fig. 3 is a kind of structural schematic diagram for voltage induced formula anti-electric shock apparatus that the embodiment of the present application two provides.
Specific embodiment
The application is described in further detail with reference to the accompanying drawings and examples.It is understood that this place is retouched
The specific embodiment stated is used only for explaining the application, rather than the restriction to the application.It also should be noted that in order to just
Part relevant to the application is illustrated only in description, attached drawing rather than entire infrastructure.
Embodiment one
Fig. 1 is a kind of structural schematic diagram for voltage induced formula protection against electric shock circuit that the embodiment of the present application one provides, such as Fig. 1 institute
Show, which includes:
Signal input terminal 1, the first filter circuit 2, the second filter circuit 3, amplifying circuit 4, third filter 5 and logic
Device 6;
The signal input terminal 1 is used for input voltage induction type electric signal, wherein the voltage induced formula electric signal
It is the collected voltage signal of default test point by acquisition probe contact measured route;
First filter circuit 2 is electrically connected with the signal input terminal 1, for filtering out the voltage induced formula telecommunications
The first interference signal in number;
Second filter circuit 3 is electrically connected with the signal input terminal 1, for filtering out the voltage induced formula telecommunications
The second interference signal in number, wherein first filter circuit 2 is in parallel with second filter circuit 3;
The amplifying circuit 4 is electrically connected with second filter circuit 3, for incuding to the second voltage after filtering processing
Formula electric signal carries out signal enhanced processing, exports amplified tertiary voltage induction type electric signal to third filter circuit 5;
The third filter circuit 5 is electrically connected with logic device 6, for filtering out in the tertiary voltage induction type electric signal
Third interference signal exports the 4th voltage induced formula electric signal after being filtered to logic device 6;
The logic device 6 is patrolled described in output for obtaining logic electric signal according to the 4th voltage induced formula electric signal
Collect electric signal, wherein when the 4th voltage induced formula electric signal is high level, logic electric signal is low level.
Optionally, first filter circuit 2 includes the 5th capacitor and first resistor, the 5th capacitor and described first
Resistor coupled in parallel, the 5th capacitor connect the signal input terminal with a common end of the first resistor, another is public
End ground connection altogether.
Optionally, second filter circuit 3 includes first capacitor, the 7th capacitor and second resistance, the first capacitor
In parallel with the second resistance, the first capacitor connect the signal input part with a common end of the second resistance
Son, another common end are connected and are grounded after the 7th capacitor.
Optionally, the amplifying circuit 4 includes concatenated 6th capacitor, first diode, the 5th resistance and the 6th resistance,
The cathode of the first diode connects the 6th capacitor, and the anode of the first diode connects the 6th resistance, institute
The base stage of the first triode of common end connection of the 5th resistance and the 6th resistance is stated, the other end of the 5th resistance connects electricity
Source, the emitter of first triode connect power supply, and the collector of first triode connects the third filter circuit
5.Wherein, the 6th capacitor C6=100pF, the model IN5819WS of first diode, the 5th resistance R5=47M Ω, the 6th is electric
Hinder R6=7.1M Ω.
Optionally, first triode is PNP type triode.
Optionally, the third filter circuit 5 includes 3rd resistor, the second capacitor, the 4th resistance and the 4th capacitor, described
Sub-circuit after 4th resistance is connected with the 4th capacitor is in parallel with second capacitor and 3rd resistor, the 3rd resistor and
One common end of two capacitors is connect with the collector of first triode, the 3rd resistor and the second capacitor another
The common end of common end grounding, the 4th resistance and the 4th capacitor connects the logic device 6.
Optionally, first group of input terminal of the logic device 6 is connect with the third filter circuit, and the of the logic device
One output end exports the controller of logic electric signal to sensor, is grounded after the tenth resistance of the first output end series connection, wherein
The sensor is for exporting leakage pre-alarm information.
Illustratively, it is assumed that there are drain conditions for route to be measured, are collected by signal input terminal by default test point
Voltage signal, and voltage signal is high level.As shown in Figure 1, what the voltage signal was made up of first resistor and the 5th capacitor
First filter circuit 2 is filtered, and filters out the first interference signal.Wherein, first resistor R1=44M Ω, the 5th capacitor C5
=33nF, thus, the frequency separation for the first interference signal that can be filtered out can be determined based on above-mentioned numerical value.In addition, using first
The second filter circuit 3 that capacitor, second resistance and the 7th capacitor are constituted is filtered again, filters out the second interference signal.Wherein,
First capacitor C1 is higfh-tension ceramics patch capacitor, and model 102K/2KV X7R, second resistance R2 are varistor, model
1812SH471KT-501 and the 7th capacitor C7=100pF, thus, it can determine that can filter out second is dry based on above-mentioned numerical value
The frequency separation for disturbing signal, the second voltage induction type electric signal after being filtered, wherein second voltage induction type telecommunications
Number be high level.To be applied with the electric signal contrary with power supply VCC at the both ends of the 6th capacitor C6, in turn, make first
Triode Q1 conducting, and high level (tertiary voltage induction type electric signal) is exported to third filter circuit 5.Third filter circuit 5
It is made of 3rd resistor R3, the second capacitor C2, the 4th resistance R4 and the 4th capacitor C4, wherein 3rd resistor R3=1.2M Ω, the
Two capacitor C2=0.1uF, the 4th resistance R4=200K Ω, the 4th capacitor C4=0.1uF, thus, it can be true based on above-mentioned numerical value
Surely the frequency separation for the third interference signal that can be filtered out obtains the 4th induction type electric signal, and exports to logic device 6.Logic device 6
It is the NAND gate IC device of four group of two channel input, when two inputs are high level, logic device 6 exports low level, and works as
When at least one in two inputs is low level, logic device exports high level.Since the 4th induction type electric signal is high level,
So output end UoutLogic electric signal (i.e. level) be flipped.Monolithic mechatronics in output end and sensor, if single
When the pin that piece machine is connect with logic device detects the logic electric signal of variation, it is possible to determine that voltage induced formula electric current occur, open
Dynamic comparator circuit (or ADC function) carries out signal comparison.If the voltage induced formula electric signal detected is higher than comparator circuit
Reference electrical signal, it is determined that leak electricity, export leakage pre-alarm information.Optionally, leakage pre-alarm can be believed by GPRS
Breath is sent to user mobile phone, realizes that high voltage induction answers early warning.
The embodiment of the present application provides a kind of voltage induced formula protection against electric shock circuit, including signal input terminal, the first filtered electrical
Road, the second filter circuit, amplifying circuit, third filter and logic device, the signal input terminal incude for input voltage
Formula electric signal, wherein the voltage induced formula electric signal is acquired by the default test point of acquisition probe contact measured route
The voltage signal arrived;It is filtered by filter circuit, and signal enhanced processing is carried out by amplifying circuit;Pass through logic device root
Logic electric signal is obtained according to filtering and amplified induction type electric signal, exports the logic electric signal, wherein if voltage induced
When formula electric signal is high level, then logic electric signal is low level, determines whether to leak electricity according to the value of logic electric signal
Situation.By adopting the above technical scheme, due to realizing voltage acquisition function based on analog circuit, conventional current mutual inductance detection leakage is solved
The defect of electric scheme has higher sensitivity, and information processing rate is faster.
In further embodiments, can also include working indicating, the working indicating include the 7th resistance,
9th resistance, the tenth resistance, eleventh resistor, third capacitor, the second triode, the 8th resistance and the second diode, for leading to
Cross the flashing indicating operating status of the second diode;
One end of 7th resistance connects the first input end of second group of input terminal of the logic device, and described second group
Second input terminal of input terminal connects first output end;
One end of 9th resistance is separately connected the second output terminal and third group input terminal of the logic device;
The other end of 7th resistance connects the other end of the 9th resistance, the 7th resistance and the 9th resistance
Common end series connection third capacitor and eleventh resistor, one end of eleventh resistor connect the third capacitor, the 11st electricity
The other end of resistance connects the base stage of the second triode;
The emitter of second triode is grounded, and the collector of second triode, which is connected, connects the after the 8th resistance
The anode of the cathode of two diodes, second triode connects power supply.
Optionally, second triode is NPN type triode.
Illustratively, in working indicating, third capacitor C3=0.1uF, the 7th resistance R7=510K Ω, the 9th electricity
Hinder R9=2M Ω, eleventh resistor R11=300R 1%, the 8th resistance R8=100R 1%, wherein pass through third capacitor and the
The value of 11 resistance can control the time of electric discharge, thus, the flashing of the second diode is controlled, voltage induced formula is used to indicate
Whether protection against electric shock circuit is in running order.
Fig. 2 is a kind of perspective view for voltage induced formula anti-electric shock apparatus that the embodiment of the present application one provides.As shown in Fig. 2,
A kind of voltage induced formula anti-electric shock apparatus, including sensor housing 10, shielded cable 30 and acquisition probe 20;
The voltage induced formula protection against electric shock circuit is set in sensor housing 10, and the sensor housing 10 utilizes waterproof
Glue is potted, wherein the structure that there is voltage induced formula protection against electric shock circuit above-described embodiment one to record;
The acquisition probe 20 passes through the voltage induced formula protection against electric shock electricity in shielded cable 30 and the sensor housing 10
Road connection.Wherein, shielded cable uses the earth shield line with shield effectiveness.
Illustratively, Fig. 3 is a kind of structural representation for voltage induced formula anti-electric shock apparatus that the embodiment of the present application two provides
Figure, as shown in figure 3, the voltage induced formula anti-electric shock apparatus acquisition probe uses integrated design, external aluminium flake and default detection
Point contact (can be connected by screw bolts two aluminium flakes, when aluminium flake is contacted and is grounded, by tightening the fixed aluminium flake of bolt and ground connection
Line), if there is drain conditions, acquisition probe, which can detecte, leaks electricity and passes through aluminium flake for voltage induced formula electric signal input voltage sense
The signal input terminal for answering formula protection against electric shock circuit realizes the detection acquisition of voltage.Optionally, D1=in the size of acquisition probe
20.2cm, D2=38cm and D3=6.2cm.In turn, signal acquisition and amplified signal are realized in the first triode Q1 conducting.Its
In, the size for adjusting the 6th resistance R6 can be realized the adjustment of voltage threshold, to realize the shielding and filtering of other voltage values
Interference signal.When voltage signal collected is after logic device U2, signal can be identified by single-chip microcontroller.Wherein, logic device
U2 realizes the digitized processing of the voltage induced formula electric signal.The controller (can be single-chip microcontroller) and logic device that sensor includes
Logical pin connect.When controller is received from the logic electric signal of logic device U2 variation, determine voltage currently occur
Induction type electric signal starts the ADC function of controller, is judged signal and handled.If voltage induced formula electric signal is higher than
Reference electrical signal then exports leakage pre-alarm information.
The present embodiment provides a kind of voltage induced formula anti-electric shock apparatus to be acquired using voltage induced formula protection against electric shock circuit
The acquisition process of voltage induced charge is realized at end, is retransmited the controller into the sensor connecting with acquisition probe, is realized
Application of the voltage induced formula circuit on anti-electric shock apparatus has parameter due to realizing voltage acquisition function using analog circuit
Adjustable advantage improves the sensitivity and stability of anti-electric shock apparatus, meanwhile, information processing rate faster, reduces
The power consumption of device.Meanwhile sensor housing is potted using marine glue, is used for circuit water-proof, is improved device itself
Safety.
Note that above are only the preferred embodiment and institute's application technology principle of the application.It will be appreciated by those skilled in the art that
The application is not limited to specific embodiment described here, be able to carry out for a person skilled in the art it is various it is apparent variation,
The protection scope readjusted and substituted without departing from the application.Therefore, although being carried out by above embodiments to the application
It is described in further detail, but the application is not limited only to above embodiments, in the case where not departing from the application design, also
It may include more other equivalent embodiments, and scope of the present application is determined by the scope of the appended claims.
Claims (10)
1. a kind of voltage induced formula protection against electric shock circuit characterized by comprising signal input terminal, the first filter circuit, second
Filter circuit, amplifying circuit, third filter and logic device;
The signal input terminal is used for input voltage induction type electric signal, wherein the voltage induced formula electric signal is to pass through
The collected voltage signal of default test point of acquisition probe contact measured route;
First filter circuit is electrically connected with the signal input terminal, for filtering out in the voltage induced formula electric signal
First interference signal;
Second filter circuit is electrically connected with the signal input terminal, for filtering out in the voltage induced formula electric signal
Second interference signal, wherein first filter circuit is in parallel with second filter circuit;
The amplifying circuit is electrically connected with second filter circuit, for the second voltage induction type telecommunications after filtering processing
Number carry out signal enhanced processing, export amplified tertiary voltage induction type electric signal to third filter circuit;
The third filter circuit is electrically connected with logic device, dry for filtering out the third in the tertiary voltage induction type electric signal
Signal is disturbed, the 4th voltage induced formula electric signal after output filtering processing to logic device;
The logic device exports the logic electricity for obtaining logic electric signal according to the 4th voltage induced formula electric signal
Signal, wherein when the 4th voltage induced formula electric signal is high level, logic electric signal is low level.
2. voltage induced formula protection against electric shock circuit according to claim 1, which is characterized in that first filter circuit includes
5th capacitor and first resistor, the 5th capacitor is in parallel with the first resistor, the 5th capacitor and the first resistor
A common end connect the signal input terminal, another common end grounding.
3. voltage induced formula protection against electric shock circuit according to claim 1, which is characterized in that second filter circuit includes
First capacitor, the 7th capacitor and second resistance, the first capacitor is in parallel with the second resistance, the first capacitor with it is described
One common end of second resistance connects the signal input terminal, is grounded after the 7th capacitor of another common end series connection.
4. voltage induced formula protection against electric shock circuit according to claim 1, which is characterized in that the amplifying circuit includes series connection
The 6th capacitor, first diode, the 5th resistance and the 6th resistance, the first diode cathode connection it is described 6th electricity
Hold, the anode of the first diode connects the 6th resistance, the common end connection of the 5th resistance and the 6th resistance the
The base stage of one triode, the other end of the 5th resistance connect power supply, and the emitter of first triode connects power supply, institute
The collector for stating the first triode connects the third filter circuit.
5. voltage induced formula protection against electric shock circuit according to claim 4, which is characterized in that first triode is PNP
Type triode.
6. voltage induced formula protection against electric shock circuit according to claim 4 or 5, which is characterized in that the third filter circuit
Including 3rd resistor, the second capacitor, the 4th resistance and the 4th capacitor, the 4th resistance connect with the 4th capacitor after sub-circuit
It is in parallel with second capacitor and 3rd resistor, the common end and the one or three pole of the 3rd resistor and the second capacitor
The collector of pipe connects, another common end grounding of the 3rd resistor and the second capacitor, the 4th resistance and the 4th electricity
The common end of appearance connects the logic device.
7. voltage induced formula protection against electric shock circuit according to claim 1, which is characterized in that first group of the logic device is defeated
Enter end to connect with the third filter circuit, the first output end of the logic device exports the control of logic electric signal to sensor
Device, first output end are connected and are grounded after the tenth resistance, wherein the sensor is for exporting leakage pre-alarm information.
8. voltage induced formula protection against electric shock circuit according to claim 7, which is characterized in that it further include working indicating,
The working indicating includes the 7th resistance, the 9th resistance, the tenth resistance, eleventh resistor, third capacitor, the two or three pole
Pipe, the 8th resistance and the second diode, for passing through the flashing indicating operating status of the second diode;
One end of 7th resistance connects the first input end of second group of input terminal of the logic device, second group of input
Second input terminal at end connects first output end;
One end of 9th resistance is separately connected the second output terminal and third group input terminal of the logic device;
The other end of 7th resistance connects the other end of the 9th resistance, and the 7th resistance is public with the 9th resistance
One end of end series connection third capacitor and eleventh resistor, eleventh resistor connects the third capacitor, the eleventh resistor
The other end connects the base stage of the second triode;
The emitter of second triode is grounded, and connects the two or two after collector the 8th resistance of series connection of second triode
The anode of the cathode of pole pipe, second triode connects power supply.
9. voltage induced formula protection against electric shock circuit according to claim 8, which is characterized in that second triode is NPN
Type triode.
10. a kind of voltage induced formula anti-electric shock apparatus, which is characterized in that have voltage described in any one of claims 1 to 9
Induction type protection against electric shock circuit further includes sensor housing, shielded cable and acquisition probe;
The voltage induced formula protection against electric shock circuit is set in sensor shell body, and the sensor housing is filled using marine glue
Envelope;
The acquisition probe passes through the voltage induced formula protection against electric shock circuit connection in shielded cable and the sensor housing.
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CN201821002233.5U CN208421116U (en) | 2018-06-27 | 2018-06-27 | A kind of voltage induced formula protection against electric shock circuit and anti-electric shock apparatus |
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CN201821002233.5U CN208421116U (en) | 2018-06-27 | 2018-06-27 | A kind of voltage induced formula protection against electric shock circuit and anti-electric shock apparatus |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108594065A (en) * | 2018-06-27 | 2018-09-28 | 广州华铭电力科技有限公司 | A kind of voltage induced formula protection against electric shock circuit and anti-electric shock apparatus |
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2018
- 2018-06-27 CN CN201821002233.5U patent/CN208421116U/en active Active
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108594065A (en) * | 2018-06-27 | 2018-09-28 | 广州华铭电力科技有限公司 | A kind of voltage induced formula protection against electric shock circuit and anti-electric shock apparatus |
CN108594065B (en) * | 2018-06-27 | 2024-03-05 | 广州华铭电力科技有限公司 | Voltage induction type electric shock prevention circuit and electric shock prevention device |
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