CN203490312U - Aging detection circuit of grounding wire of electric equipment - Google Patents
Aging detection circuit of grounding wire of electric equipment Download PDFInfo
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- CN203490312U CN203490312U CN201320628083.XU CN201320628083U CN203490312U CN 203490312 U CN203490312 U CN 203490312U CN 201320628083 U CN201320628083 U CN 201320628083U CN 203490312 U CN203490312 U CN 203490312U
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- 230000032683 aging Effects 0.000 title abstract description 18
- 238000001514 detection method Methods 0.000 title abstract description 9
- 238000012544 monitoring process Methods 0.000 claims abstract description 25
- 238000006243 chemical reaction Methods 0.000 claims description 25
- 239000003990 capacitor Substances 0.000 claims description 19
- 238000012360 testing method Methods 0.000 claims description 19
- 239000013078 crystal Substances 0.000 claims description 5
- 238000011084 recovery Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 description 8
- 230000007774 longterm Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000000007 visual effect Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000002354 daily effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000003203 everyday effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000011897 real-time detection Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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Abstract
The utility model discloses an aging detection circuit of a grounding wire of electric equipment. The aging detection circuit comprises a voltage acquisition circuit, a power management circuit and a single-chip-microcomputer monitoring circuit, wherein the voltage acquisition circuit is connected with the single-chip-microcomputer monitoring circuit; and the power management circuit is connected with the voltage acquisition circuit and the single-chip-microcomputer monitoring circuit. The aging detection circuit disclosed by the utility model has the advantages that the aging detection circuit adopts the single-chip-microcomputer as a control center, and is used for detecting electric equipment, especially for detecting the aging degree of the grounding wire of the electric equipment with need of long-time use (for example, more than 5 years) or severer working conditions (such as occasions with certain corrosivity); after the grounding wire is aged, the resistance is increased; according to the principle, a certain current is input into one end of the grounding wire, the voltage of the input end of the grounding wire is acquired by an amplifying circuit, the voltage value increases along with increase of the aging degree of the grounding wire, and when the voltage value is larger than a certain threshold, the grounding wire cannot be used.
Description
Technical field
The utility model relates to testing circuit, relates in particular to a kind of electrical equipment grounding line burn-in test circuit.
Background technology
For guaranteeing the inherently safe of electrical equipment and operating personnel's safety, the shell of electrical equipment needs grounding conventionally, and high voltage electric equipment especially, if occur imperfect earth, the static that its shell gathers will reach several ten thousand even tens0000 volts, bring great threat to staff's personal safety.The aging of electrical equipment grounding line is comprised of two parts, a part be joint because long term exposure is oxidized gradually in air, cause resistance to increase; Another part is that the oxidation of wire itself causes resistance to increase, and wherein take the former as main.When have large electric current by being oxidized position time, this position temperature will sharply increase, and likely cause fire when situation is serious, cause a serious accident.Because the aging of ground wire is generally a long-term process, thus easily out in the cold.And for being operated in field (as intelligent grid Centralized Controller etc.) or thering is the electrical equipment under corrosive gas environment, more easily occur that equipment ground is bad.
Judgement for electrical equipment grounding characteristic at present adopts three kinds of methods conventionally: after staff's field observation, rule of thumb judge; Specification according to ground wire, regularly replaces; Adopt earth resistance tester in-site measurement.These three kinds of methods have certain deficiency, and a kind of method depends on people's experience and visual sense, the most easily occur that judgement is inaccurate; In second method, the specification of circuit has certain test condition conventionally, for installation environment and the inconsistent occasion of test condition, inapplicable; The third method needs staff to carry resistance meter to carry out periodic measurement, and the common power consumption of tester is higher, thereby is not suitable for online detection.Based on above situation, develop a kind of microminiaturization, low-power consumption, it is very practical also necessary that checkout equipment that can long-term operation carries out to the ground wire of electrical equipment that ageing state detects.
Utility model content
Technical matters to be solved of the present utility model be to provide a kind of microminiaturization, low-power consumption, checkout equipment that can long-term operation carries out the testing circuit of ageing state detection to the ground wire of electrical equipment.
The utility model solves the problems of the technologies described above by the following technical solutions: a kind of electrical equipment grounding line burn-in test circuit, comprise voltage collection circuit, electric power management circuit, microcomputer monitoring circuit, voltage collection circuit is connected with microcomputer monitoring circuit, and electric power management circuit is connected with microcomputer monitoring circuit with voltage collection circuit respectively.
Concrete, described voltage collection circuit comprises operational amplifier U1, U2,12V electric battery V1, resistance R 1～R5, diode D1～D4, ground wire Rt to be measured, 1 pin of operational amplifier U1 is connected with 8 pin by resistance R 3, and 2 pin of operational amplifier U1 connect one end of R1 and the anode of diode D1, after the other end of resistance R 1 is connected with one end of resistance R 2, be connected with the 12V output terminal of electric power management circuit, 3 pin of another termination operational amplifier U1 of resistance R 2 and the anode of diode D3, the negative electrode of diode D3 is connected with the anode of diode D4, the plus earth of diode D4, the negative electrode of diode D1 is connected with the anode of diode D2, the negative electrode of diode D2 is connected to the junction of ground wire Rt to be measured and electrical equipment, the other end ground connection of ground wire Rt to be measured, diode D1～D4 is the high-voltage high-speed recovery diode that model is identical, ground connection after 4 pin of operational amplifier U1 are connected with 5 pin, 7 pin of operational amplifier U1 are connected with the 3.3V output terminal of electric power management circuit, 6 pin of operational amplifier U1 are connected with 4 pin of U2 by resistance R 4, 4 pin of operational amplifier U2 are connected with 1 pin of operational amplifier U2 by resistance R 5, 1 pin of operational amplifier U2 is connected with microcomputer monitoring circuit, ground connection after 2 pin of operational amplifier U2 are connected with 3 pin, 5 pin of operational amplifier U2 are connected with the 3.3V output terminal of electric power management circuit.
Concrete, described microcomputer monitoring circuit comprises single-chip microcomputer U4, resistance R 10～R13, capacitor C 4, crystal oscillator G1, loudspeaker LS1, triode T2, 1 pin of single-chip microcomputer U4 is connected with the 3.3V output terminal of electric power management circuit, and by capacitor C 4 ground connection, 5 pin of single-chip microcomputer U4 are connected with electric power management circuit with voltage collection circuit respectively with 6 pin, 26 pin of single-chip microcomputer U4 are connected with its 27 pin by crystal oscillator G1, the 28 pin ground connection of single-chip microcomputer U4, 17 pin of single-chip microcomputer U4 are connected with electric power management circuit 3.3V output terminal by resistance R 13, and be connected with the anode of light emitting diode D5, the plus earth of diode D5, 14 pin of single-chip microcomputer U4 are connected with electric power management circuit 3.3V output terminal by resistance R 12, and be connected with the base stage of triode T2 by resistance R 10, the grounded emitter of triode T2, the collector of triode T2 connects one end of loudspeaker LS1, the other end of loudspeaker LS1 is connected with the 12V output terminal of electric power management circuit by resistance R 11.
Concrete, described electric power management circuit comprises power conversion chip U3, electric battery V1, resistance R 6～R9, capacitor C 1～C3, triode T1, inductance L 1, ground connection after 1 pin of power conversion chip U3 is connected with 4 pin, after being connected with 3 pin, pass through on 2 pin of power conversion chip U3 capacitor C 2 ground connection, connect the positive pole of capacitor C 1 simultaneously, the minus earth of capacitor C 1, the positive pole of capacitor C 1 is connected with the positive pole of electric battery V1, the minus earth of electric battery V1, the positive pole of electric battery V1 connects the collector of triode T1, the transmitting of triode T1 is 12V output terminal very, be connected with microcomputer monitoring circuit with voltage collection circuit respectively, the base stage of triode T1 is connected with single chip machine controlling circuit by resistance R 6, 5 pin of power conversion chip U3 are by resistance R 9 ground connection, 6 pin of power conversion chip U3 are connected with 8 pin of power conversion chip U3 by resistance R 7, 7 pin of power conversion chip U3 are connected with 6 pin of power conversion chip U3 by inductance L 1, 6 pin of power conversion chip U3 are connected with 5 pin of power conversion chip U3 by resistance R 8, 6 pin of power conversion chip U3 are by capacitor C 3 ground connection, 6 pin of power conversion chip U3 are 3.3V voltage output end, be connected with microcomputer monitoring circuit with voltage collection circuit respectively.
The beneficial effect the utlity model has is:
1, testing circuit is low in energy consumption, is applicable to need the long-term comparatively detection of the ground wire degree of aging of the electrical equipment of severe (as having certain corrosive occasion) of (as more than 5 years) or condition of work of using.
2, testing circuit is quick on the draw, fast, and simple in structure, is applicable to being arranged in visual plant being used as real-time detection, also can make hand-held checkout equipment for daily operation.
3, can effectively detect the degree of aging of ground wire, and record ageing process, for varying environment, select ground wire and other wires of different brackets data supporting is provided.
4, when ground wire is aged to a certain degree, testing circuit reports to the police, and the equipment that prevents is because of the imperfect earth even accident that breaks down.
Accompanying drawing explanation
Fig. 1 is general structure block diagram of the present utility model.
Fig. 2 is voltage collection circuit figure of the present utility model.
Fig. 3 is electric power management circuit figure of the present utility model.
Fig. 4 is microcomputer monitoring circuit diagram of the present utility model.
Embodiment
Below in conjunction with accompanying drawing, the utility model is described in detail.
Fig. 1 is the utility model general structure block diagram.Comprise voltage collection circuit, electric power management circuit, microcomputer monitoring circuit, voltage collection circuit is connected with microcomputer monitoring circuit, and electric power management circuit is connected with microcomputer monitoring circuit with voltage collection circuit respectively.
Fig. 2 is voltage collection circuit figure of the present utility model.U1 and U2 are operational amplifiers, and in one example, U1 is INA333, and U2 is OPA333.1 pin of U1 is connected with 8 pin by resistance R 3, and 2 pin of U1 connect one end of R1 and the anode of D1; After the other end of R1 is connected with one end of R2, be connected with the 12V output terminal of electric power management circuit; 3 pin of another termination U1 of R2 and the anode of D3.The negative electrode of D3 is connected with the anode of D4, the plus earth of D4.The negative electrode of D1 is connected with the anode of D2, and the negative electrode of D2 is connected to the junction of tested ground wire and electrical equipment, the other end ground connection of tested ground wire.D1～D4 is the high-voltage high-speed recovery diode that model is identical, and D1～D4 is HER108 in one example.Ground connection after 4 pin of U1 are connected with 5 pin, 7 pin of U1 are connected with the 3.3V output terminal of electric power management circuit.6 pin of U1 are connected with 4 pin of U2 by resistance R 4, and 4 pin of U2 are connected with 1 pin of U2 by resistance R 5, and 1 pin of U2 is connected with microcomputer monitoring circuit.Ground connection after 2 pin of U2 are connected with 3 pin, 5 pin of U2 are connected with the 3.3V output terminal of electric power management circuit.
Fig. 3 is electric power management circuit figure of the present utility model.U3 is power conversion chip, and in one example, U3 is TPS62170.Ground connection after 1 pin of U3 is connected with 4 pin by capacitor C 2 ground connection, connects the positive pole of C1, the minus earth of C1 after 2 pin of U3 are connected with 3 pin simultaneously.The positive pole of C1 is connected with the positive pole of electric battery V1, the minus earth of V1.The positive pole of V1 connects the collector of triode T1, and the transmitting of T1 is 12V output terminal very, is connected respectively with voltage collection circuit with microcomputer monitoring circuit; The base stage of T1 is connected with single chip machine controlling circuit by resistance R 6.5 pin of U3 are by resistance R 9 ground connection, and 6 pin of U3 are connected with 8 pin of U3 by resistance R 7; 7 pin of U3 are connected with 6 pin of U3 by inductance L 1, and 6 pin of U3 are connected with 5 pin of U3 by resistance R 8, and 6 pin of U3 are by capacitor C 3 ground connection, and 6 pin of U3 are 3.3V voltage output end, are connected respectively with voltage collection circuit with microcomputer monitoring circuit.
Fig. 4 is microcomputer monitoring circuit diagram of the present utility model.U4 is single-chip microcomputer, and U4 is MSP430G2553 in one example.1 pin of U4 is connected with the 3.3V output terminal of electric power management circuit, and by capacitor C 4 ground connection; 5 pin of U4 are connected with electric power management circuit with voltage collection circuit respectively with 6 pin.26 pin of U4 are connected with its 27 pin by crystal oscillator G1, the 28 pin ground connection of U4.17 pin of U4 are connected with electric power management circuit 3.3V output terminal by resistance R 13, and are connected with the anode of light emitting diode D5, the plus earth of D5.14 pin of U4 are connected with electric power management circuit 3.3V output terminal by resistance R 12, and are connected with the base stage of triode T2 by resistance R 10.The grounded emitter of T2, the collector of T2 connects one end of loudspeaker LS1, and the other end of LS1 is connected with the 12V output terminal of electric power management circuit by resistance R 11.
The course of work of the present utility model is as follows:
In voltage collection circuit, the negative electrode of D2 is the input end of this ground wire burn-in test circuit, and this port is connected to the junction of ground wire and electrical equipment.When voltage collection circuit is started working, because D1～D4 model is identical, thereby ground connection is when normal, and 2 pin of U1 are consistent with the voltage of 3 pin inputs, and the voltage of 5 pin that 1 pin of U2 outputs to single-chip microcomputer U4 is very little.When ground wire is aging, the resistance of ground wire increases, voltage difference between 2 pin of U1 and 3 pin of U1 increases, this voltage difference is after U1 and U2 amplification, the voltage that is input to 5 pin of single-chip microcomputer U4 increases, and this voltage increases along with the increase of ground wire degree of aging, by judging this magnitude of voltage, can judge the degree of aging of circuit.User can pass through pre-stage test, and alarm threshold value is set, and, when the voltage detecting arrives this threshold value, Single-chip Controlling loudspeaker LS1 and light emitting diode D5 work, produce sound and light alarm.
Because the ageing process of circuit is very slow, if thereby circuit is checked always, can cause battery electric quantity waste.Thereby the 12V voltage of the voltage collection circuit of this ground wire burn-in test circuit is realized by resistance R 6 control triode T1 by single-chip microcomputer.User can set and detect frequency and detection time in single-chip microcomputer, as detected once every day, detects three minutes at every turn.While needing to detect, 6 pin of single-chip microcomputer U4 set high level, T1 conducting, thus make voltage collection circuit work.While not detecting, 6 pin of U4 set low level, and voltage collection circuit is not worked, thereby can play the effect of power saving.Chip used in this testing circuit is low-power chip, and object is to extend the serviceable life of battery and the activity duration of whole testing circuit.
The foregoing is only the preferred embodiment that the utility model is created; in order to limit the utility model, do not create; any modification of doing within all spirit of creating at the utility model and principle, be equal to and replace and improvement etc., within all should being included in the protection domain that the utility model creates.
Claims (4)
1. an electrical equipment grounding line burn-in test circuit, it is characterized in that: comprise voltage collection circuit, electric power management circuit, microcomputer monitoring circuit, voltage collection circuit is connected with microcomputer monitoring circuit, and electric power management circuit is connected with microcomputer monitoring circuit with voltage collection circuit respectively.
2. a kind of electrical equipment grounding line burn-in test circuit according to claim 1, it is characterized in that: described voltage collection circuit comprises operational amplifier U1, U2,12V electric battery V1, resistance R 1～R5, diode D1～D4, ground wire Rt to be measured, 1 pin of operational amplifier U1 is connected with 8 pin by resistance R 3, and 2 pin of operational amplifier U1 connect one end of R1 and the anode of diode D1, after the other end of resistance R 1 is connected with one end of resistance R 2, be connected with the 12V output terminal of electric power management circuit, 3 pin of another termination operational amplifier U1 of resistance R 2 and the anode of diode D3, the negative electrode of diode D3 is connected with the anode of diode D4, the plus earth of diode D4, the negative electrode of diode D1 is connected with the anode of diode D2, the negative electrode of diode D2 is connected to the junction of ground wire Rt to be measured and electrical equipment, the other end ground connection of ground wire Rt to be measured, diode D1～D4 is the high-voltage high-speed recovery diode that model is identical, ground connection after 4 pin of operational amplifier U1 are connected with 5 pin, 7 pin of operational amplifier U1 are connected with the 3.3V output terminal of electric power management circuit, 6 pin of operational amplifier U1 are connected with 4 pin of U2 by resistance R 4, 4 pin of operational amplifier U2 are connected with 1 pin of operational amplifier U2 by resistance R 5, 1 pin of operational amplifier U2 is connected with microcomputer monitoring circuit, ground connection after 2 pin of operational amplifier U2 are connected with 3 pin, 5 pin of operational amplifier U2 are connected with the 3.3V output terminal of electric power management circuit.
3. a kind of electrical equipment grounding line burn-in test circuit according to claim 1, it is characterized in that: described microcomputer monitoring circuit comprises single-chip microcomputer U4, resistance R 10～R13, capacitor C 4, crystal oscillator G1, loudspeaker LS1, triode T2, 1 pin of single-chip microcomputer U4 is connected with the 3.3V output terminal of electric power management circuit, and by capacitor C 4 ground connection, 5 pin of single-chip microcomputer U4 are connected with electric power management circuit with voltage collection circuit respectively with 6 pin, 26 pin of single-chip microcomputer U4 are connected with its 27 pin by crystal oscillator G1, the 28 pin ground connection of single-chip microcomputer U4, 17 pin of single-chip microcomputer U4 are connected with electric power management circuit 3.3V output terminal by resistance R 13, and be connected with the anode of light emitting diode D5, the plus earth of diode D5, 14 pin of single-chip microcomputer U4 are connected with electric power management circuit 3.3V output terminal by resistance R 12, and be connected with the base stage of triode T2 by resistance R 10, the grounded emitter of triode T2, the collector of triode T2 connects one end of loudspeaker LS1, the other end of loudspeaker LS1 is connected with the 12V output terminal of electric power management circuit by resistance R 11.
4. according to a kind of electrical equipment grounding line burn-in test circuit described in claims 1 to 3 any one, it is characterized in that: described electric power management circuit comprises power conversion chip U3, electric battery V1, resistance R 6～R9, capacitor C 1～C3, triode T1, inductance L 1, ground connection after 1 pin of power conversion chip U3 is connected with 4 pin, after being connected with 3 pin, pass through on 2 pin of power conversion chip U3 capacitor C 2 ground connection, connect the positive pole of capacitor C 1 simultaneously, the minus earth of capacitor C 1, the positive pole of capacitor C 1 is connected with the positive pole of electric battery V1, the minus earth of electric battery V1, the positive pole of electric battery V1 connects the collector of triode T1, the transmitting of triode T1 is 12V output terminal very, be connected with microcomputer monitoring circuit with voltage collection circuit respectively, the base stage of triode T1 is connected with single chip machine controlling circuit by resistance R 6, 5 pin of power conversion chip U3 are by resistance R 9 ground connection, 6 pin of power conversion chip U3 are connected with 8 pin of power conversion chip U3 by resistance R 7, 7 pin of power conversion chip U3 are connected with 6 pin of power conversion chip U3 by inductance L 1, 6 pin of power conversion chip U3 are connected with 5 pin of power conversion chip U3 by resistance R 8, 6 pin of power conversion chip U3 are by capacitor C 3 ground connection, 6 pin of power conversion chip U3 are 3.3V voltage output end, be connected with microcomputer monitoring circuit with voltage collection circuit respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320628083.XU CN203490312U (en) | 2013-10-11 | 2013-10-11 | Aging detection circuit of grounding wire of electric equipment |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320628083.XU CN203490312U (en) | 2013-10-11 | 2013-10-11 | Aging detection circuit of grounding wire of electric equipment |
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| CN203490312U true CN203490312U (en) | 2014-03-19 |
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| CN201320628083.XU Expired - Lifetime CN203490312U (en) | 2013-10-11 | 2013-10-11 | Aging detection circuit of grounding wire of electric equipment |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103472345A (en) * | 2013-10-11 | 2013-12-25 | 中国电子科技集团公司第三十八研究所 | Aging detection circuit of grounding wire of electric equipment |
| CN112217421A (en) * | 2020-09-01 | 2021-01-12 | 杭州阔博科技有限公司 | Circuit, method and controller for preventing electric vehicle from being started by mistake and electric vehicle |
-
2013
- 2013-10-11 CN CN201320628083.XU patent/CN203490312U/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103472345A (en) * | 2013-10-11 | 2013-12-25 | 中国电子科技集团公司第三十八研究所 | Aging detection circuit of grounding wire of electric equipment |
| CN103472345B (en) * | 2013-10-11 | 2015-11-18 | 中国电子科技集团公司第三十八研究所 | A kind of electrical equipment grounding line burn-in test circuit |
| CN112217421A (en) * | 2020-09-01 | 2021-01-12 | 杭州阔博科技有限公司 | Circuit, method and controller for preventing electric vehicle from being started by mistake and electric vehicle |
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Granted publication date: 20140319 |