CN202903945U - Direct-current system line grounding fault alarm apparatus - Google Patents
Direct-current system line grounding fault alarm apparatus Download PDFInfo
- Publication number
- CN202903945U CN202903945U CN 201220628847 CN201220628847U CN202903945U CN 202903945 U CN202903945 U CN 202903945U CN 201220628847 CN201220628847 CN 201220628847 CN 201220628847 U CN201220628847 U CN 201220628847U CN 202903945 U CN202903945 U CN 202903945U
- Authority
- CN
- China
- Prior art keywords
- ground
- earth
- direct
- grounding fault
- grounding
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000001514 detection method Methods 0.000 claims abstract description 10
- 238000006243 chemical reaction Methods 0.000 claims abstract description 7
- 238000012806 monitoring device Methods 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 7
- 238000004364 calculation method Methods 0.000 claims description 3
- 238000004088 simulation Methods 0.000 claims description 2
- 238000005070 sampling Methods 0.000 description 3
- 230000005611 electricity Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
Landscapes
- Locating Faults (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
A direct-current system line grounding fault alarm apparatus is formed by a grounding fault detection portion, an analog-to-digital conversion portion, a single chip microcomputer operation processing portion and a display alarm portion. The apparatus is characterized in that the grounding fault detection portion is comprised; a monitoring device leads out three terminals which are connected to a positive wire, a negative wire and the ground of a monitored direct-current power supply; four resistors of an R1, an R2, an R3 and an R4 are connected in series, wherein the R1, the R2, the R3 and the R4 satisfy the following formulas: R1=R4 and R2=R3; a connection point between the R2 and the R3 is connected to the ground and simultaneously the point is connected with the analog ground and the digital ground on a circuit board. A grounding fault signal detection circuit in the utility model is simple, practical and reliable. A direct current voltage value and grounding frequency recording display function is possessed. An dynamic grounding recording function is possessed.
Description
Affiliated technical field
The utility model belongs to electricity field, be a kind of can be in the situation that the online main track of DC control supply and the detection alarm device whether negative wire exists earth point of detecting.
Technical background
On-the-spot in Industry Control, a lot of control system adopt the mode of DC power supply, in the on-the-spot Programmable Logic Controller that extensively adopts of Industry Control and the distributed peripheral control system that consists of thereof, often adopt direct current as the power supply of PLC input, output module and load thereof.The circuit of this system has and has a very wide distribution, and characteristics that circuit is many, and the cable of the power supply of some equipment, measurement, control also must move such as the hydraulic jack of solenoid control etc., in use are easy to cause circuit wearing and tearing broken skin and ground connection.Independent main track or negative wire ground connection can't affect the normal operation of system, if but on main track and negative wire, there is simultaneously earth point, will form short trouble, cause the protection switch tripping operation and send electricity not go up.Because circuit has a very wide distribution, searching earth point often needs to spend long time, thereby causes the long-time interruption of producing.
The utility model content
The utility model aims to provide a kind of straight-flow system line-to-ground fault alarm, can go out DC control supply and whether have earth point by on-line monitoring, comprises the hard earth fault of system and the short-time grounding fault that circuit occured in moving process.Have earth point or earth fault once occured in case device detects system, device will be recorded, and sends simultaneously chimes of doom alert device maintainer and in time processes, thereby avoid main track and negative wire simultaneously ground connection and the generation of the short trouble that causes.
The technical scheme of utility model: straight-flow system line-to-ground fault alarm, circuit partly is comprised of Earth Fault Detection part, analog to digital conversion part, single-chip microcomputer calculation process part, display alarm.It is characterized in that circuit is by the Earth Fault Detection part: monitoring device is drawn three terminals, is connected respectively to main track, negative wire and the earth of monitored direct supply.R1, R2, R3, four resistance of R4 are connected in series, R1=R4 wherein, R2=R3, and the tie point between R2, the R3 linked to each other with the earth, simultaneously this also with circuit board on simulation ground with digitally link to each other.
R2 is voltage sampling resistor, in order that take out the foundation that the voltage signal of circuit-under-test is judged as earth fault, also makes the voltage signal of this sampling within the input voltage range of analog-to-digital conversion module simultaneously.
The principle of earth fault input: suppose that DC voltage is Ud, if there are not earth point in main track and negative wire, voltage sum on resistance R 1 and the R2 (is subjected to the over the ground impact of distributed capacitance of positive negative wire about Ud/2, deviation to some extent), the voltage sum on R3 and the R4 is also about Ud/2.If there is earth point in main track, then the current potential of main track equates with earth potential, and the voltage sum on R1 and the R2 is about 0V so, and the voltage sum on R3 and the R4 is Ud; In like manner, if negative wire ground connection, the voltage sum on R1 and the R2 is about Ud, and the voltage sum on R3 and the R4 is about 0V.Can find out from above analysis, no matter main track ground connection or negative wire ground connection all will cause the variation of voltage on the resistance R 2, by detecting the variation of resistance R 2 both end voltage, just can judge whether straight-flow system exists earth point.
The upper voltage signal of R2 is sent to input end VIN+ and the VIN-of analog-to-digital conversion module U1, the negative terminal that analog quantity earth terminal A GND, digital quantity earth terminal D GND on the analog-to-digital conversion module and VIN-are connected to the device power supply, be sent to the P2 mouth of single-chip microcomputer U2 from the digital quantity signal of DB0 ~ DB7 output, the P0 mouth of single-chip microcomputer is connected to the section route selection of group of four figures pipe, and P1.0 ~ P1.3 is connected to the position route selection of group of four figures pipe.
Advantage of the present utility model: 1. the earth fault signal deteching circuit is simple, practical and reliable; 2. has dc voltage value and ground connection number of times record Presentation Function; 3. has dynamic ground connection writing function.For some removal cable, earth-free when static, the earth fault in short-term that in moving process, but may occur, this instrument also can get off this process record, and the maintainer can have access to the ground connection number of times and analyze judgement.
Description of drawings
Fig. 1 is the utility model way circuit figure.Fig. 2 is Earth Fault Detection partial circuit figure.
Among the figure: R1, R2, R3, R4 are the series connection divider resistance, and R1=R4, R2=R3, the mid point that R2 is connected with R3 link to each other with the earth, and wherein R2 is sample resistance.
Integrated package U1 is analog-to-digital conversion module, is used for the voltage analog signal of the upper sampling of R2 is converted to digital quantity signal.
Integrated package U2 is single-chip microcomputer, is used for the voltage signal calculation process of coming taking a sample.
U3 is group of four figures pipe, is used for showing magnitude of voltage and ground connection number of times.
SW0 is the switch of group of four figures pipe displaying contents.
Q1 is a positive-negative-positive triode, plays amplification, for hummer BUZ work provides enough electric currents.
Embodiment
Embodiment below in conjunction with accompanying drawing further specifies content of the present utility model.
Such as figure as show, draw three connection terminals at the circuit board that completes, be respectively the main track terminals of drawing on the R1, the negative wire terminals of drawing from R4, the ground wire terminals that the mid point that is connected with R3 from R2 is drawn.
During use, the main track terminals that fault is drawn are connected to the positive pole of institute's supervision direct supply, and the negative wire terminals are connected to the negative pole of power supply, and the ground wire terminals link to each other with the earth.After wiring is errorless, serve direct supply, straight-flow system line-to-ground detection alarm instrument is just started working.By switch transition switch SW 0, on 4 charactrons, can check magnitude of voltage and the earth fault number of times record of direct supply.The maintainer is when carrying out spot check to system, if find buzzer warning, then line-to-ground fault occured illustrative system now or once.So just remind the maintainer in time this earth fault to be got rid of, avoid the generation of main track and negative wire simultaneous ground fault.
Claims (1)
1. straight-flow system line-to-ground fault alarm, partly formed by Earth Fault Detection part, analog to digital conversion part, single-chip microcomputer calculation process part, display alarm, it is characterized in that the Earth Fault Detection part: monitoring device is drawn three terminals, be connected respectively to main track, negative wire and the earth of monitored direct supply, R1, R2, R3, four resistance of R4 are connected in series, R1=R4 wherein, R2=R3, and the tie point between R2, the R3 linked to each other with the earth, simultaneously this also with circuit board on simulation ground with digitally link to each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220628847 CN202903945U (en) | 2012-11-26 | 2012-11-26 | Direct-current system line grounding fault alarm apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220628847 CN202903945U (en) | 2012-11-26 | 2012-11-26 | Direct-current system line grounding fault alarm apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202903945U true CN202903945U (en) | 2013-04-24 |
Family
ID=48124601
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220628847 Expired - Lifetime CN202903945U (en) | 2012-11-26 | 2012-11-26 | Direct-current system line grounding fault alarm apparatus |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202903945U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103823152A (en) * | 2014-03-11 | 2014-05-28 | 国家电网公司 | Direct-current grounding detection device |
| CN105548798A (en) * | 2016-02-29 | 2016-05-04 | 珠海格力电器股份有限公司 | Grounding detection method and device for direct current bus |
| WO2018023897A1 (en) * | 2016-08-04 | 2018-02-08 | 中车戚墅堰机车有限公司 | Ground detection device for locomotive control loop, and control method thereof |
| CN114624625A (en) * | 2020-12-10 | 2022-06-14 | 国电河北龙山发电有限责任公司 | A DC grounding alarm device |
-
2012
- 2012-11-26 CN CN 201220628847 patent/CN202903945U/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103823152A (en) * | 2014-03-11 | 2014-05-28 | 国家电网公司 | Direct-current grounding detection device |
| CN105548798A (en) * | 2016-02-29 | 2016-05-04 | 珠海格力电器股份有限公司 | Grounding detection method and device for direct current bus |
| WO2018023897A1 (en) * | 2016-08-04 | 2018-02-08 | 中车戚墅堰机车有限公司 | Ground detection device for locomotive control loop, and control method thereof |
| CN114624625A (en) * | 2020-12-10 | 2022-06-14 | 国电河北龙山发电有限责任公司 | A DC grounding alarm device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202494775U (en) | Calibrator for DC system insulation device | |
| CN202903945U (en) | Direct-current system line grounding fault alarm apparatus | |
| CN203164326U (en) | Digital display type detection device of resistor strain sensor | |
| CN2549477Y (en) | DC system ground fault tester | |
| CN102706443B (en) | Transformer fault detection device based on analysis of vibration signals | |
| CN104316883A (en) | Alternating current entering alarming device of transformer substation direct current power source system | |
| CN204228942U (en) | The line fault observation circuit of current transformer | |
| CN103675606B (en) | Bridge-type DC Line Fault monitoring alarm | |
| CN201828359U (en) | On-line temperature sensor detection circuit | |
| CN203909213U (en) | Photovoltaic direct current 1000V insulation monitoring device | |
| CN202339390U (en) | Bad contact detection device for instrument test line | |
| CN201828236U (en) | Cable testing circuit | |
| CN104215913A (en) | Analogue grounding tester used for direct-current power | |
| CN106226601A (en) | A kind of detection device of weak current automatization insulation resistance | |
| CN210347761U (en) | Portable signal monitor | |
| CN203396891U (en) | Transformer wire fracture detection device | |
| CN104330762B (en) | Line fault detection circuit for current transformer | |
| CN202522654U (en) | Low-current grounding fault line selection device | |
| CN217212918U (en) | Single-loop starter insulation detection device | |
| CN216082903U (en) | True effective value alternating-current millivolt measuring voltmeter for teaching experiment | |
| CN206420541U (en) | A kind of liquid level sensor device for detecting performance | |
| CN202748125U (en) | Transformer fault detection device based on vibration signal analysis | |
| CN200941111Y (en) | Neutral point resistance information detection recorder | |
| CN203630273U (en) | Bridge-type direct-current fault monitoring alarm | |
| CN203811782U (en) | A DC power detection device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20130424 |