CN104316825B - Low-voltage customer connection box of electric energy meter auditing method and system - Google Patents
Low-voltage customer connection box of electric energy meter auditing method and system Download PDFInfo
- Publication number
- CN104316825B CN104316825B CN201410664887.4A CN201410664887A CN104316825B CN 104316825 B CN104316825 B CN 104316825B CN 201410664887 A CN201410664887 A CN 201410664887A CN 104316825 B CN104316825 B CN 104316825B
- Authority
- CN
- China
- Prior art keywords
- electric energy
- energy meter
- test signal
- signal
- low
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000012360 testing method Methods 0.000 claims abstract description 78
- 238000001514 detection method Methods 0.000 claims description 13
- 238000012550 audit Methods 0.000 claims description 12
- 230000005611 electricity Effects 0.000 claims description 9
- 238000012545 processing Methods 0.000 claims description 3
- 230000008878 coupling Effects 0.000 claims 1
- 238000010168 coupling process Methods 0.000 claims 1
- 238000005859 coupling reaction Methods 0.000 claims 1
- 238000007689 inspection Methods 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 description 8
- 238000010586 diagram Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000008447 perception Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Landscapes
- Monitoring And Testing Of Transmission In General (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
A kind of low-voltage customer connection box of electric energy meter auditing method provided by the invention, comprises the following steps：S1. test signal is loaded on the power line of user terminal；S2. test signal is detected in the leading-out terminal of electric energy meter corresponding with user terminal；S3. according to the leading-out terminal test signal in target electric energy meter, the wiring result of electric energy meter is judged；Wiring situation that can be to the electric energy meter of user terminal is accurately detected, and can accurate judgement wiring result it is whether correct, so as to eliminate user power utilization unjust phenomenon, and operated under non-power down mode, effectively avoid because have a power failure check to caused by user than just with loss, and reducing work difficulty.
Description
Technical field
The present invention relates to power domain, more particularly to a kind of low-voltage customer connection box of electric energy meter auditing method and system.
Background technology
Electric energy meter is the instrument for being recorded to the power consumption of electricity consumption user, generally for low-voltage customer,
Electric energy meter leading-out terminal connects access customer, and carries out that Every household has an ammeter, but tends to occur electric energy meter outlet and even misuse family
Situation, cause user can not be accurately corresponding with electric energy meter, in turn result in and wrong friendship occurs when expense is paid, so as to cause user
Between using unjust phenomenon (i.e. lacking more than electricity consumption pays dues, and electricity consumption is much less to pay dues), it is, therefore, desirable to provide it is a kind of for pair
The method that the wiring condition of the electric energy meter of low-voltage customer is checked, the wiring condition of the electric energy meter of low-voltage customer can be carried out
Accurate judgement, the electricity consumption eliminated between user use unjust phenomenon.
The content of the invention
In view of this, can it is an object of the invention to provide a kind of low-voltage customer connection box of electric energy meter auditing method and system
Accurate judgement is carried out to the wiring condition of the electric energy meter of low-voltage customer, the electricity consumption eliminated between user uses unjust phenomenon.
A kind of low-voltage customer connection box of electric energy meter auditing method provided by the invention, comprises the following steps：
S1. test signal is loaded on the power line of user terminal；
S2. test signal is detected in the leading-out terminal of electric energy meter corresponding with user terminal；
S3. according to the leading-out terminal test signal in target electric energy meter, the wiring result of electric energy meter is judged.
Further, in step S3, the wiring result judgement of electric energy meter is as follows：
If consistent with the test signal loaded in the test signal that leading-out terminal receives, the wiring of electric energy meter is correct；
If the test signal of test signal that leading-out terminal receives and loading it is inconsistent or in leading-out terminal without test signal,
The then wiring error of electric energy meter.
Further, in step S1, the test signal loaded on the power line of user terminal is believed for 470-480KHz radio frequency
Number.
Further, in step S1, the loading test signal produces for radio-frequency signal source, and is loaded into by termination power
On the power line of user terminal.
Further, in step S2, the test signal of target electric energy meter leading-out terminal, and decoupling circuit are detected by decoupling circuit
The test signal detected is input in processor.
Correspondingly, the invention provides a kind of low-voltage customer connection box of electric energy meter audit system, including
Signal source, for generating test signal and exporting,
Signal loading module, its input are connected with the output end of the signal source, for test signal to be loaded into use
On the power line at family end；
Signal detection module, for detecting test signal and the output of electric energy meter leading-out terminal corresponding with user；
Processor, the test signal exported for reception signal detection module, and test signal export after being handled
Shown to display；
Display, content and display for the output of reception processing device.
Further, the audit system also includes wave filter, the input of the wave filter and the output end of detection module
Connection, the output end of the wave filter are connected with the input of the processor.
Further, the wave filter is Butterworth filter.
Further, the signal loading module is termination power.
Further, the signal detection module is decoupling circuit.
Beneficial effects of the present invention：The present invention, being capable of connecing to the electric energy meter of user terminal by above-mentioned method and system
Wire condition is accurately detected, and can accurate judgement wiring result it is whether correct, so as to eliminate user power utilization unfairness
Phenomenon, and operated under non-power down mode, effectively avoid because have a power failure check to caused by user than just with loss,
And work difficulty is reduced, and can effectively avoid being verified and to circuit by way of disconnecting line in conventional method
Caused by huge injury.
Brief description of the drawings
The invention will be further described with reference to the accompanying drawings and examples：
Fig. 1 is the flow chart of auditing method of the present invention.
Fig. 2 is the theory diagram of the audit system of the present invention.
Fig. 3 is the circuit theory diagrams of the termination power of the present invention.
Fig. 4 is equivalent schematic diagram of the electric energy meter of the present invention in supply line.
Fig. 5 is the equivalent circuit diagram that radiofrequency signal is transmitted on electric energy meter and power line in the present invention.
Embodiment
Fig. 1 is the flow chart of the auditing method of the present invention, and Fig. 2 is the theory diagram of the audit system of the present invention, and Fig. 3 is this
The circuit theory diagrams of the termination power of invention, Fig. 4 are equivalent schematic diagram of the electric energy meter of the present invention in supply line, as schemed institute
Show, a kind of low-voltage customer connection box of electric energy meter auditing method provided by the invention, comprise the following steps：
Step S1. loads test signal on the power line of user terminal, wherein, test signal is that have existing radiofrequency signal
Source is produced, and identification signal can be added in test signal, such as：Identification code, the identification code are generated by coding circuit
And be sent in signal source, coding circuit can be random code or designated code when generating identification code, that is to say, that
When coding circuit generation random code is, it is necessary to which the random code is sent in processor, presented by display, inform work people
Member, then could electric energy meter leading-out terminal by the identification code that detects whether with the current caused random code of the coding circuit
It is consistent to correspond to so as to judge whether wiring is correct, and test signal is loaded into user by termination power caused by radio-frequency signal source
On the power line at end；
S2. test signal is detected in the leading-out terminal of electric energy meter corresponding with user, wherein, signal-under-test is to pass through decoupling
What circuit was detected, wherein, because present residential neighborhoods are typically provided special meter room, the ammeter of a building user
Concentrate in together, such as, number is 1-1 user, and its corresponding ammeter should also be 1-1；
S3. according to the leading-out terminal test signal in target electric energy meter, the wiring result of electric energy meter is judged.
In step S3, the wiring result judgement of electric energy meter is as follows：
If consistent with the test signal loaded in the test signal that leading-out terminal receives, the wiring of electric energy meter is correct, i.e.,
It is to say：If tested by the test signal with identification code, then the test detected by the leading-out terminal in electric energy meter
Identification code in signal should be consistent with identification code caused by coding circuit, then prove electric energy meter wiring be it is correct, when
So can not also be by identification code, for example use identification curve, then it is required that identification curve is in user terminal power line and electric energy meter
The basic trend that is showed of leading-out terminal should be consistent, but the track for being not required for its curve is completely superposed, because checking
During, power line is constantly in working condition, certain interference can be produced to signal, but the interference should be controllable
(not influenceing test result)；
If the test signal of test signal that leading-out terminal receives and loading it is inconsistent or in leading-out terminal without test signal,
The then wiring error of electric energy meter, if the test signal for test signal and the user terminal loading that electric energy meter receives in leading-out terminal goes out
It is existing inconsistent, such as identification code, in the case of wiring error, it may come in the radiofrequency signal that the leading-out terminal of electric energy meter receives
From in Radio frequency interference caused by power line transmission electric energy (although the frequency of the electric energy meter of low-voltage customer is very low, due to electric energy
The characteristics of table itself, can equally produce Radio frequency interference), disturbed in other words caused by other radio frequency sources, be likely to occur wiring error
In the case of, the leading-out terminal of electric energy meter still has radiofrequency signal, but completely can not be corresponding with the test signal of loading；When
So, when user terminal loads test signal, leading-out terminal then proves wiring error (even if power line is not in work shape without test signal
State).
In the present embodiment, in step S1, the test signal loaded on the power line of user terminal is penetrating for 470-480KHz
Frequency signal, as shown in figure 4, due to voltage transformer summation current transformer in electric energy meter be present, therefore, electric energy meter can be equivalent to
Current Mutual Inductance coil, i.e., shown in Fig. 4, L1 and L3 represent current transformer, and L2 and L4 represent voltage transformer, therefore, when penetrating
When frequency signal passes through electric energy meter, high-frequency signal deep fades will be caused, Fig. 5 flows through two electricity shown in two Fig. 4 for signal
Equivalent circuit during energy table, wherein
Wherein Z represents the characteristic impedance of transmission line；γ represents propagation coefficient, and it was found from above formula, radiofrequency signal is in low tension
Attenuation degree in the line of force is unrelated with frequency, is only influenceed by electric wire itself unit resistance, electric capacity and inductance, therefore, from Fig. 4
It can be seen that with Fig. 5：Perception is presented in transmission line, and the degree of decay is with the growth of the frequency and transmission range of transmission signal
And increase, as transmission range increases and the rise of signal frequency when power line signal transmits, the decay of channel will sharply increase,
Proved from above-mentioned principle and experiment：When signal is higher than 500KHz, radiofrequency signal flows through sharp-decay after electric energy meter, causes electricity
The leading-out terminal of energy table can not obtain test signal, even if wiring correctly can not equally obtain, so as to cause test result to be forbidden
Really, as signal frequency is less than 450KHz, then as shown in figure 4, the test signal loaded is due to flowing through its attenuation degree after table 1
Not enough, the test signal that is loaded into the power line of 1 corresponding user of table can be equally detected in the leading-out terminal of table 2, equally made
It is inaccurate into test result, therefore, use frequency to make as detection signal for the carrier signal of 470~480kHz frequency range
It is the most accurate to obtain test result, wherein, in Fig. 5, R, L, G and C are respectively the unit length of the conductor in power line and electric energy meter
Series resistance, series inductance, shunt conductance and shunt capacitance, △ x represent unit length.
In the present embodiment, in step S1, the loading test signal produces for radio-frequency signal source, and is added by termination power
It is downloaded on the power line of user terminal, passes through the effect of termination power so that realizes and isolate between signal source and power line, not to electricity
Line of force efficiency of transmission produces any influence.
In the present embodiment, in step S2, the test signal of target electric energy meter leading-out terminal is detected by decoupling circuit, and decouple
The test signal detected is input in processor by circuit, passes through the effect of decoupling circuit so that signal receiving end and electric power
Isolation is realized between line, any influence is not produced on power line transmission efficiency.
Correspondingly, present invention also offers a kind of low-voltage customer connection box of electric energy meter audit system, including：
Signal source, for generating test signal and exporting, wherein, signal source uses existing radio-frequency signal source, and instrument takes
With conveniently, cost is more cheap, certainly, coding circuit can also be set to be used to produce identification code, identification code bag in signal source
Include random code or the indication code according to caused by the instruction of staff, and by termination power by the identification code and radiofrequency signal
It is coupled on power line；
Signal loading module, its input are connected with the output end of the signal source, for test signal to be loaded into use
On the power line at family end；Wherein, signal loading module uses termination power, as shown in figure 3, termination power include electric capacity C1, every
Enter Rv2 and diode D1 and diode D2 from transformer T1, piezo-resistance, wherein, diode D1 and diode D2 are used to increase
The antisurge interference on forceful electric power road, and the voltage of power circuit is clamped down on, electric capacity C1 is isolation capacitance, is prevented on power line
Line voltage impacts to radiofrequency signal, and electric capacity C1 and isolating transformer composition high-pass filter, passes through said structure
Termination power, good protection can be formed to devices such as signal sources, extends the service life of system；
Signal detection module, for detecting test signal and the output of electric energy meter leading-out terminal corresponding with user, wherein, letter
Number detection module uses decoupling circuit, and certainly, the decoupling circuit uses existing circuit；
Processor, the test signal exported for reception signal detection module, and test signal are output to after being handled
Display is shown that the test signal that decoupling circuit exports is further processed processor, and be converted into can be by work
Make the content of personnel's reading, such as identification code, or without contents such as test signals
Display, content and display for the output of reception processing device.
In the present embodiment, the audit system also includes wave filter, the input of the wave filter and detection module it is defeated
Go out end connection, the output end of the wave filter is connected with the input of the processor, and the wave filter filters for Butterworth
Device, can strengthen the accuracy of test result, and be easy to processor to work.
Finally illustrate, the above embodiments are merely illustrative of the technical solutions of the present invention and it is unrestricted, although with reference to compared with
The present invention is described in detail good embodiment, it will be understood by those within the art that, can be to the skill of the present invention
Art scheme is modified or equivalent substitution, and without departing from the objective and scope of technical solution of the present invention, it all should cover at this
Among the right of invention.
Claims (9)
- A kind of 1. low-voltage customer connection box of electric energy meter auditing method, it is characterised in that：Comprise the following steps：S1. test signal is loaded on the power line of user terminal by termination power；S2. test signal is detected by leading-out terminal of the decoupling circuit in electric energy meter corresponding with user terminal；S3. according to the leading-out terminal test signal in target electric energy meter, the wiring result of electric energy meter is judged；Wherein, in step S1, the test signal loaded on the power line of user terminal is 470-480KHz radiofrequency signal；In step S3, the wiring result of electric energy meter is judged with the identification plots changes characterized in test signal.
- 2. low-voltage customer connection box of electric energy meter auditing method according to claim 1, it is characterised in that：In step S3, electric energy meter Wiring result judge it is as follows：If consistent with the test signal loaded in the test signal that leading-out terminal receives, the wiring of electric energy meter is correct；If the test signal of test signal that leading-out terminal receives and loading it is inconsistent or in leading-out terminal without test signal, electricity The wiring error of energy table.
- 3. low-voltage customer connection box of electric energy meter auditing method according to claim 1, it is characterised in that：It is described to add in step S1 Carry test signal to produce for radio-frequency signal source, and be loaded into by termination power on the power line of user terminal.
- 4. low-voltage customer connection box of electric energy meter auditing method according to claim 1, it is characterised in that：In step S2, pass through solution The test signal of coupling electric circuit inspection target electric energy meter leading-out terminal, and the test signal detected is input to processor by decoupling circuit In.
- A kind of 5. low-voltage customer connection box of electric energy meter audit system, it is characterised in that：IncludingSignal source, for generating test signal and exporting,Signal loading module, its input are connected with the output end of the signal source, for test signal to be loaded into user terminal Power line on；Signal detection module, for detecting test signal and the output of electric energy meter leading-out terminal corresponding with user；Processor, the test signal exported for reception signal detection module, and test signal are output to display after being handled Device shown, wherein, processor judges the wiring result of electric energy meter with the identification plots changes characterized in test signal；Display, content and display for the output of reception processing device；Wherein, signal source produces 470-480KHz radiofrequency signal As test signal and export.
- 6. low-voltage customer connection box of electric energy meter audit system according to claim 5, it is characterised in that：The audit system also wraps Wave filter is included, the input of the wave filter and the output end of detection module connect, the output end of the wave filter and the place Manage the input connection of device.
- 7. low-voltage customer connection box of electric energy meter audit system according to claim 6, it is characterised in that：The wave filter is Bart Butterworth wave filter.
- 8. low-voltage customer connection box of electric energy meter audit system according to claim 5, it is characterised in that：The signal loading module For termination power.
- 9. low-voltage customer connection box of electric energy meter audit system according to claim 5, it is characterised in that：The signal detection module For decoupling circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410664887.4A CN104316825B (en) | 2014-11-19 | 2014-11-19 | Low-voltage customer connection box of electric energy meter auditing method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410664887.4A CN104316825B (en) | 2014-11-19 | 2014-11-19 | Low-voltage customer connection box of electric energy meter auditing method and system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104316825A CN104316825A (en) | 2015-01-28 |
| CN104316825B true CN104316825B (en) | 2017-11-10 |
Family
ID=52372078
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410664887.4A Active CN104316825B (en) | 2014-11-19 | 2014-11-19 | Low-voltage customer connection box of electric energy meter auditing method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104316825B (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104714146B (en) * | 2015-03-13 | 2017-11-03 | 长沙敏特电力技术有限公司 | Ammeter is visited one house after another wiring testing device and its detection method |
| CN104914350A (en) * | 2015-07-08 | 2015-09-16 | 国家电网公司 | Detection apparatus of household-ammeter correspondence relation of residential ammeters and detection method thereof |
| CN104965147B (en) * | 2015-07-15 | 2018-07-13 | 国家电网公司 | Low-voltage customer electric energy meter is visited one house after another detecting system and detection method |
| CN105118281B (en) * | 2015-09-22 | 2018-11-13 | 杭州华春科技有限公司 | Family table relation recognition device and method |
| CN105954612A (en) * | 2016-04-29 | 2016-09-21 | 国网浙江省电力公司绍兴供电公司 | Operating equipment corresponding relation test method |
| CN105785200A (en) * | 2016-04-29 | 2016-07-20 | 国网浙江省电力公司绍兴供电公司 | Operation equipment correspondence testing device |
| CN107102289B (en) * | 2017-06-19 | 2019-10-22 | 云南电网有限责任公司曲靖供电局 | A kind of measurement loop wiring error judgment method and device |
| CN108107312B (en) * | 2017-12-04 | 2018-11-30 | 国网江苏省电力有限公司电力科学研究院 | Non- register one's residence does not power off wrong wiring of electric energy meter detection device and method |
| CN113359014A (en) * | 2021-08-11 | 2021-09-07 | 深圳英集芯科技股份有限公司 | Fool-proof method and system for chip test |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1135690A (en) * | 1994-12-31 | 1996-11-13 | 现代电子产业株式会社 | Circuit of regulating radio-requency out-put voltage level by using low-frequency signal and identifying cable-connecting path between apparatus, and method thereof |
| CN101207836A (en) * | 2006-12-18 | 2008-06-25 | 中兴通讯股份有限公司 | Method for detecting at least one cable |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB0119544D0 (en) * | 2001-08-10 | 2001-10-03 | Siemens Metering Ltd | Improvements in or relating to electricity consumption and generation meters |
| CN100501429C (en) * | 2005-12-13 | 2009-06-17 | 北京潞电电气设备厂 | Wiring identifying device and method |
| CN102162842B (en) * | 2011-05-25 | 2013-04-10 | 重庆市电力公司电力科学研究院 | Online check meter of high-voltage electric energy metering device |
| CN102981100A (en) * | 2012-12-12 | 2013-03-20 | 上海市电力公司 | Judgment method for misconnection of three-phase three-wire electric energy meter |
| CN203572912U (en) * | 2013-12-09 | 2014-04-30 | 马良 | Wiring testing device for massive quantity power supply electric energy measurement |
| CN203773002U (en) * | 2014-03-21 | 2014-08-13 | 国家电网公司 | Wire connection correctness detector for electric energy metering device |
| CN103869210B (en) * | 2014-03-21 | 2017-05-10 | 国家电网公司 | Wiring right and wrong detector for electric energy metering device in power-off state |
-
2014
- 2014-11-19 CN CN201410664887.4A patent/CN104316825B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1135690A (en) * | 1994-12-31 | 1996-11-13 | 现代电子产业株式会社 | Circuit of regulating radio-requency out-put voltage level by using low-frequency signal and identifying cable-connecting path between apparatus, and method thereof |
| CN101207836A (en) * | 2006-12-18 | 2008-06-25 | 中兴通讯股份有限公司 | Method for detecting at least one cable |
Non-Patent Citations (2)
| Title |
|---|
| 射频场感应的传导骚扰扰度试验辐射场研究;郑荐中 等;《科技资讯》;20091231(第24期);2-4 * |
| 电能表检定装置抗电磁干扰试验方法研究;韩志强 等;《电气应用》;20140930(第17期);42-45 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104316825A (en) | 2015-01-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104316825B (en) | Low-voltage customer connection box of electric energy meter auditing method and system | |
| CN100575980C (en) | Switch power source EMI noise origin internal impedance test system and assay method | |
| CN1078711C (en) | Device for sensing of electric discharges in a test object | |
| CN203554436U (en) | Conducted interference isolation circuit for low-voltage circuit line carrier communication | |
| CN108267647B (en) | Detection method and device for power conduction electromagnetic leakage protection | |
| CN1971292A (en) | Device and method for measuring internal impedance of noise source of switch power supply EMI | |
| CN207124491U (en) | Voltage detecting circuit, power transmission device and electrical power transmission system | |
| CN103163393A (en) | Electro-magnetic interference detecting system for power line conduction | |
| CN106463944A (en) | Method for detecting an open-phase condition of a transformer | |
| CN103852697B (en) | Cable partial discharge detection device | |
| CN108701983A (en) | A kind of arc fault current detector | |
| CN103513158B (en) | Damped oscillatory wave lower cable local discharge detection device and method | |
| CN205248099U (en) | After -current transformer | |
| CN107907831A (en) | Winding temperature detection circuit, temperature measurement control system and temperature monitor | |
| CN205092562U (en) | Residual current protection device | |
| CN106485899A (en) | Family table wiring test device and its method of testing based on the power frequency distortion communication technology | |
| CN104807537B (en) | Noise transducer | |
| CN203551651U (en) | A DC power system bus voltage AC component detecting circuit | |
| BR102012030126B1 (en) | method of detecting a bypass between the inputs and outputs of electricity, method of locating fraud, device for detecting a bypass between the inputs and outputs of electricity and electricity consumption meter | |
| CN207689643U (en) | Winding temperature detection circuit, temperature measurement control system and temperature monitor | |
| CN202522634U (en) | Device for detecting capacity for withstanding direct-current magnetic biasing of transformer | |
| CN104851342B (en) | A kind of anti-electricity-theft device for contact stealing and contactless stealing | |
| CN201868855U (en) | Rotor ground protection device | |
| CN104237835A (en) | Wiring detection device for straight-through current transformer | |
| CN107064722A (en) | Low-voltage customer is visited one house after another and zero detection means totally |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |