CN204215013U - Contact of electrical switch health status on-line monitoring and early warning system - Google Patents
Contact of electrical switch health status on-line monitoring and early warning system Download PDFInfo
- Publication number
- CN204215013U CN204215013U CN201420706015.5U CN201420706015U CN204215013U CN 204215013 U CN204215013 U CN 204215013U CN 201420706015 U CN201420706015 U CN 201420706015U CN 204215013 U CN204215013 U CN 204215013U
- Authority
- CN
- China
- Prior art keywords
- contact
- electrical switch
- unit
- measurement
- contact resistance
- 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 - Fee Related
Links
Abstract
The utility model proposes a kind of contact of electrical switch health status on-line monitoring and early warning system, belong to electric switch technical field.System comprises contact of electrical switch, current measuring unit, front voltage measuring unit, rear end voltage measurement unit, Measurement and analysis unit, display alarm unit and communication unit.Measurement and analysis unit utilizes the temperature, electric current and the voltage that measure, calculate temperature and variation tendency, contact resistance resistance and the variation tendency thereof of contact of electrical switch, in conjunction with multiple criterion method, the running status of real time on-line monitoring contact of electrical switch is also analyzed and is judged its health status, give display alarm unit display, through communication unit external device or control center's server transmission, timely early warning during unusual circumstance.Effectively can stop the potential safety hazard that contact exists, prior notice operations staff keep in repair, and improves the life-span of electric switch equipment and the reliability of line powering, can be applied to any occasion used with contact of electrical switch.
Description
Technical field
The utility model relates to a kind of contact of electrical switch health status on-line monitoring and early warning system, particularly a kind of according to contact resistance variation Real-Time Monitoring contact of electrical switch health status, and carries out the system of warning and early warning, belongs to electric switch technical field.
Background technology
Electric switch mainly comprises isolating switch, disconnector etc., generally all has contact.The contact resistance of contact of electrical switch is one of key factor affecting electric switch reliability.Electric switch, when normally working, requires that contact has little and stable contact resistance.Because electric switch long-time running causes the factors such as surface oxidation, the contact resistance of its contact can increase, so in application scenario that is high-power, big current, contact component can produce a large amount of Joule heats, increase loss, when these heats can not distribute in time, the local temperature of contact component is likely caused to raise rapidly, very possible like this cause contact component be out of shape, adhesion, even burn, burst, thus shorten the serviceable life of electric switch, serious causes fire or major accident etc.Because modern power systems becomes increasingly complex, a complication system may comprise thousands of electric switches, if certain electric switch wherein breaks down, fatal harm can be caused to whole electric system, therefore the performance of electric switch and the reliability and stability of quality to whole electric system play vital effect.
Having the thermel protection device of contact of electrical switch at present, is monitor for contact is overheated, adopts the mode that temperature limit judges, and when finding contact of electrical switch temperature alarm or protection act, is all generally overheated relatively more serious, even causes device damage.Not yet there is the health status of on-line monitoring contact of electrical switch, and occur that the initial stage of deterioration just can carry out the technology of diagnosis and early warning at contact of electrical switch.
Part instrument can carry out online or off-line monitoring for fever phenomenon, but for electric switch equipment, the overheated just presentation of contact, cannot find potential safety hazard.When contact has occurred that oxidation causes loose contact, if but the running current that this electric switch equipment passes through is always very little, contact part heating is also not serious, healthy hidden danger cannot be found, only after running current increases, this potential safety hazard just shows by contact is overheated, and often at this moment pinpoints the problems, overheated further deterioration or the damage that result in contact state, therefore the change of contact resistance is only the most fundamental basis judging contact of electrical switch health status.
In recent years, the intelligent instrument development of domestic detection contact resistance is very fast, many companies have been had to develop advanced instrument equipment miscellaneous, but detect the intelligent instrument of contact resistance and there are some defects, as contact resistance tester cannot real time on-line monitoring, must have a power failure measurement, and detection time is long, greatly reduce the reliability of line powering like this, testing result also relies on operations staff by virtue of experience to judge, efficiency is low.
In a word, can the heating rule of real time on-line monitoring contact of electrical switch, the degradation trend of contact resistance, analyze and judge its health status, and there is not been reported can to carry out the intelligent system of healthy early warning.
Summary of the invention
In order to overcome the deficiencies in the prior art, the utility model provides a kind of contact of electrical switch health status on-line monitoring and early warning system, this system is according to the on-line measurement analysis to contact resistance and temperature, in conjunction with the multiple criterion of design, can the health status of real time on-line monitoring contact of electrical switch, can early warning in time during unusual circumstance, effectively stop the potential safety hazard that contact exists, before breaking down, notify that operations staff keeps in repair, improve the life-span of electric switch equipment and the reliability of line powering, meet the requirement of following intelligent grid.
The utility model solves the technical scheme that its technical matters adopts:
Contact of electrical switch health status on-line monitoring and early warning system comprise contact of electrical switch (1), current measuring unit (2), front voltage measuring unit (3), rear end voltage measurement unit (4), Measurement and analysis unit (5), display alarm unit (6) and communication unit (7).
Current measuring unit (2) measures the real-time current by contact of electrical switch (1), and data is sent to Measurement and analysis unit (5), realizes the real-time current data acquisition flowing through contact of electrical switch.
Front voltage measuring unit (3) is arranged on the front end of contact of electrical switch (1), rear end voltage measurement unit (4) is arranged on the rear end of contact of electrical switch (1), measure the real-time voltage at contact of electrical switch (1) two ends respectively, and data are directly sent to Measurement and analysis unit (5).Because front voltage measuring unit (3) and rear end voltage measurement unit (4) are distributed in contact of electrical switch (1) two ends, distance is very near, centre only has contact resistance load, be purely resistive load, the voltage recorded does not have phase angle difference, and numerical value is very close, for improving measuring accuracy and anti-interference, also first can send potential difference meter (9) to, obtain voltage differential signal, then send Measurement and analysis unit (5) to.
Measurement and analysis unit (5) sends with the service data calculated the real-time running data recorded to display alarm unit (6) and shows in real time, transmits through communication unit (7) external device (8) simultaneously.
Contact of electrical switch (1) is installed temperature measurement unit (10), measure the real time temperature of contact of electrical switch (1), data are sent to Measurement and analysis unit (5), the auxiliary alarm threshold value revising contact resistance, and temperature service data, the temperature changing trend that obtained by Measurement and analysis unit (5) analytical calculation are analyzed data and temperature over-range alert data and send display alarm unit (6) to and show in real time, transmit through communication unit (7) external device (8) simultaneously.It is on the temperature service data basis measured in real time that described temperature changing trend analyzes data, calculates load change in conjunction with voltage, electric current, under elimination fluctuation of load impact, judges whether temperature occurs continuing variation tendencies such as rising, the short time rises fast.This trend is likely the reflection that deterioration appears in contact of electrical switch (1).
Measurement and analysis unit (5) utilizes the temperature measured, electric current and front, rear end voltage difference, temperature and the variation tendency thereof of contact of electrical switch (1) can be calculated, and contact resistance resistance and variation tendency thereof, analyze the health status judging contact of electrical switch (1), send display alarm unit (6) to show in real time, or transmit through communication unit (7) external device (8), upload to dispatching center's server etc., analyze, report to the police, and the healthy early warning of contact of electrical switch (1), operations staff is reminded to take maintenance measures in advance as early as possible, prevent the further deterioration of contact of electrical switch (1), stop the generation of superheating phenomenon.
When Measurement and analysis unit (5) utilizes contact resistance to carry out the health status monitoring diagnosis of contact of electrical switch (1), adopt following criterion: criterion one judges whether contact resistance exceedes the threshold value of setting, if contact resistance directly transfinites, report to the police immediately, now illustrate that contact of electrical switch (1) has gone wrong; Criterion two is that the history data of record in same Measurement and analysis unit (5) is compared, judge whether contact resistance increases gradually, if within the time period of setting, contact resistance variation general trend increases, report to the police immediately, this illustrates that contact of electrical switch (1) is continuing in deterioration; Criterion three judges whether contact resistance variation slope exceedes the threshold value of setting, if contact resistance variation slope directly transfinites, reports to the police immediately, and this illustrates that the speed of contact of electrical switch (1) deterioration is very fast.Three criterions can absolutely prove that contact of electrical switch (1) is in unsound running status, need to carry out inspection and maintenance at once.
The alarm threshold value of contact resistance generally takes empirical value, in order to more tally with the actual situation, temperature is adopted to assist the method for the alarm threshold value revising contact resistance: when contact of electrical switch (1) works in rated condition, after the contact of electrical switch recorded (1) temperature stabilization, if temperature does not exceed the alarm threshold value of setting, and contact resistance has exceeded the alarm threshold value of setting, then remind operations staff contact resistance alarm threshold value can be raised; If temperature exceedes the alarm threshold value of setting, and contact resistance does not exceed the alarm threshold value of setting, then remind operations staff contact resistance alarm threshold value can be lowered.As far as possible the method for above-mentioned correction makes contact of electrical switch (1) when rated operation, temperature monitoring and insulation resistance monitoring can be agreed, the accuracy of reporting to the police can be ensured, and in a rated operation, electrical equipment often has higher performance and efficiency, the capacity of contact of electrical switch (1) can be made full use of, avoid the impact of being reported to the police.
Compared with prior art, the utility model tool has the following advantages:
This system carries out real time on-line monitoring to contact resistance and temperature, whether exceed the threshold value of setting in conjunction with contact resistance, whether contact resistance increases gradually, whether contact resistance variation slope exceedes three criterions such as the threshold value of setting analyzes, fully can reflect the health status of contact of electrical switch, can early warning in time during unusual circumstance, effectively stop the potential safety hazard that contact exists, before breaking down, notify that operations staff keeps in repair, improve the life-span of electric switch equipment and the reliability of line powering.Adopt temperature to assist the alarm threshold value method revising contact resistance simultaneously, make contact of electrical switch when rated operation, temperature monitoring and insulation resistance monitoring can be agreed, the accuracy of reporting to the police can be ensured, and the capacity of contact of electrical switch in a rated operation, can be made full use of.In addition, the Real-Time Monitoring of service data, show or upload, also contributing to the ruuning situation that operations staff grasps circuit or system, enhance productivity and intelligence degree.
Accompanying drawing explanation
Fig. 1 is system construction drawing.
Fig. 2 is the system construction drawing adopting potential difference meter mode.
Fig. 3 is the process flow diagram utilizing contact resistance to carry out health status early warning.
In figure: 1-contact of electrical switch, 2-current measuring unit, 3-front voltage measuring unit, 4-rear end voltage measurement unit, 5-Measurement and analysis unit, 6-display alarm unit, 7-communication unit, 8-external unit, 9-potential difference meter, 10-temperature measurement unit.
Embodiment
Below in conjunction with accompanying drawing, the utility model is described in further detail:
As shown in Figure 1, contact of electrical switch health status on-line monitoring early warning system comprises contact of electrical switch (1), current measuring unit (2), front voltage measuring unit (3), rear end voltage measurement unit (4), Measurement and analysis unit (5), display alarm unit (6) and communication unit (7).Display alarm unit (6) can adopt the liquid crystal display, the LED charactron that are arranged on cabinet external body, and traditional sound, light warning device etc.; Communication unit (7) can adopt RS232 serial ports, USB interface, bluetooth etc., also can be cable network or radio network interface; Accordingly, external unit (8) can be USB flash disk, hand-held set, notebook computer etc., also can be the webserver of control center.
Current measuring unit (2) measures the real-time current by contact of electrical switch (1), and data is sent to Measurement and analysis unit (5); Front voltage measuring unit (3) is arranged on the front end of contact of electrical switch (1), rear end voltage measurement unit (4) is arranged on the rear end of contact of electrical switch (1), measure the real-time voltage at contact of electrical switch (1) two ends respectively, and data are sent to Measurement and analysis unit (5); Measurement and analysis unit (5) utilizes the front and back ends voltage and current measured, and calculates the contact resistance of contact of electrical switch (1).
Temperature measurement unit (10) is arranged on contact of electrical switch (1), measure the real time temperature of contact of electrical switch (1), and data are sent to Measurement and analysis unit (5), realize the temperature signal Real-time Collection of contact of electrical switch, report to the police, according to temperature changing trend early warning etc. for temperature over-range.
Measurement and analysis unit (5) utilizes the temperature measured, electric current and front, rear end voltage difference, temperature and the variation tendency thereof of contact of electrical switch (1) can be calculated, and contact resistance resistance and variation tendency thereof, analyze the health status judging contact of electrical switch (1), send display alarm unit (6) to show in real time, or transmit through communication unit (7) external device (8), upload to dispatching center's server etc., analyze, report to the police, and the healthy early warning of contact of electrical switch (1), operations staff is reminded to take maintenance measures in advance as early as possible, prevent the further deterioration of contact of electrical switch (1), stop the generation of superheating phenomenon.The health status of real time on-line monitoring contact of electrical switch, timely early warning during unusual circumstance, effectively can stop the potential safety hazard that contact exists, improve the life-span of electric switch equipment and the reliability of line powering.
Measurement and analysis unit (5) is according to real-time running datas such as the voltage, electric current and the temperature that record, also can calculate as service datas such as active power, reactive power, power factor, electricity, jointly send display alarm unit (6) to show in real time, analyze or reference for operations staff, also can transmit through communication unit (7) external device (8) simultaneously.
The key measuring contact of electrical switch (1) contact resistance is that contact both end voltage is poor, as shown in Figure 2, the two ends real-time voltage signal that front voltage measuring unit (3) and rear end voltage measurement unit (4) obtain, first can send potential difference meter (9) to, obtain voltage differential signal, then send Measurement and analysis unit (5) to.Because front voltage measuring unit (3) and rear end voltage measurement unit (4) are distributed in contact of electrical switch (1) two ends, distance is very near, centre only has contact resistance load, be purely resistive load, therefore the voltage recorded does not have phase angle difference, numerical value is very close, can consider to adopt potential difference meter (9), if the metering system without potential difference meter (9) shown in employing Fig. 1, system architecture is simpler, but to front voltage measuring unit (3), the measuring accuracy of rear end voltage measurement unit (4), anti-interference is had higher requirement, and adopt the system architecture of potential difference meter (9) slightly complicated, but measuring accuracy is higher, anti-interference is stronger.
As Fig. 1, shown in Fig. 2, contact of electrical switch (1) is installed temperature measurement unit (10), measure the real time temperature of contact of electrical switch (1), and data are sent to Measurement and analysis unit (5), can according to the temperature variation of contact of electrical switch (1), the auxiliary alarm threshold value revising contact resistance, make monitoring function more perfect, and by temperature service data, the temperature changing trend analysis data obtained by Measurement and analysis unit (5) analytical calculation and temperature over-range alert data send display alarm unit (6) to and show in real time, transmit through communication unit (7) external device (8) simultaneously.Can the temperature of real time on-line monitoring contact of electrical switch and variation tendency thereof, can early warning in time during unusual circumstance, effectively can stop the potential safety hazard that contact exists, before breaking down, notify that operations staff keeps in repair, improve the life-span of electric switch equipment and the reliability of line powering.
As shown in Figure 3, when Measurement and analysis unit (5) utilizes contact resistance to carry out the health status monitoring diagnosis of contact of electrical switch (1), adopt following criterion: criterion one judges whether contact resistance exceedes the threshold value of setting, if contact resistance directly transfinites, once running current reaches rated current, probably will there is superheating phenomenon, therefore transfinite, report to the police, according to field operation experiences, the contact resistance of contact of breaker generally can not higher than 50 micro-ohms; Criterion two is that the history data of record in same Measurement and analysis unit (5) is compared, judge whether contact resistance increases gradually, if within the time period of setting, contact resistance variation general trend increases, represent contact of electrical switch (1) health be in continuous worsening in, should overhaul, avoid worsening further and reporting to the police; Criterion three is the situations occurring that contact resistance rises sharply, and the threshold value whether exceeding setting with contact resistance variation slope judges, owing to being subject to the impact of certain factor, may causing contact of electrical switch (1) that the damage of burst occurs, should report to the police immediately.Three criterions can absolutely prove that contact of electrical switch (1) is in unsound running status, need to carry out inspection and maintenance.
Generally, the object that contact of electrical switch (1) temperature exceedes a certain limit value and reports to the police prevents contact of electrical switch (1) overheated, and overheated root to be contact resistance excessive.But the factor such as operating condition, running environment exists directly impact to the temperature of contact of electrical switch (1), such as, when contact resistance is identical, time time electric current is little, low, the electric current of temperature is large, temperature is high; Time function of environment heat emission is good, when temperature low, weak heat-dissipating, temperature is high etc., therefore, adopt the method utilizing temperature to assist the alarm threshold value revising contact resistance, as shown in Figure 3, when contact of electrical switch (1) works in rated condition, after the contact of electrical switch recorded (1) temperature stabilization, if temperature does not exceed the alarm threshold value of setting, and contact resistance has exceeded the alarm threshold value of setting, then remind operations staff contact resistance alarm threshold value can be raised; If temperature exceedes the alarm threshold value of setting, and contact resistance does not exceed the alarm threshold value of setting, then remind operations staff contact resistance alarm threshold value can be lowered.As far as possible the method for above-mentioned correction makes contact of electrical switch (1) when rated operation, temperature monitoring and insulation resistance monitoring can be agreed, the accuracy of reporting to the police can be ensured, and in a rated operation, electrical equipment often has higher performance and efficiency, can make full use of the capacity of contact of electrical switch (1).
The foregoing is only better embodiment of the present utility model; not in order to limit the utility model; all within spirit of the present utility model and principle, any amendment done, equivalent replacement, improvement etc., all should be included within protection domain of the present utility model.
Claims (5)
1. contact of electrical switch health status on-line monitoring and early warning system, it is characterized in that: system comprises contact of electrical switch (1), current measuring unit (2), front voltage measuring unit (3), rear end voltage measurement unit (4), Measurement and analysis unit (5), display alarm unit (6) and communication unit (7), current measuring unit (2) measures the real-time current by contact of electrical switch (1), and data are sent to Measurement and analysis unit (5), front voltage measuring unit (3) is arranged on the front end of contact of electrical switch (1), rear end voltage measurement unit (4) is arranged on the rear end of contact of electrical switch (1), measure the real-time voltage at contact of electrical switch (1) two ends respectively, and data are sent to Measurement and analysis unit (5),
Measurement and analysis unit (5) utilizes the front and back ends voltage and current measured, calculate the contact resistance of contact of electrical switch (1), Measurement and analysis unit (5) judges the health status of contact of electrical switch (1) according to the variation tendency of contact resistance and size real-time analysis, and reports to the police through display alarm unit (6) and communication unit (7) and notify operations staff;
Measurement and analysis unit (5) sends with the service data calculated the real-time running data recorded to display alarm unit (6) and shows in real time, transmits through communication unit (7) external device (8) simultaneously.
2. contact of electrical switch health status on-line monitoring according to claim 1 and early warning system, it is characterized in that: the two ends real-time voltage signal that front voltage measuring unit (3) and rear end voltage measurement unit (4) obtain, first can send potential difference meter (9) to, obtain voltage differential signal, then send Measurement and analysis unit (5) to.
3. contact of electrical switch health status on-line monitoring early warning system according to claim 1, it is characterized in that: contact of electrical switch (1) is installed temperature measurement unit (10), measure the real time temperature of contact of electrical switch (1), data are sent to Measurement and analysis unit (5), the auxiliary alarm threshold value revising contact resistance, and by temperature service data, the temperature changing trend analysis data obtained by Measurement and analysis unit (5) analytical calculation and temperature over-range alert data send display alarm unit (6) to and show in real time, transmit through communication unit (7) external device (8) simultaneously.
4. contact of electrical switch health status on-line monitoring according to claim 1 and early warning system, it is characterized in that: when Measurement and analysis unit (5) carries out the health status monitoring diagnosis of contact of electrical switch (1), criterion one judges whether contact resistance exceedes the threshold value of setting, exceeded and then reported to the police; Criterion two is that the history data of record in same Measurement and analysis unit (5) is compared, and judges whether contact resistance increases gradually, if within the time period of setting, contact resistance variation general trend increases then warning; Criterion three is the situations occurring that contact resistance rises sharply, and the threshold value whether exceeding setting with contact resistance variation slope judges, has exceeded and has then reported to the police.
5. contact of electrical switch health status on-line monitoring according to claim 3 and early warning system, it is characterized in that: utilize temperature to assist the method for alarm threshold value revising contact resistance to be, when contact of electrical switch (1) works in rated condition, after the contact of electrical switch recorded (1) temperature stabilization, if temperature does not exceed the alarm threshold value of setting, and contact resistance has exceeded the alarm threshold value of setting, then remind operations staff contact resistance alarm threshold value can be raised; If temperature exceedes the alarm threshold value of setting, and contact resistance does not exceed the alarm threshold value of setting, then remind operations staff contact resistance alarm threshold value can be lowered.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420706015.5U CN204215013U (en) | 2014-11-23 | 2014-11-23 | Contact of electrical switch health status on-line monitoring and early warning system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420706015.5U CN204215013U (en) | 2014-11-23 | 2014-11-23 | Contact of electrical switch health status on-line monitoring and early warning system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204215013U true CN204215013U (en) | 2015-03-18 |
Family
ID=52983674
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420706015.5U Expired - Fee Related CN204215013U (en) | 2014-11-23 | 2014-11-23 | Contact of electrical switch health status on-line monitoring and early warning system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204215013U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104345270A (en) * | 2014-11-23 | 2015-02-11 | 哈尔滨理工大学 | On-line electric switch contact health state monitoring and early warning system |
| CN110809720A (en) * | 2017-10-12 | 2020-02-18 | 株式会社Lg化学 | System and method for diagnosing contactor life by using contactor coil current |
| CN115980450A (en) * | 2023-02-22 | 2023-04-18 | 上海威固信息技术股份有限公司 | Micro-fluidic chip contact resistance detection design method and system |
-
2014
- 2014-11-23 CN CN201420706015.5U patent/CN204215013U/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104345270A (en) * | 2014-11-23 | 2015-02-11 | 哈尔滨理工大学 | On-line electric switch contact health state monitoring and early warning system |
| CN110809720A (en) * | 2017-10-12 | 2020-02-18 | 株式会社Lg化学 | System and method for diagnosing contactor life by using contactor coil current |
| US11287476B2 (en) | 2017-10-12 | 2022-03-29 | Lg Energy Solution, Ltd. | System and method for diagnosing contactor lifetime by using contactor coil current |
| CN110809720B (en) * | 2017-10-12 | 2022-07-08 | 株式会社Lg新能源 | System and method for diagnosing contactor life by using contactor coil current |
| CN115980450A (en) * | 2023-02-22 | 2023-04-18 | 上海威固信息技术股份有限公司 | Micro-fluidic chip contact resistance detection design method and system |
| CN115980450B (en) * | 2023-02-22 | 2024-03-12 | 上海威固信息技术股份有限公司 | Micro-fluidic chip contact resistance detection design method and system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104345270A (en) | On-line electric switch contact health state monitoring and early warning system | |
| CN107367673B (en) | A kind of arrester valve piece resistance operating status diagnostic method | |
| CN204215013U (en) | Contact of electrical switch health status on-line monitoring and early warning system | |
| CN101539612A (en) | System for on-line monitoring of running quality of battery | |
| CN104571058A (en) | Remote online intelligent monitoring system for storage batteries | |
| CN104483633B (en) | Lead-acid accumulator monitoring system | |
| CN105371967A (en) | Power cable joint temperature measuring device | |
| CN104959722B (en) | A kind of resistance soldering turret with failure detector | |
| CN204515489U (en) | Accumulator remote online intelligent monitor system | |
| CN103018603A (en) | Diagnostic method of abnormal operating state of switch cabinet | |
| CN105467309A (en) | State evaluation method and maintenance strategy for contact of high-voltage circuit breaker | |
| CN105548867A (en) | Diagnostic system and diagnostic method of contact state of high-voltage circuit breaker | |
| CN106443362A (en) | Power distribution network fault detection system | |
| WO2023221595A1 (en) | System for failure diagnosis of insulation detection function of electric vehicle, method, and device | |
| CN201522959U (en) | Intelligent high pressure vacuum circuit breaker | |
| CN203100908U (en) | An over-temperature alarm indicator of a connecting fitting | |
| CN103616586A (en) | Low-voltage insulation and temperature detection device | |
| CN213544779U (en) | Battery monitoring system for track maintenance equipment | |
| CN101943727B (en) | Online detection device of surge protector | |
| CN204241111U (en) | A kind of switch cubicle accident intelligent early-warning device | |
| CN204913047U (en) | Soldering turret detection device | |
| CN205160210U (en) | Novel join in marriage and become intelligent monitor terminal | |
| CN106383298A (en) | Power distribution network fault detection method | |
| CN103592507A (en) | Voltage loop alarm for metering devices of transformer station | |
| CN208369206U (en) | A kind of arc light protective device with TEV detection |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150318 Termination date: 20171123 |