CN107525995B - Line calibration auxiliary equipment - Google Patents
Line calibration auxiliary equipment Download PDFInfo
- Publication number
- CN107525995B CN107525995B CN201710711731.0A CN201710711731A CN107525995B CN 107525995 B CN107525995 B CN 107525995B CN 201710711731 A CN201710711731 A CN 201710711731A CN 107525995 B CN107525995 B CN 107525995B
- Authority
- CN
- China
- Prior art keywords
- switch
- input
- cable
- control unit
- unit
- 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
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
Abstract
The invention belongs to the technical field of cable checking equipment, and particularly relates to auxiliary line checking equipment. The invention discloses a cable calibration auxiliary device, aiming at solving the problems of equipment damage and potential safety hazard caused by the fact that the cable to be tested cannot be judged in advance and the cable calibration operation is directly carried out when the cable is calibrated by adopting a conventional method. The auxiliary equipment comprises an input unit, a control unit, an execution unit and a power supply unit; firstly, the voltage between the cable to be tested and the grounding grid is input into the control unit through the input unit, and then the control unit compares and analyzes the input voltage and controls the execution unit to act according to a comparison result. The cable checking auxiliary equipment provided by the invention is used for carrying out auxiliary cable checking operation on the cable, so that the safety of the cable checking process can be improved, and the safety protection on the equipment and operators is increased.
Description
Technical Field
The invention belongs to the technical field of cable checking equipment, and particularly relates to auxiliary line checking equipment.
Background
In the construction process of the electric instrument, the construction quantity of the cable wires is large, and each cable wire which is finished by end connection construction needs to be subjected to wire correction one by one, so that correct connection of lines is guaranteed.
Referring to fig. 1, the conventional method for calibrating the cable conductor at present is as follows: firstly, one end of a cable core wire to be tested is reliably connected with the grounding grid by a connecting wire. And then, adjusting the multimeter to a resistance ohmic gear, reliably connecting one meter pen of the multimeter with the grounding grid, and reliably connecting the other meter pen of the multimeter with the other end of the cable core wire to be tested. And then, testing the cable core wire to be tested by using a universal meter.
However, when the cable conductor is subjected to the cable calibration operation by the above conventional method, it is not ensured whether the cable core to be tested is in a charged state. If the core wire of the cable to be tested is in a charged state, a single-phase grounding is formed when the cable to be tested is connected with the grounding grid through a universal meter or a connecting wire. Thus, not only can the multimeter be damaged, but also sparks or grounding arcs can be generated at the contact position of the cable to be tested and the grounding grid, and safety accidents such as electric shock, burning or electric fire of personnel can be caused. In addition, if the cable to be tested is a cable in normal live operation, the live operation equipment can be stopped, and the normal operation of the equipment is affected.
Disclosure of Invention
The invention provides a cable calibration auxiliary device, aiming at solving the problems that when a conventional method is adopted to perform cable calibration operation on a cable, the damage and potential safety hazard to equipment are caused because the cable to be tested cannot be judged in advance and the cable calibration operation is directly performed. The auxiliary equipment comprises an input unit, a control unit, an execution unit and a power supply unit; wherein the content of the first and second substances,
the input unit comprises an input interface and an output interface; the input interface is divided into two ends, one end of the input interface is connected with one port of the cable core wire to be tested, and the other end of the input interface is connected with the grounding grid; the output interface is connected with the control unit;
the control unit comprises an input module, an output module and a power module, and is provided with a preset voltage value; the input module is connected with an output interface of the input unit, the output module is connected with the execution unit, and the power supply module is connected with the power supply unit;
the execution unit comprises a working loop and an alarm loop; when the voltage value between the two ends of the input interface is lower than a preset voltage value, the control unit controls the working circuit to form a closed loop so that a cable core wire to be tested is connected with a grounding network; when the voltage value between the two ends of the input interface is higher than a preset voltage value, the control unit controls the alarm circuit to form a closed loop circuit to give an alarm prompt;
the power supply unit comprises a power supply and a first switch and is used for supplying power to the control unit and the execution unit.
Preferably, a bridge rectifier block is arranged in the input unit; the input end of the bridge rectifier block is connected with the input interface, and the output end of the bridge rectifier block is connected with the output interface.
Preferably, the working circuit comprises a second switch, a third switch, a time relay, an intermediate relay, and a power supply and a first switch in the power supply unit; the on-off of the second switch is controlled by an output module in the control unit, a coil of the time relay is connected with a contact in parallel and is positioned at the downstream position of the third switch, a coil of the intermediate relay is connected with the contact of the time relay in series, and the contact of the intermediate relay is positioned between two ends of the input interface in the input unit and is connected with the bridge rectifier block in parallel.
Further preferably, the operation circuit further includes a first buzzer connected in parallel to a coil of the intermediate relay.
Preferably, the alarm circuit sequentially comprises a fourth switch, a second buzzer, a power supply and a first switch in the power supply unit; the on-off of the fourth switch is controlled by an output module in the control unit.
Preferably, the device also comprises an external meter pen, wherein the external meter pen comprises an insulated pen container and a conductive pointer; the pen container is of a hollow structure, and the pointer is positioned inside the pen container; one end of the pointer extends out of the pen container and is in contact with a cable core wire to be tested, and the other end of the pointer is connected with one end of the input interface in the input unit.
Further preferably, the second switch is located inside the barrel, and the pointer can move axially relative to the barrel; when the pointer carries out axial recovery action relative to the pen container, the second switch is touched and switched to a closed state when being in an open state.
Preferably, a return spring is arranged between the pointer and the second switch and used for pushing the pointer to axially extend out along the pen container.
Preferably, the pen container is of a split structure in threaded connection.
Preferably, the control unit is an overvoltage protection relay.
When the auxiliary cable calibration device is adopted to perform auxiliary cable calibration operation on the cable core, the auxiliary cable calibration device has the following beneficial effects:
1. in the line calibration auxiliary equipment, firstly, the bridge rectifier block is arranged in the input unit, the voltage between the cable core wire to be tested and the grounding grid is input into the control unit, then the control unit compares and judges the input voltage, and then the execution unit is controlled to act according to the judgment result, for example, the cable core wire to be tested and the grounding grid are directly communicated or alarm prompt is carried out. Therefore, before the cable core wire to be tested is subjected to cable calibration, whether the cable core wire is electrified or not can be judged firstly, and then follow-up operation is directly performed according to the judgment result, so that the danger existing when the cable core wire is directly subjected to cable calibration operation for the electrified cable can be avoided, the safety protection of equipment and operators is increased, and the safety of the cable calibration operation process is improved.
2. In the working circuit of the invention, two progressive circuit loops are formed in the working circuit by arranging a second switch and a time relay which are connected with the control unit. The method comprises the steps of firstly, controlling the connection of a second switch through a control unit to form a first circuit loop, enabling a time relay to enter a time delay stage, reserving time for voltage value comparison for the control unit, and then judging whether the second switch is finally connected or disconnected according to an analysis result of the control unit, namely, whether the second circuit loop is formed or not, so that the connection or disconnection between a cable to be tested and a grounding grid is finally controlled. Therefore, the accuracy of the whole control process is improved and the safety of line calibration operation is improved through the two progressive circuit loops.
3. In the invention, the external meter pen is arranged, and the third switch is arranged in the external meter pen, so that only when the meter pen is in stable contact with the cable core wire to be tested, the working loop forms a closed loop to work when the third switch is in a closed state. Therefore, the accidental closing of the working loop is avoided, the controllability and the safety of the operation process are improved, an operator is connected with the port of the cable core wire to be tested through the handheld external meter pen, and the convenience and the operation efficiency of operation are greatly improved.
Drawings
FIG. 1 is a schematic connection diagram of a cable to be tested during cable calibration by a conventional method;
FIG. 2 is a schematic block diagram of the line calibration auxiliary apparatus of the present invention;
FIG. 3 is an electrical schematic of the line calibration aid of the present invention;
FIG. 4 is a schematic structural diagram of an external stylus of the present invention;
FIG. 5 is a schematic diagram of a first connection of a cable to be tested during auxiliary cable calibration by using the auxiliary cable calibration device of the present invention;
fig. 6 is a schematic diagram of a second connection when the auxiliary line calibration device of the present invention is used to perform auxiliary line calibration with a cable to be tested.
Detailed Description
The technical scheme of the invention is further described below by combining the attached drawings.
Referring to fig. 2 and 3, the line calibration auxiliary device of the present invention includes an input unit 1, a control unit 2, an execution unit 3, and a power supply unit 4.
The input unit 1 includes an input interface 11 and an output interface 12. The input interface 11 is divided into an interface 11a and an interface 11b, wherein the interface 11a is connected with one port of the cable core to be tested, and the interface 11b is connected with the grounding network. The output interface 12 is connected to the control unit 2.
Preferably, in the present invention, a bridge rectifier block 13 is provided in the input unit 1, and the input port 11 is connected to the input port of the bridge rectifier block 13, and the output port of the bridge rectifier block 13 is connected to the output port 12. Thus, the input interface 11 detects the voltage between the cable core to be tested and the grounding grid, and the voltage is transmitted to the control unit 2 through the output interface 12 after passing through the bridge rectifier 13.
The control unit 2 includes an input module 21, an output module 22, and a power module 23. The input module 21 is connected to the output interface 12 of the input unit 1, and is configured to receive the voltage value detected in the input unit 1. The output module 22 is connected to the execution unit 3, and controls the execution unit 3 to operate according to the detected voltage value. The power module 23 is connected to the power supply unit 4 to obtain electric power. Wherein, a preset voltage value is set in the control unit 2 for comparing with the detected voltage value, thereby controlling the action of the execution unit 3.
The execution unit 3 comprises a working loop 31 and an alarm loop 32. When the voltage value between the interface 11a and the interface 11b in the input interface 11 is lower than the preset voltage value, the control unit 3 controls the working circuit 31 to form a closed loop; when the voltage value between the interface 11a and the interface 11b in the input interface 11 is higher than the preset voltage value, the control unit 3 controls the alarm circuit 32 to form a closed loop circuit.
And the power supply unit 4 comprises a power supply 41 and a first switch 42 and is used for carrying out power supply operation on the control unit 2 and the execution unit 3. In the present embodiment, the power source 41 is a rechargeable lithium battery.
The working circuit 31, including the second switch 311, the third switch 312, the time relay, the intermediate relay, and the power source 41 and the first switch 42 in the power supply unit 4. The second switch 311 is connected to the control unit 2, and is controlled by the output module 22 to be turned on or off.
Wherein the coil 3131 in the time relay is connected in parallel with the contact 3132 and is located downstream of the third switch 312, the coil 3141 in the intermediate relay is located in the working circuit 31 and is connected in series with the contact 3132 of the time relay, and the contact 3142 in the intermediate relay is located between the interface 11a and the interface 11b in the input interface 11 and is connected in parallel with the bridge rectifier block 13. At this time, the second switch 311, the third switch 312, the coil 3131, and the power source 41 and the first switch 42 form one circuit loop. The second switch 311, the third switch 312, the contact 3132 in the time relay, the contact 3142 in the intermediate relay, and the power source 41 and the first switch 42 form another circuit loop.
At this time, if the first switch 42, the second switch 311 and the third switch 312 are in the closed state at the same time, the coil 3131 in the time relay is powered on first, and after a certain time delay, the contact 3132 in the time relay is closed, and then the coil 3141 in the intermediate relay is powered on to close the contact 3142 in the intermediate relay, so that the interface 11a and the interface 11b in the input interface 11 are communicated, that is, the cable core to be tested and the ground grid are directly communicated through the contact 3142 in the intermediate relay.
Further, a first buzzer 315 is provided in the work circuit 31 and connected in parallel to the coil 3141 of the intermediate relay. When the coil 3141 in the intermediate relay is energized, the first buzzer 315 is simultaneously energized and emits a discontinuous hum.
The alarm circuit 32, in turn, comprises a fourth switch 321, a second buzzer 322, as well as the power source 41 and the first switch 42 in the power supply unit 4. The fourth switch 321 is connected to the control unit 2, and is controlled by the output module 22 to be turned on or off. When the alarm loop 32 forms a closed loop, the second buzzer 322 is energized and emits a continuous hum.
In addition, in the present invention, an overvoltage protection relay is selected as the control unit 2. Like this, through the overvoltage protection relay, not only can carry out comparative analysis to the voltage value that detects with predetermineeing the voltage value to according to the result of comparison can the closure of direct control second switch 311 and fourth switch 321, but also can adjust predetermineeing the voltage value according to actual conditions, thereby satisfy the demand of different operating modes.
In addition, in the present embodiment, the second switch 311 is set to the normally closed state in advance, and the fourth switch 321 is set to the normally open state. In this way, when the comparison result of the control unit 2 on the input voltage value and the preset voltage value is that the input voltage value is smaller than the preset voltage value, the second switch 311 maintains the closed state, and the fourth switch 321 maintains the open state; when the comparison result of the control unit 2 on the input voltage value and the preset voltage value is that the input voltage value is greater than the preset voltage value, the second switch 311 is switched to the open state, and the fourth switch 321 is switched to the closed state.
Further, in the present embodiment, the input unit 1, the control unit 2, the execution unit 3, and the power supply unit 4 may be integrated into one control box. Therefore, the portable and convenient carrying and use can protect all the components and avoid damage.
Referring to fig. 4, the line calibration auxiliary device of the present invention further includes an external meter pen 5. The external connection meter pen 5 comprises a meter needle 51 and a pen container 52, wherein the pen container 52 is of a hollow structure and is made of insulating materials, the meter needle 51 is located inside the pen container 52 and is made of metal conductive materials, the front end of the meter needle extends out of the pen container 52, and the tail end of the meter needle is connected with an interface 11a in the input interface 11. Thus, the operator can quickly and accurately connect with the port of the cable core to be tested by holding the external meter pen 5 with the meter pointer 51, thereby completing the connection between the interface 11a and the port of the cable core to be tested.
Preferably, the third switch 312 of the working circuit 31 is located inside the barrel 52, and a return spring 53 is provided between the pointer 51 and the third switch 312. At this time, when the hand 51 is in contact with the port of the cable core to be tested and performs the retracting movement in the axial direction of the barrel 52 by the external force, the hand 51 is in contact with the third switch 312, thereby triggering the third switch 312 to switch to the closed state. Therefore, when the pointer 51 contacts with the port of the cable core to be tested, the third switch 312 in the working circuit 31 is closed at the same time, so that the time relay 314 can directly enter the working state, the automation of the control of the working circuit 31 is improved, and the working circuit 31 forms a closed circuit only after the stylus 5 is stably contacted with the cable core to be tested, thereby ensuring the controllability and the safety of the operation process.
Further, in the present embodiment, the hand 51 is designed in a cross-shaped configuration to facilitate connection with the return spring 53. In addition, the pen barrel 52 is designed to be a split structure, and a threaded connection is adopted, so that the third switch 312 and the pen barrel 52 can be fixedly installed.
With reference to fig. 3, 4 and 5, the process of performing the auxiliary cable calibration operation on the cable core by using the auxiliary cable calibration device of the present invention is as follows: first, the interface 11a of the input interface 11 is connected to the tail end of the pointer 51 of the external stylus 5, that is, to the part of the pointer 51 located inside the pen container 52, the interface 11b of the input interface 11 is connected to the ground grid, and the first switch 42 is switched to the closed state. Then, the operator holds the external connection meter pen 5 to fix, so that the front end of the pointer 51 contacts with the port of the cable core to be tested, and the pointer 51 is retracted along the axial direction of the pen barrel 52 to contact with the third switch 312, so that the third switch 312 is switched to the closed state. At this time, the power source 41, the first switch 42, the second switch 311, the third switch 312, and the coil 3131 in the time relay form a closed loop, and the coil 3131 in the time relay enters a delay phase. The delay time of the time relay can be preset and adjusted according to actual conditions. Meanwhile, the voltage value between the cable core to be tested and the grounding grid detected by the pointer 51 and the interface 11b is input into the control unit 2 through the bridge rectifier block 13, and the input voltage value is compared with the preset voltage value in the control unit 2.
If the comparison result is that the input voltage value is lower than the preset voltage value, the second switch 311 maintains the closed state, the fourth switch 321 maintains the open state, and the contact 3132 in the time relay directly enters the closed state after the delay period of the coil 3131 in the time relay is completed. At this time, the power source 41, the first switch 42, the second switch 311, the third switch 312, the contact 3132 in the time relay, and the coil 3141 in the intermediate relay form a closed circuit, the coil 3141 in the intermediate relay is energized, and the contact 3142 in the intermediate relay is closed, so that the lines between the interfaces 11a and 11b are connected. Therefore, the cable core wire to be tested is directly connected with the grounding network, and a wire calibration loop is formed between the cable core wire to be tested and the grounding network, so that subsequent wire calibration test can be carried out. Further, the coil 3141 of the intermediate relay is energized, and the first buzzer 315 is also energized to generate intermittent buzzes, indicating that the cable to be tested can be subjected to a cable calibration operation.
If the comparison result is that the input voltage value is higher than the preset voltage value, the closed states of the second switch 311 and the fourth switch 321 are switched to each other, that is, the second switch 311 is switched to the open state, and the fourth switch 321 is switched to the closed state. In this way, the power source 41, the first switch 42, the fourth switch 321, and the second buzzer 322 form a closed circuit, and the second buzzer 322 is energized to generate continuous buzzes, thereby providing an alarm indicating that the cable to be measured is electrified. At this time, even though the contact 3132 in the time relay enters the closed state under the action of the coil 3131 in the time relay, since the second switch 311 is already in the open state, the intermediate relay is always in the power-off state, i.e., the interface 11a and the interface 11b are in the open state, so that the contact between the cable to be tested and the grounding grid is avoided.
In addition, when the cable core is subjected to auxiliary cable calibration by using the auxiliary cable calibration device of the present invention, a connection manner as shown in fig. 6 may also be adopted, that is, two ends of the cable core to be tested are respectively provided with one auxiliary cable calibration device of the present invention. Like this, if directly be connected electrified cable and grounding net through the universal meter, can avoid taking place the damage to the universal meter to improve the protection to equipment.
Claims (8)
1. The wire calibration auxiliary equipment is characterized by comprising an input unit, a control unit, an execution unit and a power supply unit; wherein the content of the first and second substances,
the input unit comprises an input interface and an output interface; the input interface is divided into two ends, one end of the input interface is connected with one port of the cable core wire to be tested, and the other end of the input interface is connected with the grounding grid; the output interface is connected with the control unit;
the control unit comprises an input module, an output module and a power module, and is provided with a preset voltage value; the input module is connected with an output interface of the input unit, the output module is connected with the execution unit, and the power supply module is connected with the power supply unit;
the execution unit comprises a working loop and an alarm loop; when the voltage value between the two ends of the input interface is lower than a preset voltage value, the control unit controls the working circuit to form a closed loop so that a cable core wire to be tested is connected with a grounding network; when the voltage value between the two ends of the input interface is higher than a preset voltage value, the control unit controls the alarm circuit to form a closed loop circuit to give an alarm prompt;
the power supply unit comprises a power supply and a first switch and is used for supplying power to the control unit and the execution unit;
a bridge rectifying block is arranged in the input unit; the input end of the bridge rectifier block is connected with the input interface, and the output end of the bridge rectifier block is connected with the output interface;
the working circuit comprises a second switch, a third switch, a time relay, an intermediate relay, a power supply and a first switch in the power supply unit; the on-off of the second switch is controlled by an output module in the control unit, a coil of the time relay is connected with a contact in parallel and is positioned at the downstream position of the third switch, a coil of the intermediate relay is connected with the contact of the time relay in series, and the contact of the intermediate relay is positioned between two ends of the input interface in the input unit and is connected with the bridge rectifier block in parallel.
2. The line correction auxiliary apparatus according to claim 1, wherein the work circuit further includes a first hummer connected in parallel with a coil of the intermediate relay.
3. The line correction auxiliary equipment of claim 1, wherein the alarm loop comprises a fourth switch, a second buzzer, and a power source and a first switch in the power supply unit; the on-off of the fourth switch is controlled by an output module in the control unit.
4. The line calibration auxiliary device according to any one of claims 1-3, characterized in that the device further comprises an external meter pen, wherein the external meter pen comprises an insulated pen container and a conductive meter pointer; the pen container is of a hollow structure, and the pointer is positioned inside the pen container; one end of the pointer extends out of the pen container and is in contact with a cable core wire to be tested, and the other end of the pointer is connected with one end of the input interface in the input unit.
5. The line calibration auxiliary device according to claim 4, wherein the second switch is located inside the pen barrel, and the pointer can move axially relative to the pen barrel; when the pointer carries out axial recovery action relative to the pen container, the second switch is touched and switched from an off state to a closed state.
6. The line calibration auxiliary device according to claim 5, wherein a return spring is arranged between the pointer and the second switch and used for pushing the pointer to axially extend along the pen container.
7. The line calibration auxiliary equipment of claim 4, wherein the pen container is in a split structure of threaded connection.
8. The line calibration auxiliary equipment as claimed in any one of claims 1-3, wherein the control unit is an overvoltage protection relay.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710711731.0A CN107525995B (en) | 2017-08-18 | 2017-08-18 | Line calibration auxiliary equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710711731.0A CN107525995B (en) | 2017-08-18 | 2017-08-18 | Line calibration auxiliary equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107525995A CN107525995A (en) | 2017-12-29 |
| CN107525995B true CN107525995B (en) | 2020-01-24 |
Family
ID=60681498
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710711731.0A Active CN107525995B (en) | 2017-08-18 | 2017-08-18 | Line calibration auxiliary equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107525995B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112180292A (en) * | 2020-09-30 | 2021-01-05 | 中国核动力研究设计院 | System and method for detecting on-off of cables between nuclear power plant reactor control system cabinets |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201130213Y (en) * | 2007-11-15 | 2008-10-08 | 广州锐翔电力工程设备有限公司 | High pressure electrification display trigger device for induction high pressure armored cable of electrification state |
| CN202142651U (en) * | 2011-06-28 | 2012-02-08 | 上海梅山钢铁股份有限公司 | Safe grounding device of power cable |
| CN204067617U (en) * | 2014-09-05 | 2014-12-31 | 国家电网公司 | Earthing device |
| CN104505688B (en) * | 2014-12-12 | 2017-02-22 | 国家电网公司 | Operation method and device of grounding wire |
| CN105356084A (en) * | 2015-11-30 | 2016-02-24 | 国网北京市电力公司 | Grounding wire and method using same for live detection |
-
2017
- 2017-08-18 CN CN201710711731.0A patent/CN107525995B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN107525995A (en) | 2017-12-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103617754A (en) | Fault simulation and test simulation system for power cables | |
| CN107525995B (en) | Line calibration auxiliary equipment | |
| CN207067294U (en) | A kind of down conductor continuity test instrument | |
| CN105807187A (en) | Single-phase ground-fault assist detection device | |
| CN202886502U (en) | Leakage protector tester | |
| CN104502815A (en) | Testing device for non-linear resistor type resonance eliminator | |
| CN105445627A (en) | DC system insulation inspection and acceptance instrument | |
| CN203732606U (en) | Insulation parameter measuring device for power grid with neutral point grounded via resistance | |
| CN108181538B (en) | Intelligent short circuit experiment table | |
| CN203705530U (en) | Wireless high voltage electroscope | |
| CN102074927A (en) | Earth leakage protection circuit of withstand voltage tester | |
| CN102419407B (en) | Ground detection experiment system for mining equipment | |
| CN201852920U (en) | Loop resistance test pliers head of handcart switch | |
| CN204731374U (en) | The discharging detection device of ignition coil | |
| JP4441720B2 (en) | Failure point search device | |
| CN204142887U (en) | Wireless remote control type instrument for testing polarity of current transformer | |
| CN106896335A (en) | A kind of portable thread line fault indicator tester | |
| CN108761373B (en) | Tester | |
| CN204008859U (en) | Distribution system checkout equipment | |
| CN202600093U (en) | DC earthing point detector for electrical network line | |
| CN202083766U (en) | High voltage grounding line selection apparatus | |
| CN107167756B (en) | Main loop guide rod for sleeve type rheological test | |
| CN205594127U (en) | Many functional test of electrovacuum pipe equipment | |
| CN214174474U (en) | Direct current high voltage generator, direct current high voltage generator assembly and control system | |
| CN211402676U (en) | Ground fault point inspection system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |