CN210894653U - Current transformer polarity measuring device - Google Patents
Current transformer polarity measuring device Download PDFInfo
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- CN210894653U CN210894653U CN201921387081.XU CN201921387081U CN210894653U CN 210894653 U CN210894653 U CN 210894653U CN 201921387081 U CN201921387081 U CN 201921387081U CN 210894653 U CN210894653 U CN 210894653U
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Abstract
The utility model relates to the field of polarity measurement of current transformers, in particular to a current transformer polarity measurement device, which comprises a device body, an external primary test wire hook and an external secondary test wire, wherein the device body comprises a power module, a polarity indication module and a primary pressurization control module; the primary pressurization control module is connected with the primary side of the current transformer through a primary test wire hook, controls the voltage output of the power supply module and performs primary pressurization on the current transformer; the polarity indication module is connected with the secondary side of the current transformer through a secondary test line and used for measuring current and indicating polarity. This device improves a pressurization mode, need not climb and carry out a pressurization, only needs alone can accomplish current transformer polarity measurement operation, and convenient and fast has reduced the safe risk simultaneously, uses manpower sparingly and materials, has considerable economic benefits.
Description
Technical Field
The utility model relates to a current transformer's polarity measurement field especially relates to a current transformer polarity measuring device.
Background
The current transformer comprises a primary side wire inlet end P1, a primary side wire outlet end P2, a secondary side head end S1 and a secondary side tail end S2, the four ports are respectively connected with corresponding lines, however, the situation that the line polarities of S1 and S2 are reversed can occur during wiring, the direction of the measured current is reversed, protection misoperation, instrument damage and the like are caused, and therefore polarity test is required to be carried out to protect the correctness of the polarity of the current transformer.
At present, three methods are mainly adopted for testing the polarity of a Current Transformer (CT), namely a direct current method, an alternating current method and an instrument method, wherein the direct current method is widely adopted for testing the polarity of the CT with the advantages of simplicity, safety and accuracy. However, the method has many problems in practical application, firstly, the equipment used in the test needs to be temporarily raised by the tester, including the materials such as a storage battery, an experimental line, a pointer microammeter, a lap joint rod and the like, and the preparation of the materials is time-consuming and labor-consuming; secondly there is randomness, instability and operation inconvenience in the construction of equipment, for example it is fixed with the battery to pull for the insulating tape for the experiment line usually, pulls in the test and destroys the stability of connection easily, and simultaneously, the difficult operation of being connected of experiment line and both sides and the personnel's demand is more in the test process, and has the cooperation problem. Particularly, when outdoor CT with high voltage level and high framework is measured, the difficulty of one-time pressurization is high, the framework needs to be climbed by an insulating ladder for pressurization, and the method has high personal and equipment safety risks. Moreover, two groups of personnel are needed for operation, one group of personnel applies impact voltage to the primary side by a dry battery, the other group of personnel measures on the secondary side by a pointer microammeter, and the polarity of the CT is judged according to the primary pressurizing direction and the pointer deflection direction of the secondary microammeter.
SUMMERY OF THE UTILITY MODEL
The utility model provides a current transformer polarity measuring device improves a pressurization mode, makes operating personnel avoid climbing the framework of eminence and once pressurize to realized polarity indicating device and voltage generating device's integration, only need alone can accomplish current transformer polarity measurement operation, greatly reduced current transformer polarity measurement work's personal and equipment safety risk, reduced consumeing of manpower and materials, had considerable economic benefits.
In order to achieve the above purpose, the utility model provides a following technical scheme:
a polarity measuring device of a current transformer comprises a device body, and an external primary test wire hook and an external secondary test wire, wherein the device body comprises a power supply module, a polarity indicating module and a primary pressurization control module;
the power supply module is electrically connected with the primary pressurization control module, the primary pressurization control module is connected with the primary test wire hook, the other end of the primary test wire hook is connected with the primary side of the current transformer, the primary pressurization control module controls the voltage output of the power supply module and performs primary pressurization on the current transformer through the primary test wire hook;
the polarity indication module is connected with the secondary test wire, the other end of the secondary test wire is connected with the secondary side of the current transformer, and the polarity indication module measures current of the current transformer through the secondary test wire and indicates polarity.
The measuring device is integrated, the power supply is pressurized and the polarity is displayed in one device, and the polarity measuring work of the current transformer can be completed by only one person, so that the consumption of manpower and material resources is reduced; and through the quick hook joint of the primary side of primary test wire hook and current transformer, secondary test wire and the secondary side grafting of current transformer, improved once the pressurization mode, make operating personnel avoid climbing the framework of eminence and carry out once pressurization, greatly reduced the people's body and the equipment safety risk of current transformer polarity measurement work.
Furthermore, the power module is formed by connecting a plurality of rechargeable storage batteries in series. The storage battery controls output voltage through the primary pressurization control module to pressurize the current transformer for one time, and the primary pressurization control module can adjust the output voltage of the storage battery according to the polarity indication condition of the polarity indication module.
Further, the polarity indication module is provided with a mA terminal and a com terminal, and the mA terminal and the com terminal are respectively connected with the secondary test wire.
Further, the polarity indication module is provided with a milliampere dial for indicating the polarity of the current transformer.
The polarity indication module is the same as the deflection principle of the milliammeter, when current flows in from the mA terminal and flows out from the com terminal, the pointer of the milliammeter dial is positively deflected, otherwise, the pointer is reversely deflected, and the polarity of the current transformer can be measured by analyzing the primary pressurization condition and the secondary pointer deflection condition.
Further, the primary pressurizing control module is provided with a positive terminal and a negative terminal, and the positive terminal and the negative terminal are respectively connected with the primary test wire hook. The primary test wire hook connected with the positive terminal is hooked with a primary side wire inlet end of the current transformer, and the primary test wire hook connected with the negative terminal is hooked with a primary side wire outlet end of the current transformer.
Further, the positive terminal is electrically connected with the positive electrode of the power module in the device body, and the negative terminal is electrically connected with the negative electrode of the power module in the device body. The power supply module is used for outputting voltage to the current transformer through the positive terminal and the negative terminal to pressurize the current transformer.
Further, the primary pressurization control module is provided with an indicator light and a primary pressurization control switch, and the indicator light and the primary pressurization control switch are connected in series in a circuit in which the negative terminal is connected with the negative electrode of the power module. The pilot lamp is used for indicating whether power module has the switch-on, once pressurize the control switch and have different gears, its output voltage that can control power module's terminal, select different gears for use according to current transformer's transformation ratio, when current transformer becomes than little, select for use the voltage pressurization of less gear, when current transformer transformation ratio is great, select for use the voltage pressurization of great gear, if polarity indication module's pointer deflects unobviously, then current transformer's the primary side need add bigger voltage, it is obvious that the pointer just can make the deflection at the secondary side formation bigger electric current, judge current transformer's polarity better, it is more accurate to make its measurement.
Furthermore, the primary test wire hook comprises a telescopic insulating rod and a wire hook arranged at the top of the telescopic insulating rod, the wire hook is hooked with the primary side of the current transformer, the wire hook is connected with a primary test wire, the other end of the primary test wire is provided with a primary wiring terminal, and the primary wiring terminal is connected with the primary pressurization control module.
The line hook through flexible insulator spindle top and current transformer's once side hook joint, the line hook passes through the terminal and is connected with a pressurization control module, and the swift simple of plugging into, the adjustable flexible length of flexible insulator spindle simultaneously makes operating personnel avoid climbing the framework of eminence and carry out pressurization once, greatly reduced current transformer polarity measurement work personal and equipment safety risk.
Further, the bottom of flexible insulator spindle is equipped with insulating handle, insulating handle is equipped with spacing rubber circle. The insulating handle and the limiting rubber ring are made of insulating materials with good insulating property, so that the operating personnel can be protected from being injured by induction electricity, and the personal safety of the measuring personnel is well guaranteed.
Further, secondary wiring terminals are arranged at two ends of the secondary test line, one end of each secondary wiring terminal is connected with the secondary side of the current transformer, and the other end of each secondary wiring terminal is connected with the polarity indication module. The secondary test wire with enough length is used, one end of the secondary test wire is connected with the secondary side leading-out end of the current transformer through the wiring terminal, the other end of the secondary test wire is connected with the polarity indication module, and the secondary test wire is convenient and quick and is reliable in connection.
The utility model has the advantages that:
1. the integrated measuring device solves the problem that the preparation of materials is time-consuming and labor-consuming due to the temporary arrangement of testers during the traditional test, wherein the materials comprise a storage battery, an experimental wire, a pointer type microammeter, a lap joint rod, an insulating ladder and the like;
2. the randomness and the instability of the construction of equipment in the traditional test are overcome, the internal wiring of the device is reliable and is not easy to loosen, the external connection is good, and the contact is reliable;
3. the primary pressurizing mode is improved, so that an operator is prevented from climbing a high-rise framework to perform primary pressurizing, and the personal and equipment safety risks of the polarity measurement work of the current transformer are greatly reduced;
4. the polarity measuring device has the advantages that the operation is convenient, the cooperation is not needed, the integration of the polarity indicating device and the voltage generating device is realized, the polarity measuring work of the current transformer can be completed only by one person, the consumption of manpower and material resources is reduced, and considerable economic benefits are realized.
Drawings
Fig. 1 is a schematic view of the overall structure of the present invention;
FIG. 2 is a schematic view of the structure of the device body;
FIG. 3 is a schematic view of a primary test wire hook;
FIG. 4 is a schematic structural diagram of a quadratic test line;
FIG. 5 is a schematic diagram of the present apparatus for measuring the polarity of a current transformer;
in the figure: 1-device body, 11-power module, 12-polarity indication module, 13-primary pressurization control module, 14-indicator light, 15-primary pressurization control switch, 2-primary test wire hook, 21-telescopic insulating rod, 22-wire hook, 23-primary test wire, 24-primary binding post, 25-insulating handle, 3-secondary test wire and 31-secondary binding post.
Detailed Description
The drawings are for illustrative purposes only and are not to be construed as limiting the patent; for the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted. The positional relationships depicted in the drawings are for illustrative purposes only and are not to be construed as limiting the present patent.
Example 1:
as shown in fig. 1 and 2, a polarity measuring device for a current transformer includes a device body 1, and an external primary test wire hook 2 and an external secondary test wire 3, where the device body 1 includes a power module 11, a polarity indication module 12, and a primary pressurization control module 13;
the power module 11 is formed by connecting a plurality of rechargeable storage batteries in series, the power module 11 is electrically connected with the primary pressurization control module 13, the primary pressurization control module 13 is connected with the primary test wire hook 2, the other end of the primary test wire hook 2 is connected with the primary side of the current transformer, the primary pressurization control module 13 controls the voltage output of the power module 11, and the current transformer is pressurized once through the primary test wire hook 2;
the polarity indication module 12 is connected with the secondary test line 3, the other end of the secondary test line 3 is connected with the secondary side of the current transformer, and the polarity indication module 12 measures the current of the current transformer through the secondary test line 3 and indicates the polarity.
In this embodiment, the polarity indication module 12 is provided with a mA terminal and a com terminal, and is further provided with a mA dial, the mA terminal and the com terminal are respectively connected to the secondary test line 3, the polarity indication module 12 has the same deflection principle as the mA meter, when a current flows in from the mA terminal and flows out from the com terminal, a pointer of the mA dial is positively deflected, otherwise, the pointer is reversely deflected, and the polarity of the current transformer can be measured by analyzing a primary pressurization condition and a secondary pointer deflection condition.
In this embodiment, the primary pressurizing control module 13 is provided with a positive terminal and a negative terminal, the positive terminal and the negative terminal are respectively connected with the primary test wire hook 2, the positive terminal is electrically connected with the positive pole of the power module 11 inside the device body 1, the negative terminal is electrically connected with the negative pole of the power module 11 inside the device body 1, the negative terminal is further connected with an indicator lamp 14 and a primary pressurizing control switch 15 in series in a circuit connected with the negative pole of the power module 11, the indicator lamp 14 is used for indicating whether the power module 11 is switched on, the primary pressurizing control switch 15 has different gears including "off", "KK 1" and "KK 2", when the control switch is "off", the positive and negative terminals of the device have no voltage output, when the control switch is "KK 1", the positive and negative terminals of the device output larger voltage, when the control switch is "KK 2", the positive and negative terminals of the device output smaller voltages. Select different gears according to current transformer's transformation ratio for use, when current transformer become than less, select for use the voltage pressurization of "KK 2" gear, when current transformer transformation ratio is great, select for use the voltage pressurization of "KK 1" gear, if the pointer deflection of polarity indication module 12 is not obvious, then current transformer's once side need add bigger voltage, it is obvious that the pointer deflection just can be made to the bigger electric current of secondary side formation, judge current transformer's polarity better, make its measurement more accurate.
As shown in fig. 3, the primary test wire hook 2 includes a telescopic insulating rod 21 and a wire hook 22 fixed on the top thereof, the wire hook 22 is connected with a primary test wire 23, and the other end of the primary test wire 23 is provided with a primary binding post 24. The wire hook 22 of one primary test wire hook 2 is hooked with a primary side wire inlet end of the current transformer, and the primary terminal 24 is inserted into a positive terminal of the primary pressurization control module 13; the wire hook 22 of the other primary test wire hook 2 is hooked with a primary side wire outlet end of the current transformer, and the primary terminal 24 is plugged with a negative terminal of the primary pressurization control module 13. Wire hook 22 through flexible insulator spindle 21 top and current transformer's the side hook joint, wire hook 22 can hook current transformer's inlet wire end, the screw hole on the leading-out terminal wiring board, can reliably connect, the contact is good, wire hook 22 is connected with pressurization control module 13 once through the terminal, it is swift simple to plug into, the adjustable flexible length of flexible insulator spindle 21 simultaneously, make operating personnel avoid climbing the framework of eminence and carry out pressurization once, greatly reduced current transformer polarity measurement work's personal and equipment safety risk.
Wherein, the bottom of flexible insulator spindle 21 is equipped with insulating handle 25, and insulating handle 25 is equipped with spacing rubber circle, and insulating handle 25 and spacing rubber circle adopt the insulating material preparation that insulating properties is good to form, can protect operating personnel not receive the induction electricity injury, fine guarantee measuring staff's personal safety.
As shown in fig. 4, the two ends of the secondary test line 3 are provided with secondary terminals 31; one end of a secondary wiring terminal 31 of one secondary test wire 3 is in plug connection with the head end of the secondary side of the current transformer, and the other end of the secondary wiring terminal 31 is in plug connection with a mA terminal of the polarity indication module 12; one end of a secondary terminal 31 of the other secondary test line 3 is in plug connection with the secondary side tail end of the current transformer, and the other end of the secondary terminal 31 is in plug connection with the com terminal of the polarity indication module 12. The secondary test wire 3 with enough length is used, one end of the secondary test wire is connected with the secondary side of the current transformer through a binding post, and the other end of the secondary test wire is connected with the polarity indication module 12, so that the secondary test wire is convenient and quick to use and reliable in connection.
As shown in fig. 5, the current transformer includes a primary side wire inlet end P1, a primary side wire outlet end P2, a secondary side head end S1 and a secondary side tail end S2, and the four ports are respectively connected to corresponding lines;
the power module 11 is formed by connecting six rechargeable storage batteries B1-B6 in series, and each storage battery is 2V;
the polarity indication module 12 is a milliammeter which is provided with a mA terminal, a com terminal and a milliammeter dial;
the primary pressurization control module 13 is connected in series on a power supply loop of the power module 11, the primary pressurization control module 13 comprises a plus terminal, a minus terminal, an indicator light and a control switch, the plus terminal is connected with the positive pole of the storage battery, the minus terminal is connected with the indicator light and the control switch in series and is connected with the negative pole of the storage battery, the control switch has three gears, namely 'off', 'KK 1' and 'KK 2', when the switch is 'off', no voltage is output from the plus and minus terminals of the device, when the switch is 'KK 1', the plus and minus terminals of the device output 12V voltage, and when the switch is 'KK 2', the plus and minus terminals of the device output 6V voltage. Different gears are selected for use according to current transformer's transformation ratio, become when the comparison hour when current transformer, select for use "KK 2" position measurement, when current transformer transformation ratio is great, select for use "KK 2" position measurement, polarity indication table pointer deflects unobviously, once need add bigger voltage, form bigger electric current at the secondary and just enable the pointer deflection obvious.
When testing polarity, the mA terminal is inserted through the secondary side head end S1 of the current transformer of the secondary terminal 31 of the secondary test wire 3, the com terminal is inserted through the secondary terminal 31 of the secondary test wire 3 and the secondary side head end S2 of the current transformer, the plus terminal is inserted with the primary terminal 24 of the primary test wire hook 2, the wire hook 22 of the primary test wire hook 2 is hooked on the screw hole on the primary side inlet wire end P1 wiring board of the current transformer through the telescopic insulating rod 21, the minus terminal is inserted with the primary terminal 24 of the primary test wire hook 2, the wire hook 22 of the primary test wire hook 2 is hooked on the screw hole on the primary side inlet wire end P2 wiring board of the current transformer through the telescopic insulating rod 21, testing can be carried out after connecting wires, and voltage output of different gears is selected according to the tested current transformer, make control switch arrange in "KK 1" or "KK 2", observe the milliampere dial plate pointer of milliampere meter and deflect and can judge current transformer's polarity, after finishing using, arrange control switch in "disconnection" and can stop once pressurizeing to take in once taking down test wire hook 2 and secondary test wire 3, so that use next time.
The utility model integrates the measuring device, collects the power source to pressurize and display the polarity in one device, and only one person is needed to complete the polarity measuring work of the current transformer, thereby reducing the consumption of manpower and material resources; and through the primary test wire hook 2 with the primary side of current transformer fast hook-up be connected, secondary test wire 3 with current transformer's secondary side peg graft, improved once the pressurization mode, make operating personnel avoid climbing the framework of eminence and carry out once pressurization, greatly reduced current transformer polarity measurement work personal and equipment safety risk.
It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not limitations to the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (10)
1. A polarity measuring device of a current transformer is characterized by comprising a device body, and an external primary test wire hook and an external secondary test wire, wherein the device body comprises a power supply module, a polarity indicating module and a primary pressurization control module;
the power supply module is electrically connected with the primary pressurization control module, the primary pressurization control module is connected with the primary test wire hook, the other end of the primary test wire hook is connected with the primary side of the current transformer, the primary pressurization control module controls the voltage output of the power supply module and performs primary pressurization on the current transformer through the primary test wire hook;
the polarity indication module is connected with the secondary test wire, the other end of the secondary test wire is connected with the secondary side of the current transformer, and the polarity indication module measures current of the current transformer through the secondary test wire and indicates polarity.
2. The polarity measuring device of claim 1, wherein said power module comprises a plurality of rechargeable batteries connected in series.
3. The polarity measuring device of claim 1, wherein said polarity indicating module is provided with a mA terminal and a com terminal, and said mA terminal and said com terminal are respectively connected with said secondary test line.
4. The polarity measuring device of claim 1, wherein the polarity indicating module is provided with a milliamp dial for indicating the polarity of the current transformer.
5. The polarity measuring device of claim 1, wherein the primary pressurizing control module is provided with a positive terminal and a negative terminal, and the positive terminal and the negative terminal are respectively connected with the primary test wire hook.
6. The polarity measuring device of claim 5, wherein said positive terminal is electrically connected to the positive terminal of said power module inside said device body, and said negative terminal is electrically connected to the negative terminal of said power module inside said device body.
7. The polarity measuring device of claim 6, wherein the primary pressurizing control module is provided with an indicator light and a primary pressurizing control switch, and the indicator light and the primary pressurizing control switch are connected in series in a circuit in which the negative terminal is connected with the negative electrode of the power supply module.
8. The polarity measuring device of claim 1, wherein the primary test wire hook comprises a telescopic insulating rod and a wire hook arranged on the top of the telescopic insulating rod, the wire hook is hooked with the primary side of the current transformer, a primary test wire is connected to the wire hook, a primary terminal is arranged at the other end of the primary test wire, and the primary terminal is connected with the primary pressurization control module.
9. The polarity measuring device of claim 8, wherein an insulating handle is arranged at the bottom of the telescopic insulating rod, and the insulating handle is provided with a limiting rubber ring.
10. The polarity measuring device of claim 1, wherein the secondary terminals are disposed at two ends of the secondary test line, the secondary terminal at one end is connected to the secondary side of the current transformer, and the secondary terminal at the other end is connected to the polarity indication module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921387081.XU CN210894653U (en) | 2019-08-23 | 2019-08-23 | Current transformer polarity measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921387081.XU CN210894653U (en) | 2019-08-23 | 2019-08-23 | Current transformer polarity measuring device |
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| CN210894653U true CN210894653U (en) | 2020-06-30 |
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| CN201921387081.XU Active CN210894653U (en) | 2019-08-23 | 2019-08-23 | Current transformer polarity measuring device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110389280A (en) * | 2019-08-23 | 2019-10-29 | 广东电网有限责任公司 | A kind of current transformer polarity measurement device |
| CN114167318A (en) * | 2021-11-09 | 2022-03-11 | 广西电网有限责任公司柳州供电局 | Current transformer wireless polarity judgment device and method capable of supplying power to negative control terminal |
-
2019
- 2019-08-23 CN CN201921387081.XU patent/CN210894653U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110389280A (en) * | 2019-08-23 | 2019-10-29 | 广东电网有限责任公司 | A kind of current transformer polarity measurement device |
| CN114167318A (en) * | 2021-11-09 | 2022-03-11 | 广西电网有限责任公司柳州供电局 | Current transformer wireless polarity judgment device and method capable of supplying power to negative control terminal |
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