CN100432680C - Forcipated mutual-inductor, forcipated ammeter and verification method of forcipated ammeter - Google Patents
Forcipated mutual-inductor, forcipated ammeter and verification method of forcipated ammeter Download PDFInfo
- Publication number
- CN100432680C CN100432680C CNB2005100366752A CN200510036675A CN100432680C CN 100432680 C CN100432680 C CN 100432680C CN B2005100366752 A CNB2005100366752 A CN B2005100366752A CN 200510036675 A CN200510036675 A CN 200510036675A CN 100432680 C CN100432680 C CN 100432680C
- Authority
- CN
- China
- Prior art keywords
- coil
- iron core
- clamp
- amperemeter
- sampling thief
- 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
Landscapes
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
Abstract
The invention relates to a split-core transformer and a split-core current meter, and relative self correct method of split-core current meter, wherein said split-core transformer comprises frame, iron core, detecting coil on the iron core, and correcting coil induced with detecting coil; the iron core can be separated into two semi bodies; said frame also comprises a device for controlling the combination and separation of two semi bodies; the split-core current meter has said split-core transformer and relative auxiliary circuit. Since it uses correcting coil, the split-core transformer and split-core current meter can pre-correct the error before detection.
Description
Technical field
The present invention relates to a kind of device that is used to measure curtage, particularly a kind of clamp on amperemeter that is used to measure electric current.
Background technology
Measure electric current and generally adopt conventional current surveying instruments such as amp gauge, multimeter, be connected in series to this type of current measurement instrument in the circuit after, can directly draw the size of current of respective branch.Yet, if continue to use this traditional current measuring method in high pressure occasion (for example measuring electric current in the high-tension bus-bar or the like), then have following 2 weak points at least: the first, must insert current measurement instrument earlier with the dump of circuit under test, and then energized, not only process is loaded down with trivial details, and needs outage, and this can cause very big puzzlement for utility network, because frequent the power failure not only makes troubles to residential electricity consumption, and causes very big loss can for factory, office; The second, during with the electric current in this class methods measurement high-tension bus-bar, danger coefficient is bigger, and especially when tester's disconnection or energized, instantaneous pressure changes may cause instrument damage even casualties.In order to address the above problem, industry is developed clamp on amperemeter.Clamp on amperemeter is a kind of device that is used to measure size of current, is characterized in utilizing electromagnetic induction to carry out current measurement under the situation of deenergization not.The ultimate principle of clamp on amperemeter is disclosed among Fig. 1 of CN2125144U number Chinese utility model patent: by the inductive coil on iron core the alternating current on the tested lead is converted into ac voltage signal, shows measurement result through promoting gauge outfit behind the diode detection.Though present clamp on amperemeter has been abandoned the mode of analogue measurement, demonstration gradually, begin to adopt the exact figure method of sampling more, and it is when display result, adopted advanced more technology such as digital demonstration, but still basic identical on the principle with the mutual inductance principle that CN2125144U number Chinese utility model patent disclosed.
Yet, there is the not high enough problem of precision in clamp on amperemeter, the measuring error of existing clamp on amperemeter is generally all more than 0.2%, and this error is through the result of fine adjustment when dispatching from the factory, in the application scenario of reality, the aging further increase that all can cause measuring error of the influence of test environment and clamp on amperemeter self, thus cause very big error for the electric energy metrical of country.Industry has also been done a lot of improvement at clamp on amperemeter, tries hard to reduce its measuring error.For example CN2412283Y number Chinese utility model patent discloses a kind of by changing the technical scheme that the jaw volume improves the clamp on amperemeter precision; CN2518111Y number Chinese utility model patent discloses a kind of by increasing the scheme that function shelves number improves the clamp on amperemeter precision.Though the measuring accuracy of clamp on amperemeter has been optimized in above-mentioned these improvement to a certain extent, but still unresolved root problem: clamp on amperemeter in use for some time, the jaw junction deforms most probably, gets rusty, thereby cause jaw in conjunction with not tight, cause magnetic loop to be obstructed, and make a general survey of existing clamp on amperemeter, before measuring, all can't carry out error compensation above-mentioned unfavorable factor, that is, existing clamp on amperemeter does not all possess self-tuning function.
Summary of the invention
First purpose of the present invention provides a kind of forcipated mutual-inductor, and it can combine with auxiliary circuit and possess self-correcting function.
Second purpose of the present invention provides a kind of clamp on amperemeter that possesses self-correcting function;
Another object of the present invention provides a kind of automatic correcting method of clamp on amperemeter.
For achieving the above object, the forcipated mutual-inductor that provides of the present invention comprises housing, is contained in iron core in the housing, is arranged on magnetic test coil and correcting coil on the iron core.By combining of auxiliary circuit and correcting coil, can make correction to the error of mutual inductor.
The clamp on amperemeter that the present invention provides comprises forcipated mutual-inductor and auxiliary circuit, and forcipated mutual-inductor comprises housing, be contained in iron core in the housing, be arranged on magnetic test coil and correcting coil on the iron core.By combining of auxiliary circuit and correcting coil, can make correction to the error of clamp on amperemeter.
The clamp on amperemeter automatic correcting method that the present invention provides is to adopt a correcting coil, by with the combining of auxiliary circuit, can proofread and correct the error of clamp on amperemeter.
The forcipated mutual-inductor that the present invention provides, clamp on amperemeter and clamp on amperemeter automatic correcting method have all adopted correcting coil, can carry out self-correcting before test, and then carry out error compensation.Concrete structure, method are embodied in the embodiment described later.
Description of drawings
Fig. 1 is the structural representation of forcipated mutual-inductor;
Fig. 2 is the synoptic diagram of clamp on amperemeter under correcting state;
Fig. 3 is the synoptic diagram of clamp on amperemeter under the measurement state;
Fig. 4 is the structural representation of another embodiment of clamp on amperemeter;
Fig. 5 is the schematic block diagram of clamp on amperemeter automatic correcting method.
Be described further below in conjunction with each embodiment and accompanying drawing thereof.
Embodiment
Referring to shown in Figure 1, forcipated mutual-inductor 1 of the present invention comprises housing 11, be contained in iron core 12 in the housing 11, be arranged on magnetic test coil 13 and correcting coil 14 on the iron core 12.
Fig. 2 is the structural representation of clamp on amperemeter 3 of the present invention.Clamp on amperemeter 3 is made up of forcipated mutual-inductor 1 and auxiliary circuit 2.All circuit among Fig. 2 in the frame of broken lines all can be regarded auxiliary circuit 2 as.The effect of auxiliary circuit 2 is that the error of forcipated mutual-inductor 1 is proofreaied and correct in advance, and is combined into the clamp on amperemeter 3 with current measurement function with forcipated mutual-inductor 1.
Auxiliary circuit 2 comprises four parts: proofread and correct branch road, detection branch, digital signal processing unit and input-output device.The AD sampling thief 23 of proofread and correct V/I (voltage/current) converter 21 that branch road comprises adjustable signal generator 20, connects with adjustable signal generator 20, I/V (current/voltage) converter 22, connecting with I/V converter 22, correcting coil 14 is series between V/I converter 21 and the I/V converter 22; Detection branch comprises I/V converter 25 and is series at the A/D sampling thief 26 of I/V converter 25 1 ends that the other end of I/V converter 25 is connected with magnetic test coil 13.
Digital signal processing unit in the present embodiment can be DSP (digital signal processing) chip 24 that possesses calculating and control ability, and input-output device can be keyboard 27 and LCD 28.The sampled signal of A/D sampling thief 23 and A/D sampling thief 26 all is input in the dsp chip 24, after handling through dsp chip 24, demonstrates corresponding results on LCD 28, and keyboard 27 can carry out corresponding operating to data.
Clamp on amperemeter 3 of the present invention can carry out error correction before test voltage, its principle of work is as follows: Closing Switch 29 and iron core 12 (left halfbody 120 and right halfbody 121 closures), proofread and correct branch road and be in conducting state this moment.Produce a normal voltage signal by adjustable signal generator 20, this voltage signal converts normalized current I to through V/I converter 21
1, normalized current I
1Flow through correcting coil 14 and make and produce the mutual inductance electric current I in the magnetic test coil 13 by mutual inductance
2, normalized current I
1With the mutual inductance electric current I
2Through converting voltage signal again to behind I/V converter 22, the I/V converter 25, carry out signal sampling through A/D sampling thief 23 and A/D sampling 26 respectively more respectively, sampled result is U
1, U
2, U
1, U
2All be input in the dsp chip 24 and compare.Suppose that magnetic test coil 13 is identical with the number of turn of correcting coil 14 in the present embodiment, then the comparative result of dsp chip 24 should be U in theory
1=U
2, still, because U
1Be original signal, its loss and error are less; U
2System obtains through the excess current mutual inductance, the left halfbody 120 of iron core 12 and right halfbody 121 in conjunction with prerequisites such as undertighten under, may have bigger error, cause U
1≠ U
2, therefore, in order to proofread and correct this error, dsp chip 24 will be at U
2On multiply by a correction coefficient P (P may be greater than 1, also may less than 1), make U
1=PU
2, dsp chip 24 is stored to inner storer with correction coefficient P, controls the information that LCD 28 shows " calibrated finishing " and so on then.Certainly, above-mentioned trimming process can repeat repeatedly the back correction coefficient P is averaged, to reach the purpose that reduces error.
In conjunction with shown in Figure 3, through after the correction of above-mentioned steps, cut off switch 29, make that proofreading and correct branch road disconnects, clamp on amperemeter 3 advances the measurement state.Operating grip 110 makes the left halfbody 120 of iron core 12 and right halfbody 121 separately, and tested wire 4 is extend into the iron core 12 and iron core-closed 12 from opening part, and at this moment, tested wire 4 is equivalent to the coil of a single turn, measured current I wherein
3With magnetic test coil 13 process mutual inductance effects, in magnetic test coil 13, produce a mutual inductance electric current I
4(number of turn of establishing magnetic test coil 13 is n, then I
4=I
3/ n), the mutual inductance electric current I
4Through inputing to dsp chip 24 behind I/V converter 25, the A/D sampling thief 26, dsp chip 24 multiply by correction coefficient P with the sampled value that obtains, and after through conversion, can calculate corresponding measured current I
3And be presented on the LCD 28.
Obviously, from foregoing description as can be seen owing to measuring measured current I
3Use the correction branch road that clamp on amperemeter 3 has been carried out error correction before, and obtained correction coefficient P, therefore, measuring measured current I
3The time, measurement result be multiply by this correction coefficient P can be to I
3Error proofread and correct.
More than be the comparatively typical embodiment of forcipated mutual-inductor 1 of the present invention and clamp on amperemeter 3, forcipated mutual-inductor 1 in fact of the present invention and clamp on amperemeter 3 are not limited to above-mentioned structure.In fact, the auxiliary circuit 2 described in Fig. 2 is the structural representation of circuit just, and auxiliary circuit 2 can be incorporated within the module fully, and this module can be installed among the forcipated mutual-inductor 1, and then forms a complete clamp on amperemeter; If consider the volume (being of value to the operator grips) that dwindles forcipated mutual-inductor 1, so also auxiliary circuit can be designed to the equipment of circumscribed, the equipment of this circumscribed can be connected with forcipated mutual-inductor 1 by cable, perhaps be designed to pluggable form, in the use two joints 140,141 of two joints 130,131 of magnetic test coil 13 and correcting coil 14 are inserted respectively in the corresponding jack and get final product, in fact, this design of electronic devices scheme right and wrong are usually seen.
In addition, forcipated mutual-inductor 1 of the present invention can also have a lot of different embodiments with clamp on amperemeter 3, the clamp on amperemeter among Fig. 4 for example, it has added feedback line 240 between adjustable signal generator 20 and dsp chip 24, make signal magnitude that adjustable signal generator 20 produced, phase place etc. carry out suitable adjustment, make circuit more optimize according to the feedback of dsp chip.In addition, be apparent that very much, adopted the mode of voltage sample in the foregoing description, if change the current sample mode into is same feasible, in fact, after adopting the current sample mode, V/I converter and I/V converter can omit, and only need adjust signal generator and A/D sampling thief to get final product.Below embody this point to knowing in the description of clamp on amperemeter automatic correcting method.
Clamp on amperemeter automatic correcting method of the present invention can clearly show from Fig. 5.The A/D sampling thief 51 that has adopted adjustable current signal generator 50 among the described embodiment of Fig. 5 and can sample to electric current.Concrete bearing calibration is as follows: Closing Switch 52, make clamp on amperemeter enter correcting state, produce a current signal by adjustable current signal generator 50, this current signal flows through after the correcting coil with forcipated mutual-inductor, flow-out signal electric current 1 and marking current 2 from correcting coil and magnetic test coil respectively, suppose that correcting coil is identical with the number of turn of magnetic test coil, then respectively marking current 1 and marking current 2 are sampled by A/D sampling thief 51, and sampled result is input in the dsp chip, dsp chip compares marking current 1 and marking current 2, if the two is unequal (according to the number of turn relation of correcting coil and magnetic test coil, the two should equate), then marking current 2 be multiply by a correction coefficient P, its numerical value is equated with marking current 1, and show corresponding results by input-output device.
From said process as can be seen, on the structure of existing clamp on amperemeter, add a correcting coil,, can revise, improve the precision of measuring error through after the above-mentioned self-correcting process.
Obviously, above-mentioned forcipated mutual-inductor, clamp on amperemeter and clamp on amperemeter automatic correcting method can be made a lot of improvement and equivalent transformation, for example the handle of forcipated mutual-inductor can adopt other any be suitable for controlling iron core about the structure of two halfbody foldings, correcting coil and magnetic test coil also can be flexible and changeable: both can lay respectively on two halfbodies of iron core, also can be positioned on the same halfbody; Dsp chip also can use other chip with computing power or equipment to replace; In addition, the foregoing description has only been introduced the process of size of current being carried out calibration, in fact, after adopting suitable dsp chip, also can adopt similar method and structure that the error on the phase place is also proofreaied and correct.Suchlike minor alteration and equivalent transformation all should be included within the described scope of claim.
Claims (10)
1, forcipated mutual-inductor, comprise housing, be contained in the iron core in the housing, be arranged on first coil on the iron core, iron core is divided into two separable halfbodies, two halfbodies that also comprise a control iron core on the described housing separate or the mechanism of combination, it is characterized in that: also be provided with second coil on the iron core, described second coil is connected between the signal generator and second sampling thief, described second sampling thief is electrically connected with data processing unit, described second coil is excited in described first coil by described signal generator and generates induction current, and described data processing unit generates the correction coefficient that keeps the involution relation with the described induction current of described first coil after relatively flowing through the excitation current of described second coil and flowing through the described induction current of described first coil.
2, forcipated mutual-inductor according to claim 1 is characterized in that: two halfbodies of control iron core separate or the mechanism of combination is " X " shape handle.
3, forcipated mutual-inductor according to claim 1 is characterized in that: first coil and second coil lay respectively on two halfbodies, and the equal turn numbers of the number of turn of first coil and second coil.
4, clamp on amperemeter, comprise forcipated mutual-inductor and auxiliary circuit, described forcipated mutual-inductor comprises housing, be contained in the iron core in the housing, be arranged on first coil on the iron core, iron core is divided into two separable halfbodies, auxiliary circuit comprises first sampling thief of connecting with first coil, it is characterized in that: described forcipated mutual-inductor further comprise one can with second coil of the first coil generation mutual inductance effect, auxiliary circuit further comprises the signal generator that is connected second coil, one end, be connected second sampling thief and the data processing unit of the second coil other end, described first sampling thief all is connected with data processing unit with second sampling thief, described second coil is excited in described first coil by described signal generator and generates induction current, and described data processing unit generates the correction coefficient that keeps the involution relation with the described induction current of described first coil after relatively flowing through the excitation current of described second coil and flowing through the described induction current of described first coil.
5, clamp on amperemeter according to claim 4 is characterized in that: described auxiliary circuit also comprises the input-output device that is connected with data processing unit.
6, clamp on amperemeter according to claim 4 is characterized in that: the front end of described first sampling thief and second sampling thief all is provided with an I/V converter.
7, clamp on amperemeter according to claim 4 is characterized in that: comprise a feedback circuit between described signal generator and the data processing unit.
8, clamp on amperemeter according to claim 4 is characterized in that: between the described signal generator and second coil electric switch is set.
9, clamp on amperemeter automatic correcting method, described clamp on amperemeter comprises forcipated mutual-inductor and auxiliary circuit, described forcipated mutual-inductor comprises housing, be contained in iron core in the housing, be arranged on the iron core first coil and can with second coil of the first coil generation mutual inductance effect, iron core is divided into two separable halfbodies, auxiliary circuit comprises first sampling thief, second sampling thief of connecting with first coil, second coil, first sampling thief all is connected with data processing unit with second sampling thief, said method comprising the steps of:
One standard electric signal is input in second coil, and in first coil, produces a mutual inductance electric signal;
Use first sampling thief, second sampling thief that standard electric signal and mutual inductance electric signal are sampled respectively;
In data processing unit, above-mentioned two sampled result are compared, and determine a correction coefficient P.
10, clamp on amperemeter automatic correcting method according to claim 9 is characterized in that: the equal turn numbers of the number of turn of described first coil and second coil, putting before this, and mutual inductance signal equals the product of standard signal and correction coefficient P.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CNB2005100366752A CN100432680C (en) | 2005-08-24 | 2005-08-24 | Forcipated mutual-inductor, forcipated ammeter and verification method of forcipated ammeter |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CNB2005100366752A CN100432680C (en) | 2005-08-24 | 2005-08-24 | Forcipated mutual-inductor, forcipated ammeter and verification method of forcipated ammeter |
Publications (2)
Publication Number | Publication Date |
---|---|
CN1920580A CN1920580A (en) | 2007-02-28 |
CN100432680C true CN100432680C (en) | 2008-11-12 |
Family
ID=37778342
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CNB2005100366752A Active CN100432680C (en) | 2005-08-24 | 2005-08-24 | Forcipated mutual-inductor, forcipated ammeter and verification method of forcipated ammeter |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN100432680C (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8754636B2 (en) | 2011-12-07 | 2014-06-17 | Brymen Technology Corporation | Clamp meter with multipoint measurement |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102011080874B4 (en) * | 2011-08-12 | 2015-01-22 | Bender Gmbh & Co. Kg | electrical measuring device, electrical measuring device for measuring electrical currents and calibration methods |
CN102313879B (en) * | 2011-09-19 | 2014-09-17 | 贵州电力试验研究院 | Electronic current transformer on-line checking system based on double-clamp current coil |
CN103105525B (en) * | 2011-11-15 | 2014-12-17 | 华北电力科学研究院有限责任公司 | Precision compensation method of current clamp, detection method and detection system using current clamp |
CN103134978B (en) * | 2011-11-24 | 2016-01-13 | 錞镱科技股份有限公司 | Can the hook table of multimetering |
EP2653876B1 (en) * | 2012-04-20 | 2014-09-03 | ABB Technology AG | Arrangement for measuring a current with a current transducer of the Rogowski type |
CN103983843B (en) * | 2014-05-30 | 2016-06-01 | 杭州佳和电气股份有限公司 | Compensation algorithm when application forcipated mutual-inductor measures wattful power and electric energy |
CN105548813B (en) * | 2016-01-06 | 2018-08-14 | 天津浩源慧能科技有限公司 | A kind of tower grounding failure detector and detection method |
CN106645861B (en) * | 2017-02-17 | 2020-11-10 | 三峡大学 | Online current transformer checking system based on pincerlike Rogowski coil |
CN109975591B (en) * | 2019-03-28 | 2024-02-23 | 漳州市玉山电子制造有限公司 | AC pincerlike multipurpose meter and coil winding method thereof |
CN111025218B (en) * | 2019-12-30 | 2022-07-08 | 珠海市科荟电器有限公司 | System and method for online real-time self-calibration of clamp-on ammeter |
CN112964928B (en) * | 2021-02-24 | 2024-01-30 | 优利德科技(中国)股份有限公司 | Clamp ammeter without integrated magnet core and automatic balance adjustment method |
FR3125594B3 (en) * | 2021-07-23 | 2023-09-15 | Totalenergies Renewables | Electrical verification circuit for current clamp, current clamp and corresponding verification method |
CN113567906A (en) * | 2021-07-27 | 2021-10-29 | 胡翠翠 | Novel adjustable mutual inductor calibration equipment and calibration method thereof |
CN114284047B (en) * | 2022-03-04 | 2022-06-14 | 山西省机电设计研究院有限公司 | Open-close bus type high-precision zero-flux current transformer and error compensation method |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4616174A (en) * | 1983-09-15 | 1986-10-07 | Danfysik A/S | Detector circuit for current measurements |
CN86108441A (en) * | 1986-12-18 | 1988-06-29 | 中国船舶工业总公司第七研究院第七一五研究所 | Automatic mutual-inductor calibrating instrument |
CN2071792U (en) * | 1990-04-15 | 1991-02-20 | 张振乾 | Electric energy metering on-line detector for clamp mutual-inductor |
CN2109573U (en) * | 1991-12-28 | 1992-07-08 | 杭州东海仪表厂 | Wide measuring range small current pincerlike meter |
CN2125144U (en) * | 1992-05-06 | 1992-12-16 | 付杰民 | Resonant clamp type amperemeter |
CN2339994Y (en) * | 1998-05-09 | 1999-09-22 | 华中理工大学 | 220 KV active optic-fiber current transformer |
CN2412283Y (en) * | 2000-03-12 | 2000-12-27 | 赵义林 | Pincerlike mutual inductor |
CN1329339A (en) * | 2000-06-15 | 2002-01-02 | 沈阳电力工程技术研究所 | High-voltage light-channel split core type current transformer |
CN2518111Y (en) * | 2001-11-07 | 2002-10-23 | 孙继叔 | Universal forcipated current meter |
CN2669335Y (en) * | 2003-05-22 | 2005-01-05 | 西安双英科技有限公司 | Small-pliers shape current universal inductor |
CN2687682Y (en) * | 2004-02-11 | 2005-03-23 | 朱建新 | Clamp type electricity detecting meter |
-
2005
- 2005-08-24 CN CNB2005100366752A patent/CN100432680C/en active Active
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4616174A (en) * | 1983-09-15 | 1986-10-07 | Danfysik A/S | Detector circuit for current measurements |
CN86108441A (en) * | 1986-12-18 | 1988-06-29 | 中国船舶工业总公司第七研究院第七一五研究所 | Automatic mutual-inductor calibrating instrument |
CN2071792U (en) * | 1990-04-15 | 1991-02-20 | 张振乾 | Electric energy metering on-line detector for clamp mutual-inductor |
CN2109573U (en) * | 1991-12-28 | 1992-07-08 | 杭州东海仪表厂 | Wide measuring range small current pincerlike meter |
CN2125144U (en) * | 1992-05-06 | 1992-12-16 | 付杰民 | Resonant clamp type amperemeter |
CN2339994Y (en) * | 1998-05-09 | 1999-09-22 | 华中理工大学 | 220 KV active optic-fiber current transformer |
CN2412283Y (en) * | 2000-03-12 | 2000-12-27 | 赵义林 | Pincerlike mutual inductor |
CN1329339A (en) * | 2000-06-15 | 2002-01-02 | 沈阳电力工程技术研究所 | High-voltage light-channel split core type current transformer |
CN2518111Y (en) * | 2001-11-07 | 2002-10-23 | 孙继叔 | Universal forcipated current meter |
CN2669335Y (en) * | 2003-05-22 | 2005-01-05 | 西安双英科技有限公司 | Small-pliers shape current universal inductor |
CN2687682Y (en) * | 2004-02-11 | 2005-03-23 | 朱建新 | Clamp type electricity detecting meter |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8754636B2 (en) | 2011-12-07 | 2014-06-17 | Brymen Technology Corporation | Clamp meter with multipoint measurement |
Also Published As
Publication number | Publication date |
---|---|
CN1920580A (en) | 2007-02-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN100432680C (en) | Forcipated mutual-inductor, forcipated ammeter and verification method of forcipated ammeter | |
CN101865986B (en) | System and method for checking error of high-voltage electric energy measurement device | |
AU2014247351B2 (en) | Method and device for testing a transformer | |
KR102180016B1 (en) | Portable Current Transformer Excitation And Core Characteristics Tester | |
CN101256204B (en) | Current detecting device and calibration method | |
CN201425621Y (en) | Error checking system of high-voltage electric energy metering device | |
CN104569897B (en) | A kind of electronic current mutual inductor check system based on standard Rogowski coil | |
US20060250117A1 (en) | Power Factor Correction Analysis System and Method | |
CN103592490B (en) | A kind of high accuracy electronic compensation type current transformer | |
CN101118269A (en) | Wire connection analyse device for electric power protective circuit | |
CN208818818U (en) | A kind of low-power consumption program control type current mutual inductor field detecting device | |
CN104730485A (en) | GIS type current transformer test method | |
CN108761375A (en) | A kind of low-power consumption program control type current mutual inductor field detecting device | |
CN101639524B (en) | Field detecting device of current mutual inductor for protection | |
CN108363029B (en) | Calibration system and calibration method for direct current sensor | |
KR102191783B1 (en) | Portable Current Transformer Ratio Tester | |
CN203606413U (en) | High-accuracy electronic compensation type current transformer | |
Kadar et al. | The effect of current and voltage transformers accuracy on harmonic measurements in electric arc furnaces | |
CN104880686A (en) | Device and method for checking portable electronic current transformer | |
CN101545963A (en) | High-performance current transformer intelligent analyzer | |
CN204719222U (en) | A kind of portable electronic piece formula current transformer calibration device | |
CN204439764U (en) | Transformer parameter comprehensive tester | |
CN210038140U (en) | Full-range self-calibration device for mutual inductor | |
CN115561695B (en) | Three-phase current transformer on-site verification device and method | |
CN207937587U (en) | A kind of detection device and detecting system of electric mutual inductor |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant |