CN204086388U - A kind of variable-frequency electric component analysis instrument based on digital quantity transmission - Google Patents
A kind of variable-frequency electric component analysis instrument based on digital quantity transmission Download PDFInfo
- Publication number
- CN204086388U CN204086388U CN201420233039.3U CN201420233039U CN204086388U CN 204086388 U CN204086388 U CN 204086388U CN 201420233039 U CN201420233039 U CN 201420233039U CN 204086388 U CN204086388 U CN 204086388U
- Authority
- CN
- China
- Prior art keywords
- power cell
- variable
- component analysis
- electric component
- analysis instrument
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000004458 analytical method Methods 0.000 title claims abstract description 31
- 230000005540 biological transmission Effects 0.000 title claims abstract description 29
- 238000004891 communication Methods 0.000 claims abstract description 20
- 238000005259 measurement Methods 0.000 claims description 33
- 239000013307 optical fiber Substances 0.000 claims description 10
- 238000012545 processing Methods 0.000 abstract description 6
- 238000010276 construction Methods 0.000 abstract description 4
- 230000008054 signal transmission Effects 0.000 abstract description 3
- 238000006243 chemical reaction Methods 0.000 description 10
- 238000005070 sampling Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 7
- 230000001360 synchronised effect Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000005611 electricity Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000006870 function Effects 0.000 description 3
- 238000003869 coulometry Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 230000036039 immunity Effects 0.000 description 2
- 230000005693 optoelectronics Effects 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000004082 amperometric method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000013632 homeostatic process Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000004445 quantitative analysis Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Landscapes
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
Abstract
The utility model provides a kind of variable-frequency electric component analysis instrument based on digital quantity transmission, comprises power cell, analyser and communication unit; Power cell comprises at least one power cell single-piece, and power cell single-piece comprises sample unit, signal transmitting device, signal condition parts and the A/D converter of connecting successively; Analyser comprises CPU module, Programmadle logic device, cache memory and display screen, and CPU module is connected with display screen, Programmadle logic device and cache memory respectively; Programmadle logic device is connected with A/D converter by communication unit.The utility model one-piece construction is simplified; Analog quantity is converted to digital signal transmission by power cell, avoids the impact of transmission range and electromagnetic environment, improves the precision of system; By integrated CPU module, Programmadle logic device and cache memory, improve its arithmetic speed and processing power.
Description
Technical field
The utility model relates to instrument field, especially, relates to a kind of variable-frequency electric component analysis instrument based on digital quantity transmission.
Background technology
Traditional coulometric analysis instrument is in the following ways: front end sensors changes voltage, ER effect into secondary instrument acceptable small-signal (simulating signal), and simulating signal carries out no-load voltage ratio conversion and display by cable transmission to secondary instrument.The measuring accuracy of so whole measuring system how homeostasis? according to the composition situation of measuring system, the measuring accuracy of system should be determined by following three aspects: 1, the precision of front end sensors; 2, transmission line introduce interference and signal attenuation; 3, the measuring accuracy of secondary instrument.This kind of technical sensor adopts cable to be connected with secondary, if front end sensors generation insulation breakdown or short circuit phenomenon, so high pressure can directly pass through cable conducting to secondary instrument side, namely user side, so for user, it is a very large potential safety hazard.
Along with the development of converter technique, the electromagnetic environment of measure field is day by day severe, and the electromagnetic interference (EMI) brought by frequency conversion equipment is also more and more serious.The signal transmission form adopted due to measuring system is analog quantity transmission, therefore its electromagnetic interference (EMI) be subject to can have a strong impact on the measuring accuracy of system, in the occasion that electromagnetic interference (EMI) is strong, some equipment even cisco unity malfunction, let alone measure accurate, such measuring system, nominal accuracy loses meaning.
Analyze from principle, existing frequency conversion instrument can in the following ways: refer to accompanying drawing 1, the parts 1-2 of this structure is as a whole, and parts 1-2 is usually used as an independent instrument, and digital transmission system is often realized by PCB, and path is very short; Parts 1-1 is component analysis instrument system together with parts 1-2, and the analog quantity transmission link between parts 1-1 and parts 1-2 adopts cable, and cable length needs according to test site and determines, and is the link easily introducing loss and interference; This structure member 1-1, parts 1-2 and analog quantity transmission link all may introduce error (mainly the factor such as electromagnetic interference (EMI) and signal attenuation), and degree of accuracy is not high; System accuracy is determined by voltage sensor, current sensor, hop, secondary transducer portion, and introduce error link many, most equipment applicable elements is power frequency environment, is not suitable for the measurement of frequency conversion electricity.
Utility model content
The utility model object is to provide a kind of variable-frequency electric component analysis instrument based on digital quantity transmission that the parts likely affecting precision are all concentrated on power cell, and be converted to digital signal output, then analyser is reached by communication unit, the signal attenuation carried out communication owing to adopting digital form and can avoid completely causing in on-the-spot electromagnetic interference (EMI) and signals transmission, therefore, ensure that the precision of whole device and entirety are traced to the source ability, concrete technical scheme is as follows:
Based on a variable-frequency electric component analysis instrument for digital quantity transmission, comprise power cell, analyser and communication unit;
Described power cell comprises at least one power cell single-piece, and described power cell single-piece comprises sample unit, signal transmitting device, signal condition parts and the A/D converter of connecting successively;
Described analyser comprises CPU module, Programmadle logic device, cache memory and display screen, and described CPU module is connected with described display screen, Programmadle logic device and cache memory respectively; Described Programmadle logic device is connected with described A/D converter by communication unit.
Preferred in above technical scheme, described power cell comprises two power cell single-pieces be set up in parallel, and a described power cell single-piece comprises voltage collector, voltage signal transmitter, signal condition parts and the A/D converter of connecting successively; Power cell single-piece described in another comprises current collector, current signal transmitter, signal condition parts and the A/D converter of connecting successively.
Preferred in above technical scheme, described signal condition parts comprise LPF low-pass filter and auto-shifted measurement device, and described LPF low-pass filter and auto-shifted measurement device are connected between described voltage signal transmitter and described A/D converter and between current signal transmitter and described A/D converter successively respectively.
Preferred in above technical scheme, described communication unit is cable or optical fiber.
Preferred in above technical scheme, described Programmadle logic device is provided with 6 interfaces.
Preferred in above technical scheme, described Programmadle logic device is also provided with subtending port.
Preferred in above technical scheme, described power cell also comprises phase compensator, frequency measurement parts and synchronisation source switching part, described frequency measurement parts and synchronisation source switching part are arranged in series between described auto-shifted measurement device and described communication unit, and in parallel with described A/D converter, described synchronisation source switching part is connected with described Programmadle logic device; Described phase compensator is arranged between described auto-shifted measurement device and described frequency measurement parts.
Preferred in above technical scheme, described power cell is built-in pcb board.
Preferred in above technical scheme, described Programmadle logic device is the EPM1270 of nS rank; The model of described CPU module is T2500.
The utility model has following beneficial effect:
(1) the variable-frequency electric component analysis instrument based on digital quantity transmission of the present utility model comprises power cell, analyser and communication unit three parts, and one-piece construction is simplified; Power cell comprises sample unit, signal transmitting device, signal condition parts and the A/D converter of connecting successively, gather by adopting parts, again through analog quantity is converted to digital signal transmission, avoid transmission range and electromagnetic environment on the impact that signal produces in transmitting procedure, the precision of raising system; Analyser is integrated by CPU module, Programmadle logic device and cache memory, substantially increase its arithmetic speed and processing power, thus improve its analysis times, and also have function digital signal being stored and shows concurrently simultaneously, practical.
(2) in the utility model, power cell comprises two power cell single-pieces be set up in parallel, and can realize carrying out accurate analysis to the voltage gathered, electric current.
(3) in the utility model, signal condition parts comprise LPF low-pass filter and auto-shifted measurement device, filtering is carried out to the signal gathered and uses 2N automatic seamless range swithching technology automatically to select optimum measurement range, improve the degree of accuracy of single unit system.
(4) in the utility model, communication unit adopts cable or optical fiber, and parts easily obtain, strong interference immunity, and optical fiber has electric isolution effect, and the personal safety for user is secure, improve the security performance in its use procedure; In addition, can also the modes such as wireless connections be adopted according to the actual requirements to transmit.
(5) in the utility model, Programmadle logic device is provided with for 6 interfaces, can meet six feature quantitative analyses simultaneously; Also be provided with subtending port, can realize analyzing unnecessary 6 characteristic quantities simultaneously, specifically analyser be carried out cascade, synchronous acquisition, meet the different needs, practical.
(6) in the utility model, power cell also comprises phase compensator, frequency measurement parts and synchronisation source switching part, some signal is carried out to the switching etc. of phase compensation, frequency measurement, synchronism, the synchronism of each signal is regulated and controled, greatly improves the accuracy of its analysis result.
(7) power cell described in the utility model is built-in pcb board, adopts embedding structure, both can extend its serviceable life, and can reduce again the overall volume of device, and greatly save space and reduce the interference of external environment.
(8) in the utility model, Programmadle logic device adopts the EPM1270 of nS rank, ensure that the synchronism of sampling rate up to 250kHz and multiple power cell sampling time sequence; The model of CPU module is T2500, in conjunction with DFT discrete fourier algorithm, conversion is counted or sampling rate is selected more flexible, real-time is better, easier Control strain and dynamic range, computing programming is simple, can programme easily, greatly can improve its analysis times (can reach more than 2000 times) in non-dsp chip.
Except object described above, feature and advantage, the utility model also has other object, feature and advantage.Below with reference to figure, the utility model is described in further detail.
Accompanying drawing explanation
The accompanying drawing forming a application's part is used to provide further understanding of the present utility model, and schematic description and description of the present utility model, for explaining the utility model, is not formed improper restriction of the present utility model.In the accompanying drawings:
Fig. 1 is the structural drawing in technical background;
Fig. 2 is the one-piece construction schematic diagram of the variable-frequency electric component analysis instrument based on digital quantity transmission of the utility model preferred embodiment 1;
Fig. 3 is variable-frequency electric component analysis instrument and the existing WT3000 power analyzer measuring accuracy curve comparison diagram under sine wave and PWM waveform condition based on digital quantity transmission in Fig. 2;
1-power cell, 01-voltage collector, 01 '-current collector, 02-voltage signal transmitter, 02 '-current signal transmitter, 03-signal condition parts, 031-LPF low-pass filter, 032-auto-shifted measurement device, 04-A/D converter, 05-phase compensator, 06-frequency measurement parts, 07-synchronisation source switching part, 2-analyser, 21-CPU module, 22-Programmadle logic device, 221-interface, 222-subtending port, 23-cache memory, 24-display screen, 3-communication unit.
Embodiment
Below in conjunction with accompanying drawing, embodiment of the present utility model is described in detail, but the multitude of different ways that the utility model can limit according to claim and cover is implemented.
Embodiment 1:
A kind of variable-frequency electric component analysis instrument based on digital quantity transmission, refer to Fig. 2, specifically comprise power cell 1, analyser 2 and communication unit 3, described power cell 1 is built-in pcb board, adopt embedding structure, both can extend its serviceable life, the overall volume of device can be reduced again, greatly save space and reduce the interference of external environment, one-piece construction is simplified.
Described power cell 1 comprises two power cell single-pieces arranged side by side, described power cell single-piece comprise connect successively voltage collector 01, voltage signal transmitter 02, signal condition parts 03, A/D converter 04 and connect successively and the frequency measurement parts 06 in parallel with A/D converter 04 and synchronisation source switching part 07, described in another, power cell single-piece comprises the current collector 01 ' of connecting successively, current signal transmitter 02 ', signal condition parts 03, phase compensator 05, A/D converter 04 and connect successively and the frequency measurement parts 06 in parallel with A/D converter 04 and synchronisation source switching part 07, respectively signal condition is carried out to the voltage collected by two power cell single-pieces, range swithching, frequency measurement, opto-electronic conversion etc. process and carry out signal condition to the electric current collected, range swithching, phase compensation, frequency measurement, the process such as opto-electronic conversion, voltage and current signal is converted to digital signal.
Described signal condition parts 03 comprise the LPF low-pass filter 031 and auto-shifted measurement device 032 of connecting successively, described LPF low-pass filter 031 is for carrying out filtering to the variable adopted, described auto-shifted measurement device 032 adopts 2N automatic seamless range swithching technology, each power cell arranges 8 gears, according to measurement instantaneous value, automatic selection optimum measurement range, each range is only operated in 50% ~ 100% range ability, improves the accuracy detected.
Described analyser 2 comprises display screen 24, CPU module 21, Programmadle logic device 22 and cache memory 23, described CPU module 21 is connected with described display screen 24, Programmadle logic device 22, cache memory 23 and A/D converter 04 respectively, and its inside is provided with DFT discrete fourier algorithm, described Programmadle logic device 22 is connected with described A/D converter 04 by communication unit 3, wherein CPU module 21 adopts the EMETM-i945m/T2500 of ARBOR, integrated Intel Core 2 Duo/Core Duo 65nm Processor low power processor, dominant frequency is 2.0GHz, front-side bus frequency FSB is 667MHz, 1x200Pin SO-DIMM slot, maximum support 2GB DDR2SDRAM, for high performance double-core embedded type CPU module, and it adopts DFT discrete fourier algorithm to convert, the conversion of Appropriate application DFT discrete fourier algorithm is counted or sampling rate is selected more flexible, real-time is better, easier Control strain and dynamic range, computing programming is simple, can the advantage such as programming realization in non-dsp chip easily, be applicable to meet because measuring the unknown of front first-harmonic the situation that sample number is 2N and complete cycle during frequency conversion output is measured simultaneously, greatly improve its arithmetic speed and processing power, Programmadle logic device 22 adopts the FPGA of the high timing of nS rank, specifically selects the EPM1270 of ALTERA company, ensure that the synchronism of sampling rate up to 250kHz and multiple power cell single-piece sampling time sequence, cache memory 23 adopts FIFO Cache, and double-core embedded type CPU module and the running memory up to 2G Byte ensure that arithmetic speed and the operation time of DFT algorithm, improves its arithmetic speed and processing power further.
Described communication unit 3 is optical fiber, the voltage of Real-time Collection, current signal are sent to described analyser 2 by optical fiber TXD port and carry out the process such as computing, display by power cell 1, power cell 1 is also by the synchronous sequence signal that the RXD port accepts analyser 2 of optical fiber sends in addition, ensures the synchronism of signal sampling between multiple power cell single-piece; Optical fiber also has electric isolution effect, and the personal safety for user is secure, improves the security performance that it uses.
Described Programmadle logic device 22 is provided with 6 interfaces 221 for being connected with power cell single-piece, carries out communication between the two by optical fiber, ensures the precision in data transfer; Described Programmadle logic device 22 is also provided with subtending port 222, when system needs connect the power cell single-piece more than 6 and when requiring synchronous acquisition, by subtending port 222, power cell single-piece can be carried out cascade, realize synchronous acquisition, meet the different needs, practical.
Described synchronisation source switching part 07 is connected with described Programmadle logic device 22, is convenient to the synchronous sequence signal that receiving and analyzing instrument 2 sends, and ensures the synchronism of signal sampling between multiple power cell single-piece.
Apply the variable-frequency electric component analysis instrument based on digital quantity transmission of the present utility model, described CPU module 21 can carry out computing and process according to various GB to data, then show on the display 24, analyser 2 completes the data processing of voltage and current, and by result display on the display 24, display mode on the display 24 has numerical value, real-time waveform, chart and histogram etc. multiple; In addition, analyser 2 can also configure integrated 18 kinds of wiring diagrams can selected for user and the algorithm mated with wiring diagram, different according to the power cell mode of connection, can select different wiring diagrams and display mode; Analyser 2 sends synchronous acquisition signal by optical fiber transmit port to power cell 1, the synchronous logic sequential of managing power unit single-piece; Analyser 2 can also be equipped with RJ45 interface, share data by TCP/IP and other host computers, data save mode has bmp sectional drawing and transient data two kinds of modes, preserves data length and depends on external mobile storage medium capacity, preserving target is external mobile memory device, such as USB2.0.Measuring voltage scope contains 100uV ~ 15kV, measures range of current and contains 100uA ~ 7000A.
The variable-frequency electric component analysis instrument adopting the utility model transmit based on digital quantity and the measuring accuracy curve comparison diagram of existing WT3000 power analyzer under sine wave and PWM waveform condition are as shown in Figure 3, wherein, curve 1 is the measuring accuracy curve of WT3000 power analyzer under sinusoidal wave condition, as seen from the figure, optimum precision measurement point under its sinusoidal wave condition is near 50Hz, and the measuring accuracy of other frequency ranges departs from nominal accuracy far away; Curve 2 is the measuring accuracy curve of WT3000 power analyzer under PWM waveform condition, and it is lower in the measuring accuracy of low-frequency range, and the first-harmonic not being suitable for lower frequency section is measured; The measuring accuracy curve of the utility model device under sinusoidal wave condition and the measuring accuracy curve under PWM waveform condition overlap completely, as curve 3 illustrates, as seen from the figure, adopt variable-frequency electric quantitative analysis device of the present utility model, accuracy of measurement is no matter under which kind of measuring condition, remain consistent, accuracy is improved greatly.
In addition, each analyser 2 can also be analyzed according to the power quality of various GB to tested electricity, provide each parameter value, as telephone harmonic form factor (THF), total harmonic distortion (THD), harmonic voltage factor (HVF), harmonic content (HC), irregularity of wave form (K%) etc.; In addition, each analyser 2 can also connect the power cell single-piece more than 6 side by side, and the data processing mainly completed has: each measurement pattern (H01, rms, mean, avg) power under, harmonic wave, frequency, power factor, harmonic content, power quality etc., by Function Extension interface, the functions such as expansion moment of torsion, rotating speed, temperature survey also show, the same voltage of analysis principle, amperometry principle.
Be specifically designed to the coulometric analysis instrument of frequency conversion electricity accurate analysis instrument and test, also can be used for the Measurement accuracy of frequency electric simultaneously.
Described communication unit 3 can also adopt cable or radio connection, strong interference immunity, is also suitable for remote and that interference is strong environment, practical.
The foregoing is only preferred embodiment of the present utility model, be not limited to the utility model, for a person skilled in the art, the utility model can have various modifications and variations.All within spirit of the present utility model and principle, any amendment done, equivalent replacement, improvement etc., all should be included within protection domain of the present utility model.
Claims (9)
1., based on a variable-frequency electric component analysis instrument for digital quantity transmission, it is characterized in that: comprise power cell (1), analyser (2) and communication unit (3);
Described power cell (1) comprises at least one power cell single-piece, and described power cell single-piece comprises sample unit, signal transmitting device, signal condition parts (03) and the A/D converter (04) of connecting successively;
Described analyser (2) comprises CPU module (21), Programmadle logic device (22), cache memory (23) and display screen (24), and described CPU module (21) is connected with described display screen (24), Programmadle logic device (22) and cache memory (23) respectively; Described Programmadle logic device (22) is connected with described A/D converter (04) by communication unit (3).
2. the variable-frequency electric component analysis instrument based on digital quantity transmission according to claim 1, it is characterized in that: described power cell (1) comprises two power cell single-pieces be set up in parallel, a described power cell single-piece comprises voltage collector (01), voltage signal transmitter (02), signal condition parts (03) and the A/D converter (04) of connecting successively; Power cell single-piece described in another comprises current collector (01 '), current signal transmitter (02 '), signal condition parts (03) and the A/D converter (04) of connecting successively.
3. the variable-frequency electric component analysis instrument based on digital quantity transmission according to claim 2, it is characterized in that: described signal condition parts (03) comprise LPF low-pass filter (031) and auto-shifted measurement device (032), described LPF low-pass filter (031) and auto-shifted measurement device (032) are connected between described voltage signal transmitter (02) and described A/D converter (04) and between current signal transmitter (02 ') and described A/D converter (04) successively respectively.
4. the variable-frequency electric component analysis instrument based on digital quantity transmission according to claim 3, is characterized in that: described communication unit (3) is cable or optical fiber.
5. the variable-frequency electric component analysis instrument based on digital quantity transmission according to claim 4, is characterized in that: described Programmadle logic device (22) is provided with 6 interfaces (221).
6. the variable-frequency electric component analysis instrument based on digital quantity transmission according to claim 5, is characterized in that: described Programmadle logic device (22) is also provided with subtending port (222).
7. the variable-frequency electric component analysis instrument based on digital quantity transmission according to claim 3, it is characterized in that: described power cell (1) also comprises phase compensator (05), frequency measurement parts (06) and synchronisation source switching part (07), described frequency measurement parts (06) and synchronisation source switching part (07) are arranged in series between described auto-shifted measurement device (032) and described communication unit (3), and it is in parallel with described A/D converter (04), described synchronisation source switching part (07) is connected with described Programmadle logic device (22), described phase compensator (05) is arranged between described auto-shifted measurement device (032) and described frequency measurement parts (06).
8. the variable-frequency electric component analysis instrument based on digital quantity transmission according to claim 7, is characterized in that: described power cell (1) is built-in pcb board.
9. the variable-frequency electric component analysis instrument based on digital quantity transmission according to claim 1-8 any one, is characterized in that: the EPM1270 that described Programmadle logic device (22) is nS rank; The model of described CPU module (21) is T2500.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201420233039.3U CN204086388U (en) | 2014-05-08 | 2014-05-08 | A kind of variable-frequency electric component analysis instrument based on digital quantity transmission |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201420233039.3U CN204086388U (en) | 2014-05-08 | 2014-05-08 | A kind of variable-frequency electric component analysis instrument based on digital quantity transmission |
Publications (1)
Publication Number | Publication Date |
---|---|
CN204086388U true CN204086388U (en) | 2015-01-07 |
Family
ID=52179089
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201420233039.3U Expired - Lifetime CN204086388U (en) | 2014-05-08 | 2014-05-08 | A kind of variable-frequency electric component analysis instrument based on digital quantity transmission |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN204086388U (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108089046A (en) * | 2017-10-30 | 2018-05-29 | 国网山东省电力公司临朐县供电公司 | Bidirectional measuring data acquisition device under looped network pattern |
-
2014
- 2014-05-08 CN CN201420233039.3U patent/CN204086388U/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108089046A (en) * | 2017-10-30 | 2018-05-29 | 国网山东省电力公司临朐县供电公司 | Bidirectional measuring data acquisition device under looped network pattern |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN104569902B (en) | Digital type electric energy meter power consumption measuring device and method | |
CN103135013B (en) | Data acquisition unit test and assessment system | |
CN203133168U (en) | Power harmonic detector | |
CN104111372A (en) | Analytical equipment of frequency conversion electricity based on digital transmission | |
CN211785733U (en) | Three-phase multifunctional metering system | |
CN104407209A (en) | Energy efficiency metering detection method of distribution transformer | |
CN202836819U (en) | Multi-channel temperature acquisition circuit of intelligent electric power monitor | |
CN101458275A (en) | High temperature resistant three phase intermediate frequency electric quantity acquisition module | |
CN204462246U (en) | A kind of HVDC (High Voltage Direct Current) transmission line corona loss measuring system | |
CN102323478A (en) | Flexible wide area power grid harmonic synchronous monitoring system | |
CN204116451U (en) | A kind of Energy Efficiency of Distribution Transformer measuring and testing device | |
CN204945273U (en) | A kind of power quality data harvester of self-adaptation mains frequency | |
CN204086388U (en) | A kind of variable-frequency electric component analysis instrument based on digital quantity transmission | |
CN202494744U (en) | Device for detecting quality of electric energy | |
CN202382873U (en) | Intelligent temperature transmitter | |
CN207263829U (en) | A kind of electric harmonic detector | |
CN103675593A (en) | Electrification testing system and method for zinc oxide arrester in armored cabinet | |
CN111505701A (en) | Compact accelerator beam phase and position measuring system and method | |
CN203275517U (en) | Multifunctional three-phase harmonic wave electric energy meter | |
CN206161783U (en) | Dry -type air -core reactor oscillating wave partial discharge test device based on interchange is stepped up | |
CN204131532U (en) | A kind of micro power radio communication test macro | |
CN107328989B (en) | Transformer substation overvoltage monitoring system and method based on wireless acquisition technology | |
CN203661059U (en) | Parallel carrier wave communication tester | |
CN202758019U (en) | Zinc oxide lightning arrester characteristic tester | |
CN102621409A (en) | Ship power grid power quality monitoring system research based on DSP (digital signal processor) |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
CX01 | Expiry of patent term |
Granted publication date: 20150107 |
|
CX01 | Expiry of patent term |