GB2321713A - High-voltage transmission line data transfer system - Google Patents
High-voltage transmission line data transfer system Download PDFInfo
- Publication number
- GB2321713A GB2321713A GB9702120A GB9702120A GB2321713A GB 2321713 A GB2321713 A GB 2321713A GB 9702120 A GB9702120 A GB 9702120A GB 9702120 A GB9702120 A GB 9702120A GB 2321713 A GB2321713 A GB 2321713A
- Authority
- GB
- United Kingdom
- Prior art keywords
- high voltage
- information
- voltage transmission
- transmission line
- processing
- 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.)
- Withdrawn
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/80—Optical aspects relating to the use of optical transmission for specific applications, not provided for in groups H04B10/03 - H04B10/70, e.g. optical power feeding or optical transmission through water
- H04B10/801—Optical aspects relating to the use of optical transmission for specific applications, not provided for in groups H04B10/03 - H04B10/70, e.g. optical power feeding or optical transmission through water using optical interconnects, e.g. light coupled isolators, circuit board interconnections
- H04B10/802—Optical aspects relating to the use of optical transmission for specific applications, not provided for in groups H04B10/03 - H04B10/70, e.g. optical power feeding or optical transmission through water using optical interconnects, e.g. light coupled isolators, circuit board interconnections for isolation, e.g. using optocouplers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
- G01R19/2513—Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
An electronic circuit (14) for processing high voltage transmission line (10) information. The electronic circuit (14) includes a signal conversion circuit (20) operating at a line potential (28) and operably coupled to at least one high voltage transmission line (10), for converting information on at least one line parameter of a high voltage transmission line into a processable format. The electronic circuit (14), further includes an opto-coupler (21) operably coupled to the signal conversion circuit (20) for transferring information on the at least one line parameter from the signal conversion circuit (20) to a processing circuit (22) at a ground potential (31) for processing the line parameter information from the signal conversion circuit. Isolating the high voltage lines from the processing circuits with the use of non magnetic components preserves characteristics of the measured high voltage lines such as bandwidth and harmonics.
Description
ELECTRONIC CIRCUIT
Field of the Invention
This invention relates to an electronic circuit. The invention is applicable to, but not limited to electronic circuits for measuring AC high voltage transmission lines.
Background of the Invention
An alarm and control system that controls high power electrical networks, and for example, generates alarm signals on any power failure, needs to be able to measure parameters of AC high voltage transmission lines in order to decide whether or not there is a power failure. Such parameters include voltage, current, phase and harmonics. One common method used to measure these parameters of the AC high voltage transmission lines is to transform the AC high voltage power into a more suitable form by use of transformers. The transformers isolate and attenuate the line voltages to a level that can be measured by an electronic measuring circuit.
A disadvantage of using transformers having magnetic elements is that the transformers introduce a phase error, linearity errors and attenuation in the transformed signal bandwidth. A common method used to eliminate the above errors is to calibrate the electronic circuit by inserting correction factors to the circuit. Using such a correction factor technique increases the circuit complexity, thereby increasing the circuit cost.
This invention seeks to provide an electronic circuit for measuring
AC high voltage transmission lines which mitigate at least some of the above mentioned disadvantages.
Summarv of the Invention
According to a first aspect of the present invention there is provided an electronic circuit for processing high voltage transmission line information. The electronic circuit comprises a signal conversion circuit operating at a first potential and operably coupled to at least one high voltage transmission line, for converting information on at least one line parameter of a high voltage transmission line into a processable format.
The electronic circuit further comprises an isolating device operably coupled to the signal conversion circuit for transferring information on the at least one line parameter from the signal conversion circuit to a processing circuit and a processing circuit at a second potential for processing the at least one line parameter information from the signal conversion circuit at a second potential dissimilar to the first potential.
The present invention is an electronic circuit for measuring AC high voltage transmission lines parameters by transforming the high voltage signals to digital signals for processing. The processing circuit is isolated from the signal converting circuit and therefore the AC high voltage transmission lines are not influenced by signals in the processing circuit.
Advantageously, with the present invention, an inexpensive, accurate electronic circuit with wide bandwidth, for measuring high voltage transmission lines parameters is provided.
In the preferred embodiment of the invention, the isolating device is an opto-coupler. Preferably, the first potential is a line potential of the at least one high voltage transmission line and the second potential is a ground potential.
In the preferred embodiment of the invention, the signal conversion circuit comprises an adapter, for example an attenuator, having a first side operably coupled to the at one high voltage transmission line and a second side connected to an input of a first converter, of which an output is connected to the opto-coupler. Furthermore, the processing circuit is connected to the output of the opto-coupler.
In the preferred embodiment of the invention, the processing circuit is powered by a power supply having a ground potential and the signal conversion circuit is powered by a DC to DC converter having a floating potential, coupled to the power supply via a transformer.
In the preferred embodiment of the invention, the adapter is an attenuator for the measurement of voltage and/or phase, and a shunt for the measurement of current.
In a second aspect of the present invention, a method for processing high voltage transmission line information, for example using the electronic circuit of the first aspect, is provided. The method comprises the steps of converting the information on at least one line parameter of a high voltage transmis'sion line into a processable format using a signal conversion circuit, transferring the process able format information to the processing circuit using an isolating device, for example an opto-coupler, and processing the infnrmation using a micro-processor to provide information on the at least one line parameter.
Preferably, the at least one line parameter is either voltage, current and/or phase.
In a third aspect of the present invention, an alarm and control system for processing high voltage transmission line information, of the first or second aspect of the invention, is provided. The alarm and control system comprises at least one remote terminal unit for monitoring the at least one high voltage transmission line. The at least one remote terminal unit comprises an electronic circuit for processing high voltage transmission line information which is operably coupled to at least one high voltage transmission line. The at least one remote terminal unit further comprises a communication device operably coupled to the electronic circuit for transmitting the high voltage transmission line parameters. The alarm and control system further comprises a master control unit operably coupled to the remote terminal unit for controlling the high voltage transmission line.
A preferred embodiment of the invention will now be described, by way of example only, with reference to the drawings.
Brief Description of the Drawings
FIG. 1 is a general view of a SCADA system for measuring high voltage transmission lines according to a preferred embodiment of the invention;
FIG. 2 is a block diagram of an electronic circuit for measuring AC high voltage transmission lines according to the preferred embodiment of the invention; d 6 FIG. 3 is a flow chart of a method of measuring an AC high voltage transmission lines using the preferred embodiment of the invention.
Detailed Description of the Drawmgs Referring first to FIG. 1, a SCADA system for controlling and monitoring AC high voltage transmission lines, according to a preferred embodiment of the invention, is shown. The SCADA system includes a
Remote Terminal Unit (RTU) 12, a central controller 17 and a main computer 18. The RTU 12 is connected to the AC high voltage transmission lines 10. The RTU 12 includes an electronic circuit 14 for measuring parameters of the AC high voltage transmission lines 10 and a communication device 16 for communicating via wire-line (as is shown) or via radio communication (not shown) to the central controller 17. The RTU 12 monitors the AC high voltage transmission lines 10 and sends the results to the central controller 17. The central controller 17, which is controlled by the main computer 18, processes the results and activates, for example, an alarm (not shown) or controls the line voltage (not shown).
The main computer 18 runs a computer program that programs the central unit 17 operation parameters.
After a brief description of the SCADA system a detailed description of the electronic circuit 14, with references to FIG. 2 will now be provided.
The electronic circuit 14 includes a signal conversion circuit 20, at a line potential 28, operably coupled to AC high voltage transmission lines 10 and a processing circuit 22 at a ground potential 31, via an isolating device, for example an opto-coupler 21, for processing information measured and converted by the signal conversion circuit 20. The opto coupler is a nonmagnetic isolator device and therefore no harmonic distortion is provided to the signal. The signal conversion circuit 20 includes an adapter 23, connected to an analogue-to-digital (A/D) converter 24, which in turn is connected to an input port 25 of the opto-coupler 21. The processing circuit 22 includes an output port 26 of the opto-coupler 21. The signal conversion circuit 20 is powered by a first power supply 29 which is connected to the line potential 28, the processing circuit being connected to a second power supply 30 which is connected to the ground potential 31.
The electronic circuit described above is preferably used for measuring parameters of an AC high power transmission line for use with a Supervisory Control And Data Acquisition (SCADA) system to control electrical networks and especially is used as AC analyser. Furthermore, there are no magnetic devices on the circuit and as such an inexpensive electronic circuit is provided to measure the AC high voltage transmission lines without producing harmonic distortion.
In operation, a voltage measurement of AC high voltage transmission lines 10 is performed as described hereafter. The adapter 23 is connected to AC high voltage transmission lines 10. The adapter 23 is, for example, a resistor network for attenuating the AC high voltage into a low level voltage, suitable for measurement by low power electronic components, for example, attenuating the AC high voltage to approximately 10 volts. When a current measurement is needed, the adapter 23 is, for example, a shunt resistor operably coupled to electronic circuit for measuring the current passing through the shunt resistor. The adapter 23 is connected to the analogue side of the A\D converter 24. The
A\D converter 24 transforms the low voltage into a digital signal. The digital output of the A\D converter 24 is connected to the input port 25 of the opto-coupler 21. The digital signal from the A\D converter is converted into a light energy by the input port 25 of the opto-coupler 21. The input port 25 of the opto-coupler 21 transmits the light energy to the output port 26 of the opto-coupler 21. The output port 26 of the opto-coupler 21 converts the light energy to a digital signal. The output port 26 of the opto-coupler device 21 is connected to a processing device 27. The output port 26 transfers the digital signal to the processing device 27. The processing device 27 is for example, a micro processor or a digital signal processor (DSP), and translates the digital signal into a voltage measurement of the AC high voltage transmission lines 10. The output of the electronic circuit 14 is transferred to the communication device 16 of the RTU 12. The RTU passes the measured information to the central unit 17. The central unit 17 process the information for controlling the electrical network or operates an alarm in case of a voltage failure.
The signal conversion circuit 20 of the electronic circuit 14, is powered by the frstpower supply 29 at a line potential 28. The processing circuit 22 is powered by the second power supply 30 at a ground potential 31.
Advantageously, by using two power supplies at different ground potentials, and using an opto-coupler device, an isolation between the signal conversion circuit 20 and the processing circuit 22 is achieved.
It is within the contemplation of the invention, that alternative arrangements for achieving this non-magnetic form of isolation may be implemented. Furthermore, an alternative way of powering the electronic circuit 14 would include the second power supply 30 powering the processing circuit 22 and with a DC to DC converter being additionally connected to the power supply 30 in order to power the signal conversion circuit 20. The DC to DC converter is powered from the second power supply 30 and has a transformer to isolate the ground potential from the line potential.
The preferred embodiment can be used as a measuring device for line parameters such as voltage, current, phase and/or harmonics, and therefor as a power fail sensor in a SCADA system.
Referring now to FIG. 3, a method for measuring parameters of the
AC high voltage transmission lines 10 is described.
The first step, step 100 is monitoring the AC high voltage transmission lines 10. The next step 102, is converting the high voltage transmission lines 10 into digital signals. The components that are involved in this step are the adapter 23 that attenuates the high voltage into a low voltage and the A\D converter 24 that converting the low voltage into digital signal. For example, the adapter 23 is a high power linear attenuator of 1 to 100 that attenuates 1000 volts into 10 volts. The digital signal is then transferred to the processing device 27 via the opto-coupler 21, as shown in step 104. The input port 25 of the opto-coupler 21 converts the digital signal into a light signal and the output port 26 converting the light signal into a digital signal again. The opto-coupler 21 isolates the measured signal from the processing device 27. In step 106, the processing device 27, interprets the digital signal into a voltage measurement, for example, the a 5 volt digital signal being representative of 500 volts. The digital word is passed by the RTU 12 to the central unit 17. The central unit 17 analyses the digital word and compares the measured voltage to predetermined Limit6, as shown in step 108. If the voltage is within these limits another cycle of monitoring the AC high voltage, step 100, will begin.
If the voltage is outside of these limits, which is for example an indication of a power failure, the central unit 17 will activate an alarm system as is shown in step 110.
Alternatively, the communication device 16 in the RTU 12 may be a light communicator and the opto-coupler 21 transmits the light signal on a fibre-optic line directly to the central unit 17.
In the preferred embodiment of the invention the isolation element is an opto-coupler and is connected to a communication device of a SCADA system which transmits the information to the central computer of the
SCADA system.
Using a digital conversion of the high voltage line and isolating the high voltage lines from the processing circuits preserve the original characteristic of the measured high voltage lines such as bandwidth and harmonic. Furthermore, with the use of non magnetic components such as A/D and opto-couplers and by applying floating power to the signal conversion circuit, an inexpensive electronic circuit for measuring AC high voltage characterise in that, wide bandwidth and non harmonic distortion is provided.
In the preferred embodiment of the invention, the electronic circuit is used for AC power analysis. The AC power analysis provides a measurement and calculation of the AC high voltage line parameters such as KVA, KW, KQ and power factor of the load equipment. Furthermore, the AC analysis can provide end of interval demand prediction, phase loss, power quality, and other measurements may be made directly. Data samples of the high voltage line can be held in memory and harvested later for use for example in reports.
Thus an electronic circuit and method of operation are provided for measuring AC high voltage transmission lines which mitigate at least some of the disadvantages associated with prior art arrangements.
Claims (14)
1. An electronic circuit for processing high voltage transmission line information comprising:
a signal conversion circuit operating at a first potential and operably coupled to at least one high voltage transmission line, for converting information on at least one line parameter of a high voltage transmission line into a processable format;
an isolating device operably coupled to the signal conversion circuit for transferring information on the at least one line parameter from the signal conversion circuit to a processing circuit; and
a processing circuit at a second potential for processing the at least one line parameter information from the signal conversion circuit at a second potential dissimilar to the first potential.
2. An electronic circuit according to claim 1, wherein the isolating device is an opto-coupler.
3. An electronic circuit according to claims 1 or 2, wherein the first potential is a line potential of the at least one high voltage transmission line and the second potential is a ground potential.
4. An electronic circuit as claimed in claims 1, 2 or 3 wherein the signal conversion circuit comprises:
an adapter having an input operably coupled to the high voltage transmission line; and
a first converter having an input connected to the output of the adapter and an output connected to the isolating device for converting information on at least one line parameter of a high voltage transmission line into a processable format.
5. An electronic circuit as claimed in any one of the preceding claims, wherein the processing circuit comprises:
a processing device operably coupled to the output of the isolating device via a second converter.
6. An electronic circuit as claimed in any one of the preceding claims, wherein the processing circuit is powered by a power supply having a ground potential and the signal conversion circuit is powered by a DC to DC converter having a floating potential, which is operably coupled via a transformer to the power supply.
7. An electronic circuit as claimed in any one of the preceding claims, wherein the adapter is an attenuator and the information includes at least one of voltage, phase.
8. An electronic circuit as claimed in any one of in any one of claims 1 to 6, wherein the adapter is a shunt and the information is current.
9. A method for processing high voltage transmission line information, comprising the steps of:
converting the information on at least one line parameter of a high voltage transmission line into a processable format using a signal conversion circuit;
transferring the processable format information to the processing circuit via a non magnetic isolator device; and
processing the processable format information using the microprocess or to provide a information of a line parameter.
10. A method as claimed in claim 9, wherein the line parameter is at least one of: voltage, current, phase.
11. A method as claimed in claim 9 or 10, wherein the non magnetic isolator device is an opto-coupler.
12. An alarm and control system for processing high voltage transmission line information comprising:
a master control unit for controlling at least one high voltage transmission line;
at least one remote terminal unit operably coupled to the master control unit for monitoring the at least one high voltage transmission line wherein the at least one remote terminal unit comprises:
an electronic circuit for processing high voltage transmission
line information to obtain line parameter information as claimed in
claim 1, operably coupled to the at least one high voltage transmission line; and
communication means operably coupled to the electronic circuit for transmitting the line parameter information to the master control unit.
13. An electronic circuit substantially as hereinbefore described with reference to, and or as illustrated by, FIG. 2 of the drawings.
14. A method of processing high voltage transmission line information substantially as hereinbefore described with reference to, and or as illustrated by, FIG. 3 of the drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9702120A GB2321713A (en) | 1997-02-01 | 1997-02-01 | High-voltage transmission line data transfer system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9702120A GB2321713A (en) | 1997-02-01 | 1997-02-01 | High-voltage transmission line data transfer system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB9702120D0 GB9702120D0 (en) | 1997-03-26 |
| GB2321713A true GB2321713A (en) | 1998-08-05 |
Family
ID=10806971
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9702120A Withdrawn GB2321713A (en) | 1997-02-01 | 1997-02-01 | High-voltage transmission line data transfer system |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2321713A (en) |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007045682A1 (en) * | 2005-10-21 | 2007-04-26 | Areva T & D Uk Limited | A sampling module and a method of sampling one or more analogue characteristics of a power transmission system |
| WO2009120537A1 (en) | 2008-03-26 | 2009-10-01 | Enphase Energy, Inc. | Method and apparatus for measuring ac voltages |
| WO2012059216A3 (en) * | 2010-11-02 | 2012-07-05 | Mf Instruments Gmbh | Measurement device with galvanic separation by laser |
| WO2012146923A1 (en) * | 2011-04-27 | 2012-11-01 | Northern Design (Electronics) Limited | Galvanically solated voltage measurement |
| CN103472291A (en) * | 2013-08-29 | 2013-12-25 | 国家电网公司 | Data acquiring system of high-speed high-precision high-isolation voltage |
| WO2014127788A1 (en) * | 2013-02-25 | 2014-08-28 | Isabellenhütte Heusler Gmbh & Co. Kg | Measuring system having several sensors and having a central evaluating unit |
| EP3330721A1 (en) * | 2016-12-02 | 2018-06-06 | General Electric Technology GmbH | Sensing device for switchgear and transmission line |
| CN108614142A (en) * | 2018-04-28 | 2018-10-02 | 宁波三星医疗电气股份有限公司 | A kind of improved electric power terminal |
| WO2020072337A1 (en) * | 2018-10-02 | 2020-04-09 | Rosemount Inc. | Electrical power generation or distribution asset monitoring |
| US10794736B2 (en) | 2018-03-15 | 2020-10-06 | Rosemount Inc. | Elimination of floating potential when mounting wireless sensors to insulated conductors |
| US11067639B2 (en) | 2017-11-03 | 2021-07-20 | Rosemount Inc. | Trending functions for predicting the health of electric power assets |
| US11181570B2 (en) | 2018-06-15 | 2021-11-23 | Rosemount Inc. | Partial discharge synthesizer |
| US11313895B2 (en) | 2019-09-24 | 2022-04-26 | Rosemount Inc. | Antenna connectivity with shielded twisted pair cable |
| US11448682B2 (en) | 2017-03-02 | 2022-09-20 | Rosemount Inc. | Trending functions for partial discharge |
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1997
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| GB1533072A (en) * | 1976-06-21 | 1978-11-22 | Int Standard Electric Corp | Compensated signal isolator for measurements in high voltage environments |
| GB2010499A (en) * | 1977-12-13 | 1979-06-27 | Central Electr Generat Board | Measuring High Voltages Using Opto-Isolation |
| US4374359A (en) * | 1979-10-04 | 1983-02-15 | IREQ--Institut de Recherche de l'Hydro-Quebec | System and method of sensing current in high voltage transmission lines utilizing the transmission of digital information by optical fibers |
| US4449244A (en) * | 1981-03-05 | 1984-05-15 | Bbc Brown, Boveri & Company Limited | Data transmission network employing optical wave guide |
| GB2201798A (en) * | 1987-02-26 | 1988-09-07 | Bicc Plc | Electric current measurement |
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Cited By (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7768253B2 (en) | 2005-10-21 | 2010-08-03 | Areva T&D Uk Limited | Sampling module and a method of sampling one or more analogue characteristics of a power transmission system |
| CN101292164B (en) * | 2005-10-21 | 2012-08-22 | 阿海珐输配电英国有限公司 | A sampling module and a method of sampling one or more analogue characteristics of a power transmission system |
| WO2007045682A1 (en) * | 2005-10-21 | 2007-04-26 | Areva T & D Uk Limited | A sampling module and a method of sampling one or more analogue characteristics of a power transmission system |
| EP2269079A4 (en) * | 2008-03-26 | 2014-05-21 | Enphase Energy Inc | Method and apparatus for measuring ac voltages |
| WO2009120537A1 (en) | 2008-03-26 | 2009-10-01 | Enphase Energy, Inc. | Method and apparatus for measuring ac voltages |
| EP2269079A1 (en) * | 2008-03-26 | 2011-01-05 | Enphase Energy, Inc. | Method and apparatus for measuring ac voltages |
| US9279832B2 (en) | 2008-03-26 | 2016-03-08 | Enphase Energy, Inc. | Method and apparatus for measuring AC voltages |
| WO2012059216A3 (en) * | 2010-11-02 | 2012-07-05 | Mf Instruments Gmbh | Measurement device with galvanic separation by laser |
| GB2490340B (en) * | 2011-04-27 | 2015-02-18 | Northern Design Electronics Ltd | Improvements in and relating to voltage measurement |
| WO2012146923A1 (en) * | 2011-04-27 | 2012-11-01 | Northern Design (Electronics) Limited | Galvanically solated voltage measurement |
| AU2012247306B2 (en) * | 2011-04-27 | 2016-12-01 | Northern Design (Electronics) Limited | Galvanically solated voltage measurement |
| WO2014127788A1 (en) * | 2013-02-25 | 2014-08-28 | Isabellenhütte Heusler Gmbh & Co. Kg | Measuring system having several sensors and having a central evaluating unit |
| CN103472291A (en) * | 2013-08-29 | 2013-12-25 | 国家电网公司 | Data acquiring system of high-speed high-precision high-isolation voltage |
| EP3330721A1 (en) * | 2016-12-02 | 2018-06-06 | General Electric Technology GmbH | Sensing device for switchgear and transmission line |
| US11448682B2 (en) | 2017-03-02 | 2022-09-20 | Rosemount Inc. | Trending functions for partial discharge |
| US11067639B2 (en) | 2017-11-03 | 2021-07-20 | Rosemount Inc. | Trending functions for predicting the health of electric power assets |
| US10794736B2 (en) | 2018-03-15 | 2020-10-06 | Rosemount Inc. | Elimination of floating potential when mounting wireless sensors to insulated conductors |
| CN108614142A (en) * | 2018-04-28 | 2018-10-02 | 宁波三星医疗电气股份有限公司 | A kind of improved electric power terminal |
| US11181570B2 (en) | 2018-06-15 | 2021-11-23 | Rosemount Inc. | Partial discharge synthesizer |
| US10833531B2 (en) | 2018-10-02 | 2020-11-10 | Rosemount Inc. | Electric power generation or distribution asset monitoring |
| WO2020072337A1 (en) * | 2018-10-02 | 2020-04-09 | Rosemount Inc. | Electrical power generation or distribution asset monitoring |
| US11313895B2 (en) | 2019-09-24 | 2022-04-26 | Rosemount Inc. | Antenna connectivity with shielded twisted pair cable |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9702120D0 (en) | 1997-03-26 |
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