CN113238081A - Intelligent electric meter terminal - Google Patents
Intelligent electric meter terminal Download PDFInfo
- Publication number
- CN113238081A CN113238081A CN202110563832.4A CN202110563832A CN113238081A CN 113238081 A CN113238081 A CN 113238081A CN 202110563832 A CN202110563832 A CN 202110563832A CN 113238081 A CN113238081 A CN 113238081A
- Authority
- CN
- China
- Prior art keywords
- meter terminal
- mcu
- smart meter
- sensor
- interface
- 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.)
- Pending
Links
- 238000004891 communication Methods 0.000 claims abstract description 34
- 238000005070 sampling Methods 0.000 claims abstract description 22
- 238000005259 measurement Methods 0.000 claims description 10
- 239000013078 crystal Substances 0.000 claims description 6
- 230000005540 biological transmission Effects 0.000 claims description 4
- 230000005059 dormancy Effects 0.000 claims 1
- 238000013461 design Methods 0.000 abstract description 29
- 238000011160 research Methods 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 230000018109 developmental process Effects 0.000 description 3
- 230000002457 bidirectional effect Effects 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000001012 protector Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000033772 system development Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R11/00—Electromechanical arrangements for measuring time integral of electric power or current, e.g. of consumption
- G01R11/02—Constructional details
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R22/00—Arrangements for measuring time integral of electric power or current, e.g. electricity meters
- G01R22/06—Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
- G01R22/061—Details of electronic electricity meters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R22/00—Arrangements for measuring time integral of electric power or current, e.g. electricity meters
- G01R22/06—Arrangements for measuring time integral of electric power or current, e.g. electricity meters by electronic methods
- G01R22/061—Details of electronic electricity meters
- G01R22/063—Details of electronic electricity meters related to remote communication
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Arrangements For Transmission Of Measured Signals (AREA)
Abstract
The invention provides an intelligent electric meter terminal, which comprises: the device comprises a core board, an expansion board and an external sensor; the expansion board is connected with the core board through a GEC interface, and the expansion board is connected with the external sensor through a universal interface; the core board comprises an MCU and a communication module connected with the MCU through a fixed interface; the expansion board comprises a photosensitive sensor, a thermosensitive sensor, a program downloading interface, a power interface and a working indicator light; the external sensor comprises an LCD display and a power grid data sampling sensor. The invention researches the design idea of embedded hardware and finally designs the AHL NB-IoT-based electric meter terminal. The electric meter terminal adopts the design idea of hardware circuit modularization, and the hardware circuit can be rapidly multiplexed. The hardware entity adopts a component design idea, and the hardware terminal can be rapidly upgraded.
Description
Technical Field
The invention belongs to the field of intelligent electric meters, and particularly relates to an AHL NB-IoT-based intelligent electric meter terminal.
Background
The electric energy meter technology in China has more than 70 years of history up to now. In 1952, Shanghai and adult electrical equipment factories started to produce electric energy meters professionally, and at the moment, the electric energy meters imitating foreign induction systems were mainly used. In the early 60 s, China began to design electric energy meters by oneself. In the middle and later 70 s, the manufacturing technology of foreign advanced electric energy meters is introduced. In the early 90 s, the domestic electronic electric energy meter was successfully developed. In recent years, power grid assets and services are continuously digitalized, the technology of the internet of things is gradually deeply integrated with the power equipment sensing technology, the system of the internet of things of power grid equipment begins to appear, and information begins to be interconnected and intercommunicated.
The intelligent electric meter is an intelligent terminal of an intelligent power grid, has the functions of bidirectional multi-rate metering, user side control, bidirectional data communication in multiple data transmission modes, electricity larceny prevention and other intelligent functions in order to adapt to the use of the intelligent power grid and new energy besides the metering function of basic electricity consumption of the traditional electric meter, and represents the development direction of future intelligent terminals of end users of the energy-saving intelligent power grid. The existing network development is gradually improved, but the existing integrated design idea terminal needs to be manufactured again when local circuits are upgraded, so that the design speed is slow and the cost is high.
Disclosure of Invention
The purpose of the invention is realized by the following technical scheme.
The invention provides an intelligent electric meter terminal, which comprises:
the device comprises a core board, an expansion board and an external sensor; the expansion board is connected with the core board through a GEC interface, and the expansion board is connected with the external sensor through a universal interface;
the core board comprises an MCU and a communication module connected with the MCU through a fixed interface;
the expansion board comprises a photosensitive sensor, a thermosensitive sensor, a program downloading interface, a power interface and a working indicator light;
the external sensor comprises an LCD display and a power grid data sampling sensor.
Further, the power grid data sampling sensor adopts an HT7036 metering chip.
Further, the MCU adopts an STM32L431 chip.
Further, the communication module adopts an ME3616 communication module.
Furthermore, the MCU communicates with the external sensor through the SPI module, acquires acquired data, sends the data to the communication module through the serial port, and the communication module uploads the data to the cloud server through narrow-band transmission.
Further, the MCU is in serial port communication with an upper computer calibration program, the gain parameters stored in the MCU are calibrated, and the calibrated gain parameters are written into the metering chip through SPI communication.
Furthermore, a reset pin of the metering chip is externally connected with a high level, a sleep mode control pin of the metering chip keeps a low level, and a connecting pin of an external crystal oscillator of the metering chip is connected with an 5.5296MHz crystal oscillator.
Further, the smart meter terminal further comprises a calibration circuit, and the calibration circuit comprises two current transformers.
Further, the SPI module is an SPI low pass filter circuit.
Further, the smart meter terminal further comprises a surge protection circuit.
The invention has the advantages that: the invention researches the design idea of embedded hardware and finally designs the AHL NB-IoT-based electric meter terminal. The electric meter terminal adopts the design idea of hardware circuit modularization, and the hardware circuit can be rapidly multiplexed. The hardware entity adopts a component design idea, and the hardware terminal can be rapidly upgraded.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
fig. 1 is a diagram showing a hardware configuration and basic functions of a terminal according to an embodiment of the present invention.
Fig. 2 shows a calibration circuit diagram according to an embodiment of the invention.
Fig. 3 shows a voltage sampling circuit diagram according to an embodiment of the invention.
Fig. 4 shows a current sampling circuit diagram according to an embodiment of the invention.
FIG. 5 shows a diagram of an SPI low pass filter circuit according to an embodiment of the invention.
Detailed Description
Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
1.1 Embedded hardware design analysis
The circuit design aiming at specific hardware pins is suitable for the current hardware entity; aiming at the design of hardware functions, a hardware circuit can be quickly transplanted, and the design idea of embedded hardware modularization is met. And calculating the board manufacturing cost of the embedded terminal by taking the area as a unit. Compared with an integrated large-area terminal, the hardware terminal designed by adopting the small-area splicing idea is lower in cost. The terminal is limited by specific installation environment, the size and the maximum surface area are small and large-scale, and the small-area and splicing design can adapt to various installation environments. The integrated design idea terminal needs to be manufactured again when local circuits are upgraded; and the spliced terminal only needs to be manufactured again for the upgrading part. The small-area spliced circuit is reasonably planned, so that each part of hardware can become an independent hardware component with a minimum functional module and inseparability, and the hardware component can build terminals with different functions in various combination modes.
The external sensor mainly comprising the HT7036 electric energy metering chip uses external wiring, communicates with the MCU through the SPI function pin, and shares the power supply of the MCU. When the sensor is replaced, only the wiring needs to be changed, and the plate does not need to be manufactured again. If the current SPI module has problems, other SPI modules of the MCU can be connected. When the MCU is upgraded at the later stage of the electric meter terminal, only the circuit design of the core board needs to be changed, and the circuit design of the communication pin does not need to be changed.
1.2 terminal hardware architecture composition
The terminal mainly controls LCD display through an SPI protocol, communicates with the metering chip, acquires power grid data such as voltage, current and power collected by the metering chip, realizes passive calibration through cooperation of a UART protocol and a calibration program, and communicates with the narrow-band communication module to realize data uploading. The electric energy quality acquisition terminal mainly comprises MCU minimum system and expansion board interface circuit, external sensor circuit, communication module circuit etc. that use HT7036 to measure the chip and give first place to, terminal hardware component constitutes as shown in figure 1 below, includes: the device comprises a core board, an expansion board and an external sensor; the expansion board is connected with the core board through a GEC interface, and the expansion board is connected with the external sensor through a universal interface; the core board comprises an MCU and a communication module connected with the MCU through a fixed interface; the expansion board comprises a photosensitive sensor, a thermosensitive sensor, a program downloading interface, a power interface and a working indicator light; the external sensor comprises an LCD display and a power grid data sampling sensor.
The power grid data sampling sensor adopts an HT7036 metering chip. The MCU adopts an STM32L431 chip. The external sensor taking the HT7036 metering chip as a main part is responsible for collecting power grid data, and the STM32L431 chip is communicated with the external sensor through the SPI module to obtain collected data. And then, the data is sent to an ME3616 communication module through a serial port, and the communication module uploads the data to a cloud server through narrow-band transmission. And the communication module receives the data sent back by the cloud server and feeds back the data to the STM32L431 main control chip. Before starting to measure data, the STM32L431 main control chip needs to communicate with an upper computer calibration program through a serial port to calibrate the gain parameters stored in the main control chip, and writes the calibrated gain parameters into the metering chip through SPI communication.
The core board of the electric meter terminal adopts a double-sided design, the back side is an MCU minimum system, and the front side is a communication module. The MCU and the communication module are arranged on the front side and the back side of the core board, hardware coupling is reduced, and the cost of MCU and communication module iteration can be effectively reduced.
The expansion board is mainly provided with a photosensitive resistor, a thermistor, a magnetic resistance and various sensor interfaces.
The external sensors for monitoring the power quality are all of SPI communication type, and comprise a liquid crystal screen for displaying terminal information and an external sensor for collecting power data, and the physical diagrams of the external sensors are shown in the following figures 3-5. The external sensor is connected with the expansion board through a sensor interface. The external sensor is used as a hardware component and is externally connected according to the interface, so that the hardware upgrading of the electric meter terminal is facilitated.
The LCD display interface of the terminal is divided into five parts, the terminal has a uniform name area, and the content is AHL NB-IoT PQM. And the terminal basic information area comprises an IMSI number, a chip temperature and terminal program version information. And the sending configuration information area comprises the IP address, the port number, the signal strength, the sending frequency and the like of the cloud server. And the electric energy data information area comprises current voltage power. And a terminal operation state prompting area is used for prompting a calibration result, a data sending result and the like.
1.3 terminal Circuit design
The terminal circuit mainly comprises a calibration circuit, a voltage and current sampling circuit, an MCU and metering chip communication circuit and a terminal protection circuit. The latter three are indispensable parts of the terminal working circuit, and the calibration circuit is responsible for testing and calibrating the terminal so as to ensure the accuracy of the terminal measurement data.
1.3.1 calibration Circuit design
The calibration circuit includes two current transformers. In passive calibration, A, B, C three-phase data are respectively calibrated. An alternating current voltage stabilizing source is used for connecting 220V stable voltage to the metering chip, a load area terminal is used for supplying power to the pure resistance load, and the current transformer is connected to the same-phase current terminal. And calibrating by using a program according to the current, voltage and power data displayed by the terminal screen. During voltage, current and power calibration, the load is changed into a slide rheostat with a power factor of 1, so that after the calibration is successful, the current and the voltage of the board are changed, and the error of the power grid data is determined. The calibration circuit is shown in fig. 2 below.
1.3.2 sampling Circuit design
The voltage and current sampling circuit is realized by a 19-bit ADC module in an HT7036 chip and adopts double-end differential signal input.
1. Voltage sampling circuit
And the voltage measurement is realized by adopting a series voltage division principle. Taking the phase a measurement circuit as an example, R213 to R219 serve as voltage dividing resistors, and the voltage across R220 is the same as the input voltage of the channel a of the measurement chip. U shapeAThe pin is connected with an A-phase live wire through a voltage terminal, the other end of the pin is connected with a positive analog input pin and a negative analog input pin (V2P and V2N) of an A-phase voltage channel, and the input effective value of the voltage channel is about 0.22V. In calibration, the voltage channel input value is about 0.114V, and the ADC gain configuration registers bit9 and bit8 are set to 01, so that the voltage channel gain multiple can be set to 2, and the target input voltage is achieved. The full-scale effective value of the ADC channel is 0.5V, and the voltage range of the input plate is 0-481.5V under the 2-time gain mode. The voltage sampling circuit design is shown in figure 3 below.
2. Current sampling circuit
The current sampling is realized by a ZHT103U type current transformer, the transformation ratio of the current transformer is 1000:1, and the board-entering current is an actual circuit 1/1000. The input effective value of the current channel ADC is about 0.05V, a 100 omega slide rheostat is used, the resistance value is set to 69 omega, and when the mains supply is supplied, about 3.2A of current can be generated. Current is accessed to the metering chip through the mutual inductor, the gain coefficient of the metering chip is set to be 2, the input voltage of the current sampling channel reaches 49.76mV, and correct current gain value is easy to obtain by calibrating in the mode. The current sampling circuit is shown in fig. 4 below.
1.3.3MCU and metering chip communication circuit design
The metering chip is connected with the pins of the expansion board in the form of an external sensor through DuPont wires. The communication pin of measurement chip links to each other with STM32L 431's SPI module function pin, realizes the communication between MCU and the measurement chip. The sampling circuit and the communication circuit realize the filtering of high-frequency signals by introducing a low-pass filter circuit, and the maximum frequency calculation formula which can be passed by the filter circuit is as follows:
the SPI communication interface rate of the metering chip can reach 10Mbps, high-frequency noise far higher than 10MHz can be filtered by using the combination of 100R and 100PF resistors and capacitors, and the communication circuit of the MCU and the metering chip 1 is shown in a figure 5.
1.3.4 Surge protection Circuit design
The current sampling circuit uses a current transformer, the generated current is in mA level and far lower than a rated value, and the surge phenomenon is not easy to generate. A voltage limiting type surge protector is introduced into a voltage sampling circuit to form a surge protection circuit, the voltage sampling circuit needs to be connected with MYN23-681K type piezoresistors in parallel, and when surge voltage occurs, the impedance of the piezoresistors is continuously reduced, the surge voltage is absorbed, and terminal equipment is protected. In order to prevent the overcurrent phenomenon of the terminal circuit, a PTC thermistor is connected in series with the live wire. The PTC thermistor has the characteristic of low-temperature conduction, the resistance value of the PTC thermistor is rapidly increased along with the rise of temperature, and the PTC thermistor can play a role in overload protection.
1.3.5 metrology chip minimum system circuit design
The metering chip minimum system is a minimum circuit unit in which the metering chip can normally operate, and the HT7036 metering chip is used for collecting power grid data. The RESET pin (No. 1, RESET pin) of the metering chip must be externally connected with a high level (3.3V) to ensure the normal work of the metering chip. The SLEEP mode control pin (No. 22, SLEEP pin) of the metering chip must be kept low to ensure that the chip is in a normal operating mode. The connection pin (No. 30, OSCI pin; No. 31, OSCO pin) of the external crystal oscillator of the metering chip must be connected with the 5.5296MHz crystal oscillator to ensure the measurement precision of the metering chip to the maximum extent.
The invention mainly explains the calibration circuit and the external sensor circuit related in the power quality monitoring system in detail. The correct hardware circuit design is the basis of the development of an embedded software system, a reasonable hardware architecture provides convenience for the upgrade of the system, and the hardware cost of the system development is reduced. A hardware system based on an AHL NB-IoT architecture provides theoretical support for embedded hardware component design.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (10)
1. A smart meter terminal, comprising:
the device comprises a core board, an expansion board and an external sensor; the expansion board is connected with the core board through a GEC interface, and the expansion board is connected with the external sensor through a universal interface;
the core board comprises an MCU and a communication module connected with the MCU through a fixed interface;
the expansion board comprises a photosensitive sensor, a thermosensitive sensor, a program downloading interface, a power interface and a working indicator light;
the external sensor comprises an LCD display and a power grid data sampling sensor.
2. The smart meter terminal as claimed in claim 1,
the power grid data sampling sensor adopts an HT7036 metering chip.
3. The smart meter terminal as claimed in claim 1,
the MCU adopts an STM32L431 chip.
4. The smart meter terminal as claimed in claim 1,
the communication module adopts an ME3616 communication module.
5. The smart meter terminal as claimed in claim 1,
the MCU communicates with the external sensor through the SPI module, acquires acquired data, sends the data to the communication module through the serial port, and the communication module uploads the data to the cloud server through narrow-band transmission.
6. The smart meter terminal according to claim 2,
the MCU is communicated with an upper computer calibration program through a serial port, the gain parameters stored in the MCU are calibrated, and the calibrated gain parameters are written into the metering chip through SPI communication.
7. The smart meter terminal as claimed in claim 6,
the external high level of reset pin of measurement chip, the dormancy mode control pin of measurement chip keeps the low level, and the connecting pin of measurement chip outside crystal oscillator links to each other with 5.5296MHz crystal oscillator.
8. The smart meter terminal as claimed in claim 1,
the smart meter terminal further comprises a calibration circuit, and the calibration circuit comprises two current transformers.
9. The smart meter terminal as claimed in claim 5,
the SPI module is an SPI low-pass filter circuit.
10. The smart meter terminal as claimed in claim 1,
the intelligent electric meter terminal further comprises a surge protection circuit.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110563832.4A CN113238081A (en) | 2021-05-24 | 2021-05-24 | Intelligent electric meter terminal |
| PCT/CN2021/121568 WO2022247089A1 (en) | 2021-05-24 | 2021-09-29 | Smart electricity meter terminal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110563832.4A CN113238081A (en) | 2021-05-24 | 2021-05-24 | Intelligent electric meter terminal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113238081A true CN113238081A (en) | 2021-08-10 |
Family
ID=77138400
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110563832.4A Pending CN113238081A (en) | 2021-05-24 | 2021-05-24 | Intelligent electric meter terminal |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN113238081A (en) |
| WO (1) | WO2022247089A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022247087A1 (en) * | 2021-05-24 | 2022-12-01 | 苏州大学 | Electric energy quality monitoring system of smart meter |
| WO2022247089A1 (en) * | 2021-05-24 | 2022-12-01 | 苏州大学 | Smart electricity meter terminal |
| CN119619619A (en) * | 2024-12-04 | 2025-03-14 | 浙江炬芯微电子有限公司 | A three-phase electric energy meter data acquisition communication unit |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202584509U (en) * | 2011-09-26 | 2012-12-05 | 聂章龙 | Freescale HCS12 series one-chip microcomputer teaching experimental instrument |
| US20140167977A1 (en) * | 2012-12-17 | 2014-06-19 | Itron, Inc. | System on a Module for Smart Grid Nodes |
| CN106872737A (en) * | 2015-12-11 | 2017-06-20 | 上海紫西实业有限公司 | Electrical energy data acquiring terminal based on dsPIC |
| CN108808854A (en) * | 2018-06-06 | 2018-11-13 | 广东电网有限责任公司 | A kind of electric distribution network data collection terminal based on intelligent terminal |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202084993U (en) * | 2011-05-17 | 2011-12-21 | 中国电力科学研究院 | A standard intelligent distribution transformer terminal |
| CN107786672A (en) * | 2017-11-16 | 2018-03-09 | 积成电子股份有限公司 | Support the ammeter data acquisition terminal of DLMS/COSEM agreements |
| CN113176466A (en) * | 2021-05-24 | 2021-07-27 | 苏州大学 | Electric energy quality monitoring system of intelligent electric meter |
| CN113238081A (en) * | 2021-05-24 | 2021-08-10 | 苏州大学 | Intelligent electric meter terminal |
-
2021
- 2021-05-24 CN CN202110563832.4A patent/CN113238081A/en active Pending
- 2021-09-29 WO PCT/CN2021/121568 patent/WO2022247089A1/en active Application Filing
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202584509U (en) * | 2011-09-26 | 2012-12-05 | 聂章龙 | Freescale HCS12 series one-chip microcomputer teaching experimental instrument |
| US20140167977A1 (en) * | 2012-12-17 | 2014-06-19 | Itron, Inc. | System on a Module for Smart Grid Nodes |
| CN106872737A (en) * | 2015-12-11 | 2017-06-20 | 上海紫西实业有限公司 | Electrical energy data acquiring terminal based on dsPIC |
| CN108808854A (en) * | 2018-06-06 | 2018-11-13 | 广东电网有限责任公司 | A kind of electric distribution network data collection terminal based on intelligent terminal |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022247087A1 (en) * | 2021-05-24 | 2022-12-01 | 苏州大学 | Electric energy quality monitoring system of smart meter |
| WO2022247089A1 (en) * | 2021-05-24 | 2022-12-01 | 苏州大学 | Smart electricity meter terminal |
| CN119619619A (en) * | 2024-12-04 | 2025-03-14 | 浙江炬芯微电子有限公司 | A three-phase electric energy meter data acquisition communication unit |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2022247089A1 (en) | 2022-12-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113238081A (en) | Intelligent electric meter terminal | |
| CN111239481A (en) | Intelligent metering terminal of agricultural water | |
| CN104330621A (en) | Electric appliance energy consumption tester | |
| CN212905201U (en) | Automatic power consumption test circuit of electronic product | |
| CN206638708U (en) | A kind of three-phase power parameter real time monitoring system | |
| CN103293362B (en) | DC ammeter and multimeter and apply the measuring method of this reometer or multimeter | |
| CN211717670U (en) | Automatic calibrator for temperature transmitter | |
| CN210720558U (en) | Low-cost portable voltage measurement device | |
| CN209707606U (en) | A kind of blood glucose meter detection device | |
| CN217587363U (en) | Electric parameter detection circuit and electric quantity isolation transmitter | |
| CN103278676A (en) | Electric current true virtual value detection circuit of electromotor soft starter | |
| CN203433041U (en) | An electric energy meter provided with a communication function | |
| CN107707276B (en) | Power consumption detection device based on broadband power line carrier communication unit | |
| CN102096458B (en) | Digital power supply and external display device connected with same | |
| CN206004290U (en) | A kind of home circuit electric current monitor | |
| CN87208972U (en) | Intelligent multi-channel temperature measurer | |
| CN114002491A (en) | Zero point detection circuit and clutter detection system | |
| CN201290068Y (en) | Terminal for monitoring power supply environment | |
| CN205003267U (en) | But error compensation's voltmeter | |
| CN220271423U (en) | A practical multi-channel signal analyzer | |
| CN222125337U (en) | Multifunctional electric power instrument with Internet of things and temperature measurement functions | |
| CN222689822U (en) | A three-phase power analysis circuit | |
| CN218381336U (en) | Instrument for measuring extremely low temperature | |
| CN221667114U (en) | Temperature detection circuit, circuit board and electronic equipment | |
| CN221959657U (en) | Signal acquisition circuit for array resistance type pressure sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210810 |
|
| RJ01 | Rejection of invention patent application after publication |