A connecting device for an electric energy meter circuit board

Abstract

The utility model discloses a kind of connecting devices for electric energy meter circuit board, comprising: integrated PCB structure and L-shaped strong electricity partition.Integrated PCB structure contains left side plate, upper plate, right side plate and bottom plate, each board is electrically connected by copper foil circuit, without interconnector;Left side plate is equipped with main control chip and peripheral circuit, upper plate is equipped with display, indication and key component, right side plate is equipped with power module and conversion circuit, bottom plate is designed with area, sampling circuit and weak signal connection device etc.L-shaped strong electricity partition is made of right side plate and bottom plate lower area, strong electricity module is concentrated here, and keep preset electrical clearance and creepage distance with weak electricity area.Digital isolation chip is equipped between left side plate and bottom plate lower area, power module is powered for each component through conversion circuit, and the device is also integrated with leakage detection, remote communication and other functions.The device simplifies structure, reduces interference, improves operation stability and power supply adaptability, meets the multifunctional demand of intelligent electric energy meter.

Description

Technical Field

[0001] This utility model relates to the field of power equipment technology, and in particular to a connection device for a circuit board of an electricity meter. Background Technology

[0002] In the field of electricity metering, electricity meters, as core equipment, need to integrate multiple functions such as voltage and current sampling, data processing, display, and communication. The stability, integration, and security of their circuit board connection devices directly affect the overall performance of the meter. With the development of smart grids, electricity meters need to adapt to the electricity monitoring needs of multiple scenarios. They not only need to accurately measure electricity but also support extended functions such as remote communication, leakage current detection, and rate switching. This places higher demands on the layout and connection of the various modules on the circuit board. Currently, electricity meter circuit boards often need to integrate power supply modules, metering modules, main control modules, display modules, and external interfaces. Reliable electrical connections between these modules are required to ensure data transmission and stable power supply. At the same time, it is necessary to separate high-voltage and low-voltage areas to avoid signal interference and ensure electricity safety and metering accuracy. Therefore, the structural design and functional integration of the circuit board connection devices have become key aspects of electricity meter research and development.

[0003] Existing technologies for electricity meter circuit board connection devices have two significant drawbacks. Firstly, some devices employ a design of multiple independent PCB boards spliced ​​together, requiring connectors for electrical connection. This structure not only increases the overall size and assembly complexity of the device but also makes it prone to power outages or data transmission anomalies due to poor connector contact, reducing operational stability. Furthermore, the splicing of multiple boards results in a dispersed circuit layout, hindering effective isolation between high-voltage and low-voltage areas and easily leading to signal interference. Secondly, some devices have deficiencies in signal transmission and power supply design. The lack of reliable isolation measures between high-voltage and low-voltage areas causes high-voltage signals to interfere with low-voltage signals, affecting the data transmission accuracy between the metering chip and the main control chip. Moreover, some devices are not optimized for the power supply requirements of different functional modules; a single power output cannot adapt to the differentiated power supply requirements of multiple modules, easily leading to unstable power supply to some modules, thus affecting the overall functionality of the electricity meter. Utility Model Content

[0004] In order to overcome the shortcomings and deficiencies of the existing technology, this utility model provides a connection device for the circuit board of an electricity meter.

[0005] The technical solution adopted in this utility model is a connection device for a circuit board of an electricity meter, comprising an integrated PCB structure and an L-shaped high-voltage partition. The integrated PCB structure includes a left side plate, a top plate, a right side plate, and a bottom plate. The left side plate houses the main control chip and its core peripheral circuits. The top plate houses an LCD screen, status indicator LEDs, and buttons. The right side plate houses a 220VAC / DC power module and a secondary power conversion circuit. The lower area of ​​the bottom plate houses a metering chip, a voltage sampling circuit, and a current sampling circuit. The upper area of ​​the bottom plate houses a low-voltage signal connection device for external connection. The left side plate, top plate, right side plate, and bottom plate are electrically connected as a whole through copper foil lines on the PCB, without inter-board connectors. The L-shaped high-voltage partition is formed by the right side plate and the lower area of ​​the bottom plate. The right side plate houses the 220VAC / DC power module and its secondary power conversion circuit, and the lower area of ​​the bottom plate houses the metering chip. The voltage sampling circuit and current sampling circuit are both located within the L-shaped high-voltage zone. The high-voltage connection device is located at the edge of the L-shaped high-voltage zone. The low-voltage signal connection device includes RS485 communication terminals, calibration pulse output terminals, and leakage current detection signal input terminals, and is centrally arranged on the base plate area. A digital isolation chip is installed between the left side plate and the area below the base plate. The main control chip of the left side plate transmits signals to the metering chip in the area below the base plate through the digital isolation chip. The output terminal of the 220VAC / DC power module of the right side plate is connected to the LCD screen, status indicator LED, and buttons on the upper plate, the main control chip and storage circuit on the left side plate, the low-voltage signal connection device and relay drive circuit in the area above the base plate, and the metering chip and digital isolation chip in the area below the base plate via copper foil lines. The backup battery is connected to the upper plate, and the upper plate is connected to the main control chip and storage circuit on the left side plate via copper foil lines.

[0006] Furthermore, the secondary power conversion circuit on the right side panel includes a flyback power supply module and a DC-DC step-down module. The flyback power supply module converts the voltage output from the 220VAC / DC power supply module into a 12V DC voltage. One 12V DC voltage is converted into a 3.9V DC voltage by the DC-DC step-down module. The 3.9V DC voltage powers the 4G communication module, which is located on the right side panel and connected to the main control chip on the left side panel via copper foil lines. The other 12V DC voltage directly powers the LCD screen, status indicator LEDs, and buttons on the upper panel, as well as the main control chip and storage circuit on the left side panel.

[0007] Furthermore, the voltage sampling circuit in the area under the base plate includes a series resistor network. The AC voltage signal is divided by the series resistor network and converted into a weak voltage signal, which is then transmitted to the metering chip. The current sampling circuit includes a manganese copper sheet sampling resistor. The live wire current is converted into a microvolt-level voltage signal by the manganese copper sheet sampling resistor, which is then transmitted to the metering chip.

[0008] Furthermore, the relay drive circuit in the area of ​​the base plate is connected to the main control chip on the left side plate through copper foil lines. The main control chip outputs control signals to the relay drive circuit, and the relay drive circuit controls the relay to turn on and off. The calibration pulse output terminal is connected to the main control chip on the left side plate through copper foil lines. The main control chip outputs calibration pulse signals consistent with the meter constant to the calibration pulse output terminal.

[0009] Furthermore, the leakage current detection signal input terminal in the area of ​​the base plate is connected to the leakage current sampling circuit. The leakage current sampling circuit is externally connected to the residual current transformer. The leakage current sampling circuit converts the collected leakage current data into a voltage signal. The voltage signal is transmitted to the ADC detection port of the main control chip on the left side plate through the copper foil line.

[0010] Furthermore, the storage circuit on the left side panel is connected to the main control chip via an I2 bus. The main control chip stores the processed power data and time data in the storage circuit. The LCD screen on the upper panel is connected to the main control chip via an I2C bus. The main control chip outputs display data to the LCD screen, which displays the relevant data of the electricity meter operation.

[0011] Furthermore, the buttons on the upper board are connected to the main control chip on the left side board via copper foil circuitry. The main control chip detects whether a button is pressed via an external interrupt. When a button is pressed, the main control chip switches the information displayed on the LCD screen. The status indicator LEDs are connected to the main control chip via copper foil circuitry, and the main control chip controls the on / off state indicator LEDs and their blinking.

[0012] Furthermore, the PCB layout between the L-shaped high-voltage and low-voltage zones meets the preset electrical clearances and creepage distances, with electrical clearances not less than 3mm and creepage distances not less than 4mm; the 220VAC / DC power module on the right side panel adopts an isolation design with an isolation voltage not less than 2500VAC.

[0013] Furthermore, the RS485 communication terminal on the base plate is connected to the RS485 conversion circuit. The RS485 conversion circuit is connected to the serial port of the main control chip on the left side plate through copper foil lines. The main control chip interacts with external devices through the RS485 conversion circuit and the RS485 communication terminal.

[0014] Furthermore, an RTC clock circuit is also arranged on the left side panel. The RTC clock circuit is connected to the main control chip through copper foil lines. The RTC clock circuit provides a time signal to the main control chip, and the main control chip selects the corresponding rate to process the power data according to the time signal.

[0015] Beneficial Effects: This utility model proposes a connection device for the circuit board of an electricity meter. In terms of structure and stability, it adopts an integrated PCB structure. The left side board, top board, right side board, and bottom board are directly electrically connected by copper foil lines, eliminating the need for inter-board connectors. This reduces the overall size and assembly complexity of the device and avoids power interruption or data transmission abnormalities caused by poor connector contact. At the same time, the L-shaped high-voltage partitioning concentrates the high-voltage modules in the area under the right side board and bottom board. With the preset electrical clearance and creepage distance, it effectively isolates the high-voltage and low-voltage areas, solving the signal interference problem caused by the scattered circuits of multiple boards. In terms of function and power supply, the secondary power conversion circuit can convert the output voltage according to the needs of different modules, adapting to the differentiated power supply requirements of multiple modules and avoiding power instability caused by a single power output. The digital isolation chip further ensures the signal transmission accuracy between the high-voltage and low-voltage areas. The integration of extended functions such as leakage detection and 4G communication meets the monitoring needs of multiple scenarios of smart grids. Moreover, the orderly connection of each module through copper foil lines ensures stable data transmission and power supply, comprehensively improving the overall performance and reliability of the electricity meter. Attached Figure Description

[0016] Figure 1 This is a PCB structure diagram of the connecting device of this utility model;

[0017] Figure 2 This is the L-shaped high-voltage zoning diagram of this utility model;

[0018] Figure 3 This is a functional structural diagram of the present invention. Detailed Implementation

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] like Figure 1 As shown, a connection device for an electricity meter circuit board is disclosed. The meter structure consists of a left side plate (① in the figure), a top plate (② in the figure), a right side plate (③ in the figure), and a bottom plate (④ in the figure). The layers are electrically interconnected through copper foil pads between the boards, forming a compact, stable whole that requires no external pin headers. Compared with external wires or pin headers, this connection method has the advantages of lower impedance, higher reliability, and stronger vibration resistance.

[0021] Power circuit connection: The 220V high-voltage terminal wires (L and N) are connected to the base PCB, and converted to approximately 310V DC power by the rectifier bridge circuit (㉕ in the figure). This DC power then enters the right side board via the connector between the base board (④ in the figure) and the right side board (③ in the figure), and is converted into two isolated approximately 12V DC power supplies (⑮ in the figure) via the flyback power module (⑮ in the figure) (⑪ and ⑫ in the figure). The 12V power supply in line 1 enters the base board via the connector between the base board and the right side board, and then powers the digital isolation chip (⑳ in the figure) and the metering chip (㉒ in the figure) via the 12V to 3.3V power module (㉑ in the figure). In Line 2, the 12V power supply is converted to approximately 3.9V VMODE via a DC-DC step-down module (⑭ in the diagram) to power the 4G communication module (⑬ in the diagram); another path passes through the connector between the upper board (② in the diagram) and the right side board (③ in the diagram) to power the buttons (⑥ in the diagram), LED indicators (⑦ in the diagram), and LCD screen (⑧ in the diagram); another path passes through the connector between the upper board and the left side board (① in the diagram) to power the MCU (⑤ in the diagram) and EEPROM storage (㉖ in the diagram) circuits on the left side board; and a third path passes through the connector between the left side board and the bottom board to power the leakage current sampling (⑯ in the diagram), calibration pulse (⑱ in the diagram), and RS485 communication (⑲ in the diagram) circuits. The 12V power supply in Line 2 also passes directly through the connector between the right side board and the bottom board to power the relay drive circuit (⑰ in the diagram) on the bottom board. When the 220V mains power is interrupted, the system enters a low-power mode, and the backup battery power supply (⑨ in the diagram) passes through the connector between the upper board and the left side board to power the MCU and EEPROM storage circuits on the left side board.

[0022] Signal circuit connection: The MCU (⑤ in the figure) located on the left side panel is the core of the system. First, the MCU's signal line enters the bottom panel through the board connector at the bottom of the left side panel and the bottom panel. It communicates with the metering chip (㉒ in the figure) through the digital isolation chip (⑳ in the figure). The metering chip can obtain the real-time power of the meter through the voltage sampling circuit (㉓ in the figure) and the current sampling circuit (㉔ in the figure). The power data can be obtained by integrating the power over time. The MCU performs fee control based on the power and the current price. The metering chip can also obtain the real-time waveform data of voltage and current through the sampling circuit and upload it to the MCU. The algorithm in the MCU can detect the electrical equipment currently in use based on the waveform data, thereby avoiding some illegal electrical equipment.

[0023] The leakage current sampling circuit (⑯ in the figure) converts the collected real-time leakage current data into a voltage signal, which is then fed into the MCU's ADC sampling port via the connector between the top and left side panels of the base plate. The ADC sampling port calculates the current leakage current based on the collected voltage data. The MCU can control the on / off state of the relay on the top of the base plate (⑯ in the figure) via the board-to-board connector between the left side panel and the top of the base plate, output a calibration pulse signal consistent with the meter constant (⑱ in the figure), and communicate with the outside via RS485 (⑲ in the figure).

[0024] The MCU can detect whether the button (⑥ in the figure) is pressed through the connector between the left side panel and the top panel, control the LED indicator (⑦ in the figure) to be constantly on, constantly off, or flashing, and control the LCD screen (⑧ in the figure) to display relevant data of the meter operation.

[0025] The MCU's signal lines pass through the connector between the left and upper boards, and then through the connector between the upper and right boards to enter the 4G communication module (⑬ in the figure) between the right and right boards for connection, enabling the meter to be connected to our company's IoT platform and have remote monitoring and control functions.

[0026] Preferably, the secondary power conversion circuit of the right side panel includes a flyback power supply module and a DC-DC step-down module. The flyback power supply module converts the voltage output from the 220VAC / DC power supply module into a 12V DC voltage. One 12V DC voltage is converted into a 3.9V DC voltage by the DC-DC step-down module. The 3.9V DC voltage powers the 4G communication module, which is located on the right side panel and connected to the main control chip on the left side panel through copper foil lines. The other 12V DC voltage directly powers the LCD screen, status indicator LEDs, and buttons on the upper panel, as well as the main control chip and storage circuit on the left side panel.

[0027] Preferably, the voltage sampling circuit in the area under the base plate includes a series resistor network. The AC voltage signal is divided by the series resistor network and converted into a weak voltage signal, which is then transmitted to the metering chip. The current sampling circuit includes a manganese copper sheet sampling resistor. The live wire current is converted into a microvolt-level voltage signal by the manganese copper sheet sampling resistor, which is then transmitted to the metering chip.

[0028] Preferably, the relay drive circuit in the area of ​​the base plate is connected to the main control chip on the left side plate through copper foil lines. The main control chip outputs control signals to the relay drive circuit, and the relay drive circuit controls the relay to turn on and off. The calibration pulse output terminal is connected to the main control chip on the left side plate through copper foil lines. The main control chip outputs calibration pulse signals consistent with the meter constant to the calibration pulse output terminal.

[0029] Preferably, the leakage current detection signal input terminal in the area of ​​the base plate is connected to the leakage current sampling circuit, the leakage current sampling circuit is connected to the residual current transformer, the leakage current sampling circuit converts the collected leakage current data into a voltage signal, and the voltage signal is transmitted to the ADC detection port of the main control chip on the left side plate through the copper foil line.

[0030] Preferably, the storage circuit on the left side panel is connected to the main control chip via an I2 bus, and the main control chip stores the processed power data and time data in the storage circuit; the LCD screen on the upper panel is connected to the main control chip via an I2C bus, and the main control chip outputs display data to the LCD screen, which displays the relevant data of the electricity meter operation.

[0031] Preferably, the buttons on the upper panel are connected to the main control chip on the left panel via copper foil circuitry. The main control chip detects whether a button is pressed via an external interrupt. When a button is pressed, the main control chip switches the information displayed on the LCD screen. The status indicator LED is connected to the main control chip via copper foil circuitry, and the main control chip controls the on / off state indicator LED and its blinking.

[0032] Preferably, the PCB layout between the L-shaped high-voltage zone and the low-voltage zone meets the preset electrical clearance and creepage distance, with the electrical clearance not less than 3mm and the creepage distance not less than 4mm; the 220VAC / DC power module on the right side panel adopts an isolation design with an isolation voltage of not less than 2500VAC.

[0033] like Figure 2 As shown, this L-shaped high-voltage zone is specifically composed of area ③ on the base plate and area ⑤ on the right side plate, and is the concentrated area for all high-voltage, high-current circuits and components. Specifically:

[0034] Area ③ (Baseboard High Voltage Area): Primarily houses the power input interface and rectifier bridge circuit. High voltage (220V AC) is supplied through this area, rectified, and then supplied to the right-side board via the inter-board connector.

[0035] Area ③ (Base plate low voltage area): mainly exchanges information with the outside world through pulse terminals, leakage current detection terminals, and RS485 communication terminals.

[0036] Area ⑤ (Right Side Panel High Voltage Area): Primarily houses flyback switching power supply modules, responsible for AC-DC conversion and generating multiple isolated 12V DC power supplies. This area is the core of power conversion and also the main source of electromagnetic interference (EMI).

[0037] This design ensures that all high-voltage, high-current paths are confined within the L-shaped corridor, minimizing routing distance, effectively reducing loop area, and suppressing electromagnetic radiation.

[0038] The L-shaped high-voltage partition maintains sufficient electrical clearance (spatial distance) and creepage distance (surface distance) between itself and other low-voltage areas on the board in the PCB layout. The power module itself adopts an isolation design and transmits signals through a digital isolation chip, forming a double isolation of electrical and physical isolation, completely eliminating interference and safety hazards of high voltage to low-voltage systems.

[0039] Preferably, the RS485 communication terminal in the area of ​​the base plate is connected to the RS485 conversion circuit. The RS485 conversion circuit is connected to the serial port of the main control chip on the left side plate through copper foil lines. The main control chip interacts with external devices through the RS485 conversion circuit and the RS485 communication terminal.

[0040] Preferably, the left side panel is also equipped with an RTC clock circuit. The RTC clock circuit is connected to the main control chip through copper foil lines. The RTC clock circuit provides a time signal to the main control chip, and the main control chip selects the corresponding rate to process the power data according to the time signal.

[0041] like Figure 3 As shown, the device consists of circuits including an MCU, RTC, metering, display, communication, storage, relays, buttons, battery, and leakage detection. Under the control of the MCU, various real-time parameters of the power grid operation are accurately acquired through the sampling circuit, and the time is accurately obtained according to the RTC clock to select the appropriate tariff for data processing. The results are stored in the data memory, and some data is displayed to the outside world through the LCD screen. LEDs indicate the power operation status, buttons switch the information displayed on the LCD screen, and relays control the opening and closing of the meter. It also provides information and data exchange with external interfaces at any time through the communication circuit.

[0042] It integrates metering, fee control, monitoring, alarm, display, remote communication, recharge, control, and management functions to realize the user's electricity metering and electricity information collection and storage. It also supports non-intrusive load identification (arc detection, malicious load detection, voltage regulator detection, air conditioner identification, electric vehicle charging identification) and safe electricity use (overvoltage detection, overcurrent detection, overload detection, leakage detection) and other functions.

[0043] The power supply provides electrical support to the entire system, ensuring that each module functions properly.

[0044] Button circuit: connected to the I / O port of the microcontroller, the MCU detects whether the button is pressed through an external interrupt.

[0045] Analog signal conversion circuit: The leakage current sampling circuit is connected to an external residual current transformer, and internally it is connected to the ADC detection port of the MCU through a current sampling circuit. The current leakage current is collected through the ADC detection port value.

[0046] Metering Sampling Circuit: Metering sampling is divided into voltage sampling and current sampling. The AC voltage signal is divided by a series resistor network, converting the strong voltage signal into a proportionally weak voltage signal. The live wire current is converted into a microvolt-level voltage signal proportional to the current through the sampling resistor of the manganese copper sheet, which is then used by the metering chip for sampling. The metering chip can integrate the power to obtain the energy data, and can also buffer voltage and current waveform data. The MCU communicates with the metering chip to obtain relevant data. Non-intrusive load identification can be performed through the analysis of voltage and current waveforms using algorithms.

[0047] MCU chip: Receives signals from the input section, processes data, and controls the operation of the entire system.

[0048] Memory: connected with MCU chip through I2 bus.

[0049] Display: including LED light and LCD screen, LED and backlight connected with IO port of MCU, LCD screen connected with MCU through I2C bus.

[0050] Relay: IO port of MCU controls opening and closing of relay through driving chip.

[0051] RS485 communication: serial port of MCU connected with RS485 conversion circuit for RS485 communication.

[0052] 4G communication: serial port of MCU connected with serial port of 4G module for 4G communication.

[0053] A connecting device for an electric energy meter circuit board adopts an integrated PCB structure, directly realizes electrical connection of a left side plate, an upper plate, a right side plate and a bottom plate through copper foil lines, omits traditional inter-board connectors, not only greatly reduces the overall volume of the device and simplifies the assembly process, but also fundamentally avoids power supply interruption or data transmission abnormality problems caused by poor connector contact, solves the defect of poor stability of the multi-board splicing structure. At the same time, an L-shaped strong current partition is designed, the power module of the right side plate and the strong current modules such as metering and sampling circuits in the lower area of the bottom plate are arranged in a concentrated manner, and the predetermined electrical clearance and creepage distance requirements are strictly followed, the effective isolation of strong current and weak current areas is realized, the problem of strong current signal interfering with weak current signal and affecting the metering accuracy caused by the dispersion of traditional circuit layout is completely solved, and the operation stability of the device is greatly improved.

[0054] In terms of function and power supply adaptability, the device is also outstanding, and can overcome the power supply and function defects in the background art. The secondary power conversion circuit can convert the output voltage of the power module into multiple adaptive voltages according to the power consumption requirements of different modules, meet the differentiated power supply requirements of different modules such as LCD screen, main control chip and communication module, avoid the situation that the traditional single power output is difficult to adapt to multiple modules and is prone to unstable power supply. In addition, the device integrates leakage detection and remote communication expansion functions, and is connected in order with the main control chip through the copper foil lines, which not only meets the multi-scene monitoring requirements of smart grids, but also ensures efficient and stable data transmission; the addition of the digital isolation chip further guarantees the signal transmission accuracy between the strong current and weak current areas, fully makes up for the shortcomings of the traditional device in single function and signal transmission easily disturbed, and improves the overall performance of the electric energy meter.

[0055] In the description of the utility model, it is necessary to explain, unless another explicit provision and limitation, term "arrange", "install", "link", "connect", "fix" should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or integrally connected;Can be mechanical connection, also can be electrical connection;Can be directly connected, also can be indirectly connected through the intermediate medium, can be two elements inside the communication。For ordinary skilled person in the art, the above-mentioned terms can be understood by the specific meaning in the utility model through specific circumstances.

[0056] Although the embodiments of the utility model have been shown and described, it can be understood by those skilled in the art that various equivalent changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalent scope.

Claims

1. A connection device for a circuit board of an electricity meter, characterized in that, The system includes an integrated PCB structure and an L-shaped high-voltage partition. The integrated PCB structure comprises a left side board, a top board, a right side board, and a bottom board. The left side board houses the main control chip and its core peripheral circuitry. The top board houses the LCD screen, status indicator LEDs, and buttons. The right side board houses the 220VAC / DC power module and secondary power conversion circuitry. The lower area of ​​the bottom board houses the metering chip, voltage sampling circuit, and current sampling circuitry. The upper area of ​​the bottom board houses the low-voltage signal connection devices for external connections. The left side board, top board, right side board, and bottom board are electrically connected as a whole via copper foil traces on the PCB, eliminating the need for inter-board connectors. The L-shaped high-voltage partition is formed by the right side board and the lower area of ​​the bottom board. The 220VAC / DC power module and secondary power conversion circuitry on the right side board, and the metering chip, voltage sampling circuit, and current sampling circuitry on the lower area of ​​the bottom board are all located within the... Within the L-shaped high-voltage zone, the high-voltage connection devices are located at the edge of the L-shaped high-voltage zone. The low-voltage signal connection devices include RS485 communication terminals, calibration pulse output terminals, and leakage current detection signal input terminals, and are centrally arranged on the base plate area. A digital isolation chip is installed between the left side plate and the area below the base plate. The main control chip of the left side plate transmits signals to the metering chip in the area below the base plate through the digital isolation chip. The output terminal of the 220VAC / DC power module of the right side plate is connected via copper foil lines to the LCD screen, status indicator LEDs, and buttons on the upper plate, the main control chip and storage circuit on the left side plate, the low-voltage signal connection devices and relay drive circuit on the area above the base plate, and the metering chip and digital isolation chip in the area below the base plate. The backup battery is connected to the upper plate, and the upper plate is connected to the main control chip and storage circuit on the left side plate via copper foil lines.

2. The connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The secondary power conversion circuit on the right side panel includes a flyback power module and a DC-DC step-down module. The flyback power module converts the voltage output from the 220VAC / DC power module into a 12V DC voltage. One 12V DC voltage is converted into a 3.9V DC voltage by the DC-DC step-down module. The 3.9V DC voltage powers the 4G communication module, which is located on the right side panel and connected to the main control chip on the left side panel via copper foil lines. The other 12V DC voltage directly powers the LCD screen, status indicator LEDs, and buttons on the upper panel, as well as the main control chip and storage circuit on the left side panel.

3. The connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The voltage sampling circuit in the area under the base plate includes a series resistor network. The AC voltage signal is divided by the series resistor network and converted into a weak voltage signal, which is then transmitted to the metering chip. The current sampling circuit includes a manganese copper sheet sampling resistor. The live wire current is converted into a microvolt-level voltage signal by the manganese copper sheet sampling resistor, which is then transmitted to the metering chip.

4. A connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The relay drive circuit on the base plate is connected to the main control chip on the left side plate via copper foil lines. The main control chip outputs control signals to the relay drive circuit, which controls the relay to turn on and off. The calibration pulse output terminal is connected to the main control chip on the left side plate via copper foil lines. The main control chip outputs calibration pulse signals that are consistent with the meter constant to the calibration pulse output terminal.

5. A connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The leakage current detection signal input terminal on the base plate is connected to the leakage current sampling circuit. The leakage current sampling circuit is connected to an external residual current transformer. The leakage current sampling circuit converts the collected leakage current data into a voltage signal. The voltage signal is transmitted to the ADC detection port of the main control chip on the left side plate through the copper foil line.

6. A connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The storage circuit on the left side panel is connected to the main control chip via an I2 bus. The main control chip stores the processed power data and time data in the storage circuit. The LCD screen on the upper panel is connected to the main control chip via an I2C bus. The main control chip outputs display data to the LCD screen, which displays the relevant data of the electricity meter operation.

7. A connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The buttons on the top board are connected to the main control chip on the left side board via copper foil circuitry. The main control chip detects whether a button is pressed via an external interrupt. When a button is pressed, the main control chip switches the information displayed on the LCD screen. The status indicator LEDs are connected to the main control chip via copper foil circuitry, and the main control chip controls the on / off state of the status indicator LEDs and their blinking.

8. A connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The PCB layout between the L-shaped high-voltage and low-voltage zones meets the preset electrical clearances and creepage distances, with electrical clearances not less than 3mm and creepage distances not less than 4mm; the 220VAC / DC power module on the right side panel adopts an isolation design with an isolation voltage of not less than 2500VAC.

9. A connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The RS485 communication terminal on the base plate is connected to the RS485 conversion circuit. The RS485 conversion circuit is connected to the serial port of the main control chip on the left side plate through copper foil lines. The main control chip interacts with external devices through the RS485 conversion circuit and the RS485 communication terminal.

10. A connection device for a circuit board of an electricity meter according to claim 1, characterized in that, The left side panel also houses an RTC clock circuit, which is connected to the main control chip via copper foil lines. The RTC clock circuit provides a time signal to the main control chip, and the main control chip selects the appropriate rate to process the power data based on the time signal.

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