A special intelligent terminal box for high-cold area power grid metering

Abstract

The application discloses a special intelligent terminal box for power grid metering in an alpine region, and relates to the technical field of power metering equipment. The terminal box body is internally provided with an anti-freezing magnetic attraction anti-wrong wiring module, an ultralow-temperature monitoring module, a wide-temperature display module, an alpine control module, a self-temperature-control micro-heat-tracing module, an RFID low-temperature automatic identification module and a hierarchical alarm module. The working temperature range of the terminal box body is -60 DEG C to 120 DEG C, and the terminal box is suitable for the working condition of power grid metering in the northeast alpine region. The application is specially designed for alpine power grid metering, is resistant to extreme cold, prevents wrong wiring, is intelligent in anti-freezing, high in precision in monitoring and automatic in configuration, solves the problems of low-temperature brittle fracture, wrong wiring and icing failure, is suitable for thick glove operation, is prominent in protection and intelligence, is stable and reliable, has a long service life and greatly improves the safety and operation and maintenance efficiency of power grid metering in the alpine region.

Description

Technical Field

[0001] This invention relates to the field of power metering equipment technology, and in particular to a smart terminal box specifically designed for power grid metering in high-altitude and cold regions. Background Technology

[0002] In power metering systems in the frigid Northeast region, terminal boxes are core components that connect metering devices to secondary circuits and withstand wind, snow, and ice. Their extreme cold adaptability directly affects metering accuracy and power grid safety. Conventional terminal blocks and ordinary terminal boxes are only suitable for normal temperature conditions and have many defects in extremely cold environments of -40℃ to -60℃: the outer shell is easily cracked, conductive and magnetic components fail at low temperatures, leading to poor contact and signal distortion; there is no anti-freezing and anti-condensation design, allowing ice and snow to seep in, causing short circuits and metering drift; thick gloves make operation inconvenient, resulting in low wiring efficiency and a high rate of incorrect wiring; there is a lack of low-temperature monitoring and intelligent early warning, making fault prediction difficult and maintenance costs high; and there is no automatic identification and extreme cold-specific protection, resulting in short equipment lifespan and significant safety hazards, failing to meet the metering and maintenance needs of high-altitude power grids.

[0003] To address this, we have proposed a smart terminal box specifically designed for power grid metering in high-altitude and cold regions. Summary of the Invention

[0004] The present invention proposes a smart terminal box for power grid metering in high-altitude and cold regions, which solves the above-mentioned shortcomings of the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A smart terminal box for power grid metering in high-altitude and cold regions includes a terminal box body and an extreme cold protection structure that snaps into the terminal box body. The terminal box body includes an anti-freezing magnetic anti-miswiring module, an ultra-low temperature monitoring module, a wide temperature display module, a high-altitude and cold control module, a self-regulating temperature micro-heating module, an RFID low-temperature automatic identification module, and a graded alarm module.

[0007] The terminal box body operates within a temperature range of -60℃ to 120℃, making it suitable for power grid metering conditions in the extremely cold Northeast region. It features a customized sealed carrier for these conditions, employing a wide-temperature, brittle-resistant modular design that perfectly adapts to anti-freeze magnetic structures and snow / wind protection requirements. Key parameters are as follows:

[0008] 1) Material Selection: The outer shell is made of low-temperature modified PA66+GF30+cold-resistant silicone rubber composite material, with a glass transition temperature ≤-70℃, low-temperature impact strength ≥25kJ / m², and no brittleness or deformation at -60℃. The internal conductive parts are made of H62 brass with a 5μm silver plating and low-temperature passivation treatment, with a contact resistance ≤3mΩ and contact stability meeting the standard at -60℃. The sealing parts are made of VMQ silicone rubber with a brittle temperature ≤-65℃ and a sealing life ≥15 years. The top of the outer shell is integrally set with a 30° snow drainage slope to prevent snow accumulation and icing. The terminal box body has an IP67 protection rating, salt spray resistance ≥600 hours, and a service life of 15 years.

[0009] 2) Structural design: Fully sealed box structure with 12 built-in terminals (8mm spacing, widened spacing to accommodate thick gloves). The terminals are neatly arranged in three-phase (A, B, C) + neutral sections. The top has a 30° snow-guiding slope to quickly slide off snow and prevent accumulation. The terminals use a double fastening method of spring crimping and magnetic attraction. It is compatible with 0.5~6mm² single / multi-strand copper wires. Thick gloves can be used to complete the operation with one hand.

[0010] 3) Rated parameters: Rated voltage AC660V, rated current 63A, insulation resistance >1500MΩ (500VDC) under -60℃ operating conditions, dielectric loss <0.001 (1MHz);

[0011] 4) Installation and compatibility: Supports 35mm DIN rail installation, equipped with a thickened anti-freeze mounting base, overall weight <350g, external dimensions 140mm×90mm×50mm (length×width×height), suitable for various installation scenarios such as high-altitude and cold-weather substations and outdoor metering boxes;

[0012] The ultra-low temperature monitoring module integrates an ultra-low temperature current and voltage monitoring unit, a low temperature connection status monitoring unit, a low temperature condensation monitoring unit, and a miswiring detection unit;

[0013] The cryogenic current and voltage monitoring unit includes:

[0014] Current sensor: A wide-temperature closed-loop Hall effect sensor is selected, with a measurement range of 0~100A (AC), accuracy of ±0.1%FS (-60℃~60℃), linearity <0.05%, response time <10μs, and no zero drift at -60℃.

[0015] Voltage sensor: A wide-temperature voltage divider type sensor is selected, with a measurement range of 0~600V (AC), an accuracy of ±0.1%FS (-60℃~60℃), an input impedance of >10MΩ, and a response time of <5μs;

[0016] Signal processing: Built-in 16-bit wide-temperature ADC (sampling rate 10kHz), stable and reliable data conversion at -60℃, data is transmitted to the control module via SPI interface, with a data update rate of 100Hz;

[0017] The low-temperature connection status monitoring unit includes:

[0018] Contact sensor: A wide temperature and pressure sensitive resistive sensor is selected, with a detection range of 0~10N, sensitivity of 0.5N, accurate detection at -60℃ without error, and a contact pressure of <5N is immediately judged as a loose terminal;

[0019] Temperature sensor: A wide-temperature digital sensor is selected, with a measurement range of -60℃ to 125℃ and an accuracy of ±0.5℃ in the range of -40℃ to 85℃. The sampling frequency is 1Hz, and it monitors the ambient temperature inside the box and the operating temperature of the terminals in real time.

[0020] Condensation sensor: A high-altitude cold-weather-specific sensor is selected to monitor the condensation status inside the box in real time. When the humidity is >95% and the temperature is <0℃, an icing warning is triggered immediately. The signal line uses cold-resistant shielded twisted pair cable to effectively resist electromagnetic interference in high-altitude cold environments.

[0021] The low-temperature condensation monitoring unit and the faulty wiring detection unit include:

[0022] Anomaly detection: Covers all types of faults including short circuit, open circuit, terminal freezing, condensation and icing, poor contact, etc., with a low temperature response delay of ≤50ms;

[0023] Miswiring detection: Connects to the phase detection contacts of the anti-freeze magnetic anti-miswiring module, and combines current and voltage phase data for dual verification to accurately identify miswiring types such as reversed phase lines and reversed polarity. The identification accuracy is ≥99.8%, the response time is ≤20ms, and there are no missed or false alarms in an environment of -60℃.

[0024] The extreme cold protection structure includes a snow-guiding slope, a low-temperature resistant and brittle-resistant outer shell, a thick glove-proof anti-accidental-touch latch, and a wide-temperature lightning protection circuit. The specific functions of the extreme cold protection structure are as follows:

[0025] Prevents snow accumulation and icing: The top of the box has a 30° sloping design to quickly slide off snow and prevent it from piling up. The IP67 fully sealed structure prevents ice, snow and meltwater from seeping into the box.

[0026] Low-temperature flame retardancy: The outer shell has a flame retardancy rating of UL94V0, and its flame retardancy performance does not decrease at -60℃. The self-extinguishing time during vertical burning is <5s, and there is no dripping of molten droplets.

[0027] Corrosion and freeze resistant: conductive parts are silver-plated and passivated, and the outer shell is sprayed with a nano cold-resistant and corrosion-resistant coating. Salt spray resistance is ≥600 hours, and there is no rust or aging in high cold and high humidity environments.

[0028] Lightning and freeze protection: Built-in wide-temperature TSS+TVS surge suppression combination circuit, maximum current capacity of 10kA, stable lightning protection performance at -60℃, and the equipment lightning damage rate is reduced to 0.1 times / 100 units / year;

[0029] Thick gloves prevent accidental contact: Equipped with an enlarged push-button safety lock that requires a special tool to open, with an IP20 protection rating. There is no risk of electric shock when operating with thick gloves.

[0030] The specifications of the high-altitude cold control module are as follows:

[0031] Main chip: The wide-temperature version of STM32F407IGH6 microprocessor is selected, with an operating temperature range of -60℃ to 125℃, a main frequency of 168MHz, and support for floating-point operations. The algorithm operation is smooth and lag-free in extremely cold environments.

[0032] Storage: Equipped with 1MB Flash (program storage), 192KB RAM (data cache), and external 4MB wide-temperature SPI Flash, data storage is stable at -60℃, and can record 6 months of history of extreme cold, freezing, and incorrect wiring.

[0033] Interface: Equipped with a cold-resistant sealed interface, supporting RS485 Modbus RTU communication protocol, it can be connected to the high-altitude power grid operation and maintenance platform to realize remote low-temperature monitoring and historical data retrieval;

[0034] Core algorithms: Built-in high-altitude and extreme cold early warning algorithm, self-temperature control and antifreeze algorithm, and RFID low-temperature identification algorithm, adapting to wide temperature conditions throughout the process, with no low-temperature misjudgment or program lag issues.

[0035] Furthermore, the anti-freeze magnetic anti-miswiring module is specifically developed for the extremely cold conditions of Northeast China, precisely addressing three major pain points: difficulty in wiring with thick gloves, failure of magnetic attraction at low temperatures, and high rate of incorrect wiring. It adopts a four-fold anti-miswiring mechanism of "ultra-low temperature magnetic positioning + phase locking + thick glove foolproofing + anti-freeze contacts," physically eliminating wiring errors in extreme cold and enabling barrier-free operation with cold-proof gloves. The core parameters specifically for high-altitude cold environments are as follows:

[0036] 1) Ultra-low temperature magnetic attraction component: Built-in N40EH ultra-cold resistant sintered NdFeB permanent magnet, magnetic induction intensity 3200±200GS, Curie temperature ≥220℃, working temperature range -60℃~120℃, magnetic force attenuation ≤3% at -60℃, no risk of demagnetization failure, customized differentiated magnetic attraction structure for A, B, C phases and neutral wire (A phase positive magnetic pole convex type, B phase negative magnetic pole concave type, C phase double magnetic pole stepped type, neutral wire no magnetic pole), cold resistant magnetic attraction terminals are pre-installed on the wire connection ends, only the same phase connector can accurately attract and lock, non-corresponding phase cannot be inserted, physical error prevention accuracy reaches 100%, magnetic force attenuation calculation formula is as follows:

[0037] ;

[0038] Constraints: ;

[0039] in, The magnetic attenuation rate;

[0040] Magnetic flux density at room temperature (25℃) (GS);

[0041] The magnetic flux density (GS) is measured at extreme cold (-60℃).

[0042] 2) Thick glove operation adaptation: The magnetic connector is enlarged to a diameter of 12mm, and the surface is treated with anti-slip frosted finish. The insertion and extraction force is strictly controlled at 4-7N. The docking and insertion operations can be completed with one hand using thick gloves. The single-end magnetic docking time is ≤3s, which improves the efficiency by 80% compared with traditional screw wiring.

[0043] The static magnetic attraction force is ≥10N, which can withstand the vibration of the power grid operation in high-altitude and cold regions and the shaking of wind and snow, ensuring the long-term stability of the wiring.

[0044] 3) Anti-freeze contact design: The magnetic mating end face is treated with 2μm silver plating + low temperature anti-freeze coating, the contact resistance at -60℃ is ≤2.5mΩ, eliminating the problem of poor contact at low temperature. It has a built-in 1μm gold-plated cold-resistant phase detection contact with a contact resistance of ≤8mΩ. It is sensitive in the environment of -60℃, the transmission delay of the faulty wiring trigger signal is ≤1ms, and the response time of faulty wiring is ≤20ms.

[0045] 4) Mistake-proof protection design: The box surface is engraved with large-font phase markings and is equipped with color-coded cold-resistant insulating sleeves (A phase yellow, B phase green, C phase red, N phase blue). The phase can be quickly identified even when operating with thick gloves or in snowy weather. The magnetic connector has a built-in anti-freeze insulating baffle and the accidental contact protection level reaches IP20, effectively avoiding the risk of electric shock from accidental contact with live terminals while wearing thick gloves.

[0046] Furthermore, the self-regulating temperature micro-heating module is specifically designed to address the issues of condensation, icing, and terminal freezing in the extremely cold environment of Northeast China. It adopts a low-power self-regulating temperature operation mode, which does not interfere with measurement accuracy. Its core parameters are as follows:

[0047] 1) Temperature control logic: Built-in wide-temperature sensor monitors the temperature inside the box in real time. The micro heating function is automatically activated when the temperature is below -30℃ and automatically shuts off when the temperature rises to -10℃. No manual intervention is required throughout the process.

[0048] 2) Hardware parameters: It adopts a self-regulating electric heating tape, the total power is ≤2W, supports DC8~36V wide voltage input, has no start-up delay in -60℃ environment, and provides uniform heating without local overheating.

[0049] 3) Protection and adaptation: The heat tracing component is fully sealed and antifreeze treated, physically isolated from the monitoring module, does not interfere with the transmission of metering signals, has excellent low temperature resistance and anti-freeze corrosion performance, and its service life is synchronized with that of the terminal box body.

[0050] Furthermore, the specific steps of the RFID low-temperature automatic identification module are as follows:

[0051] Step 1: Low-temperature RFID tag pre-writing: Wide-temperature RFID tags are built into the wiring terminals of metering devices such as smart meters and transformers. They are stable at -60℃. Before leaving the factory, core parameters such as equipment model, transformation ratio, and rated range are written into them.

[0052] Step 2, Magnetic Wiring Trigger Identification: After the terminal box is powered on and the magnetic wiring is completed, the wide-temperature RFID reader will automatically start, with a working frequency of 13.56MHz and a communication distance of 0~5cm, covering the entire terminal area.

[0053] Step 3, Low-Temperature Data Interaction: The card reader emits an radio frequency signal to activate the tag, and the tag transmits device information in reverse. The single interaction time is ≤100ms, and the recognition accuracy is 100% at -60℃.

[0054] Step 4, Automatic Parameter Configuration: After the control module parses the data, it quickly matches the built-in parameter library and automatically completes the configuration of parameters such as metering range and alarm threshold. The entire process takes ≤10 seconds and has a configuration error rate of 0.

[0055] Step 5, Identification Result Feedback: After the parameters are configured, the display screen shows the device information and configuration parameters. If the identification fails, a low-frequency alarm is triggered to remind the maintenance personnel to check.

[0056] Furthermore, the specifications of the wide-temperature display module are as follows:

[0057] Type: It adopts a 2.8-inch wide-temperature TFT LCD screen with an operating temperature range of -60℃ to 80℃, a resolution of 320×240, and a brightness of 400cd / m², which is clearly visible in cold and bright environments.

[0058] Display content: Large font displays core data such as current, voltage, terminal temperature, box temperature, wiring status, anti-freeze mode, and warning information. It can be read quickly even with thick gloves and in snowy weather.

[0059] Interaction design: Equipped with enlarged physical buttons with a diameter of 15mm, which can be easily pressed and operated with thick gloves. It supports page switching, warning pop-up display at the top, and button response time <200ms.

[0060] The graded alarm module is adapted to cold, noisy, and snowy outdoor environments. It adopts a graded alarm mode with sound and light, and can be quickly identified even from a distance or with thick gloves. The core parameters are as follows:

[0061] Audible alarm: Uses a wide-temperature buzzer with a sound pressure level that is normal and has no abnormality at -60℃. It has two modes: continuous ringing (severe abnormality) and intermittent ringing (miswiring / mild antifreeze).

[0062] Light alarm: Equipped with large-size high-brightness LED lights (red, yellow, and blue), with a brightness of 3000mcd, visible from a distance in windy and snowy weather, with two frequencies: fast flashing (severe abnormality) and slow flashing (mild warning);

[0063] The alarm logic is as follows:

[0064] Severe faults such as freezing, condensation, ice formation, short circuits, and open circuits trigger high-frequency audible and visual alarms.

[0065] Intermittent audible and visual alarms are triggered by common wiring errors such as phase wire misalignment.

[0066] Mild anomalies such as low temperature trigger a light warning and simultaneously display a fault message in a pop-up window on the display screen.

[0067] Furthermore, the extreme cold warning algorithm adopts a fixed execution process, which is as follows:

[0068] S1. Ultra-low temperature data acquisition: The control module issues fixed timing commands to synchronously acquire current and voltage, terminal temperature, box temperature, condensation status, and magnetic connection signal. The acquisition is stable and distortion-free at -60℃.

[0069] S2, Wide Temperature Filtering and Noise Reduction: To address electromagnetic interference and low temperature drift characteristics in high-altitude and cold regions, a differentiated filtering algorithm is adopted. High-frequency data undergoes a 100ms sliding filter, low-frequency data undergoes a 5-fold weighted filter, and level signals undergo a 2ms edge filter. The signal-to-noise ratio of the filtered data is ≥65dB.

[0070] S3. Extreme Cold Anomaly Judgment: Retrieve solidification warning thresholds to accurately distinguish fault types such as low temperature freezing, condensation and icing, short circuit, open circuit, incorrect wiring, and poor contact. The judgment logic is unique and unambiguous.

[0071] S4. Graded delay anti-shake: 50ms delay for verification of severe abnormalities (short circuit, freezing), 100ms delay for verification of general abnormalities (high temperature), and 20ms delay for verification of routine miswiring, completely avoiding false alarms caused by instantaneous interference.

[0072] S5. Anti-freeze linkage control: When the temperature inside the box is too low, micro heating will be automatically activated. Condensation, ice formation, and abnormal faults will trigger graded alarms, and the early warning information will be uploaded to the remote operation and maintenance platform simultaneously.

[0073] S6. Data storage and reset: The early warning data is permanently stored in the external Flash memory. It will not be lost when the power is off. After the fault is cleared and the temperature rises to the standard, the system will automatically reset and return to the normal monitoring mode, forming a complete closed loop. The algorithm runs without error and without lag in an extremely cold environment of -60℃.

[0074] Furthermore, the gold plating layer on the surface of the cold-resistant gold-plated phase contact (303) is ≥3μm thick, the gold plating layer does not peel off or oxidize in an environment of -60℃, and the contact resistance of the contact is ≤5mΩ, ensuring the stability of electrical connection in a low-temperature environment.

[0075] Furthermore, the self-regulating micro-heat tracing module has a heat tracing power of 1.5W to 3W, a heat tracing temperature uniformity error of ≤±2℃, and the heat tracing area covers all electrical connection points and monitoring units, eliminating the risk of localized low-temperature icing. The formula for calculating the heat tracing temperature uniformity error is as follows:

[0076] ;

[0077] Constraints: ;

[0078] in, This is to account for the error in the uniformity of the heating temperature.

[0079] The highest measured temperature (°C) in the heated area;

[0080] The lowest measured temperature (°C) in the heated area.

[0081] Furthermore, the wide-temperature surge protection circuit adopts a combination structure of wide-temperature varistor and gas discharge tube, achieving a surge protection level of Class II. It can absorb 10 / 350μs waveform and 25kA surge current, protecting the internal modules from damage caused by lightning surges.

[0082] Furthermore, the thick glove anti-accidental touch lock adopts a press-and-rotate structure, with a lock opening force of 15N to 25N. After the lock is closed, the sealing pressure is uniform, maintaining IP67 sealing performance and preventing the box from being accidentally opened when operating with thick gloves.

[0083] Compared with existing technologies, the beneficial effects of this invention are:

[0084] 1. The working temperature range of this invention is -60℃ to 120℃. The outer shell is made of low-temperature modified composite material, which is not brittle or deformed at -60℃. Combined with a 30° snow accumulation guide slope and IP67 sealing, it prevents snow accumulation and ice from freezing and ice and snow from penetrating, making it suitable for extremely cold outdoor working conditions in Northeast China.

[0085] 2. This invention uses an anti-freeze magnetic anti-misconnection wiring module equipped with an ultra-low temperature permanent magnet, allowing for quick one-handed connection with thick gloves. The differentiated magnetic structure of the three-phase neutral wire achieves physical error prevention, improving wiring accuracy and significantly enhancing wiring efficiency and safety in extremely cold environments.

[0086] 3. This invention eliminates the risk of frozen contacts by automatically starting and stopping the self-controlled temperature micro-heating module at low temperatures; the ultra-low temperature monitoring module has an accuracy of ±0.1%FS, and the condensation and icing early warning accuracy rate exceeds 99.8%. Combined with graded audible and visual alarms, faults can be quickly identified.

[0087] 4. This invention automatically configures equipment parameters within 10 seconds using an RFID module, with zero errors. It features wide-temperature protection, lightning protection, and salt spray resistance, ensuring a service life of up to 15 years and reducing the maintenance costs and equipment replacement frequency of power grids in cold regions.

[0088] In summary, this equipment is specifically designed for metering in high-altitude and cold-weather power grids. It is resistant to extreme cold, prevents incorrect wiring, features intelligent antifreeze, high-precision monitoring, and automatic configuration. It solves problems such as low-temperature brittleness, easy wiring errors, and icing failures. It is suitable for operation with thick gloves, has outstanding protection and intelligence, is stable and reliable, and has a long service life, which greatly improves the safety of metering and operation and maintenance efficiency of power grids in extremely cold regions. Attached Figure Description

[0089] Figure 1 This is a top-view three-dimensional structural diagram of a smart terminal box for power grid metering in high-altitude and cold regions proposed in this invention;

[0090] Figure 2 This is a three-dimensional top-view diagram of the overall structure of a smart terminal box for power grid metering in high-altitude and cold regions proposed in this invention.

[0091] Figure 3 This is a top-view three-dimensional structural diagram of the internal structure of a smart terminal box for power grid metering in high-altitude and cold regions, as proposed in this invention.

[0092] Figure 4 This is a bottom-view three-dimensional structural diagram of the internal structure of a smart terminal box for power grid metering in high-altitude and cold regions, as proposed in this invention.

[0093] Figure 5 This invention presents a block diagram showing the connection between the high-altitude cold region control module and various wide-temperature modules in a smart terminal box for power grid metering in high-altitude cold regions.

[0094] Figure 6 This is a flowchart of an algorithm for early warning and self-temperature control antifreeze of a special intelligent terminal box for power grid metering in high-altitude and cold regions, as proposed in this invention.

[0095] Figure 7 This is a schematic diagram of the anti-freezing magnetic anti-miswiring module structure of a smart terminal box for power grid metering in high-altitude and cold regions proposed in this invention;

[0096] Figure 8 This invention presents a flowchart of the RFID low-temperature automatic identification interaction process for a smart terminal box specifically designed for power grid metering in cold regions.

[0097] In the diagram: 1. Terminal box body; 2. Extreme cold protection structure; 3. Anti-freeze magnetic anti-miswiring module; 4. Ultra-low temperature monitoring module; 5. Wide temperature display module; 6. High cold control module; 7. Self-regulating micro-heating module; 8. Thick glove anti-accidental touch lock; 9. RFID low temperature automatic identification module; 10. Graded alarm module. Detailed Implementation

[0098] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0099] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0100] Example 1

[0101] Reference Figure 1-8 A smart terminal box for power grid metering in high-altitude and cold regions includes a terminal box body 1 and an extreme cold protection structure 2 that snaps into the terminal box body 1. The terminal box body 1 includes an anti-freezing magnetic anti-miswiring module 3, an ultra-low temperature monitoring module 4, a wide temperature display module 5, a high-altitude and cold control module 6, a self-temperature controlled micro-heating module 7, an RFID low-temperature automatic identification module 9, and a graded alarm module 10.

[0102] The terminal box body 1 operates within a temperature range of -60℃ to 120℃, making it suitable for power grid metering conditions in the extremely cold Northeast region. It features a customized sealed carrier for these conditions, employing a wide-temperature, brittle-resistant modular design that perfectly adapts to anti-freeze magnetic structures and snow / wind protection requirements. Key parameters are as follows:

[0103] 1) Material Selection: The outer shell is made of low-temperature modified PA66+GF30+cold-resistant silicone rubber composite material, with a glass transition temperature ≤-70℃, low-temperature impact strength ≥25kJ / m², and no brittleness or deformation at -60℃. The internal conductive parts are made of H62 brass with a 5μm silver plating and low-temperature passivation treatment, with a contact resistance ≤3mΩ and contact stability meeting the standard at -60℃. The sealing parts are made of VMQ silicone rubber with a brittle temperature ≤-65℃ and a sealing life ≥15 years. The top of the outer shell is integrated with a 30° snow-draining slope to prevent snow accumulation and icing. The terminal box body has an IP67 protection rating, salt spray resistance ≥600 hours, and a service life of 15 years.

[0104] 2) Structural design: Fully sealed box structure with 12 built-in terminals (8mm spacing, widened spacing to accommodate thick gloves). The terminals are neatly arranged in three-phase (A, B, C) + neutral sections. The top has a 30° snow-guiding slope to quickly slide off snow and prevent accumulation. The terminals use a double fastening method of spring crimping and magnetic attraction. It is compatible with 0.5~6mm² single / multi-strand copper wires. Thick gloves can be used to complete the operation with one hand.

[0105] 3) Rated parameters: Rated voltage AC660V, rated current 63A, insulation resistance >1500MΩ (500VDC) under -60℃ operating conditions, dielectric loss <0.001 (1MHz);

[0106] 4) Installation and compatibility: Supports 35mm DIN rail installation, equipped with a thickened anti-freeze mounting base, overall weight <350g, external dimensions 140mm×90mm×50mm (length×width×height), suitable for various installation scenarios such as high-altitude and cold-weather substations and outdoor metering boxes;

[0107] The ultra-low temperature monitoring module 4 integrates an ultra-low temperature current and voltage monitoring unit, a low temperature connection status monitoring unit, a low temperature condensation monitoring unit, and a miswiring detection unit;

[0108] The cryogenic current and voltage monitoring unit includes:

[0109] Current sensor: A wide-temperature closed-loop Hall effect sensor is selected, with a measurement range of 0~100A (AC), accuracy of ±0.1%FS (-60℃~60℃), linearity <0.05%, response time <10μs, and no zero drift at -60℃.

[0110] Voltage sensor: A wide-temperature voltage divider type sensor is selected, with a measurement range of 0~600V (AC), an accuracy of ±0.1%FS (-60℃~60℃), an input impedance of >10MΩ, and a response time of <5μs;

[0111] Signal processing: Built-in 16-bit wide-temperature ADC (sampling rate 10kHz), stable and reliable data conversion at -60℃, data is transmitted to the control module via SPI interface, with a data update rate of 100Hz;

[0112] The low-temperature connection status monitoring unit includes:

[0113] Contact sensor: A wide temperature and pressure sensitive resistive sensor is selected, with a detection range of 0~10N, sensitivity of 0.5N, accurate detection at -60℃ without error, and a contact pressure of <5N is immediately judged as a loose terminal;

[0114] Temperature sensor: A wide-temperature digital sensor is selected, with a measurement range of -60℃ to 125℃ and an accuracy of ±0.5℃ in the range of -40℃ to 85℃. The sampling frequency is 1Hz, and it monitors the ambient temperature inside the box and the operating temperature of the terminals in real time.

[0115] Condensation sensor: A high-altitude cold-weather-specific sensor is selected to monitor the condensation status inside the box in real time. When the humidity is >95% and the temperature is <0℃, an icing warning is triggered immediately. The signal line uses cold-resistant shielded twisted pair cable to effectively resist electromagnetic interference in high-altitude cold environments.

[0116] The low-temperature condensation monitoring unit and the faulty wiring detection unit include:

[0117] Anomaly detection: Covers all types of faults including short circuit, open circuit, terminal freezing, condensation and icing, poor contact, etc., with a low temperature response delay of ≤50ms;

[0118] Miswiring detection: Connects to the anti-freeze magnetic anti-miswiring module with 3 phase detection contacts, combined with dual verification of current and voltage phase data, accurately identifies miswiring types such as reversed phase lines and reversed polarity, with an accuracy rate of ≥99.8%, a response time of ≤20ms, and no missed or false alarms in an environment of -60℃;

[0119] The extreme cold protection structure 2 includes a snow-guiding slope, a low-temperature resistant and brittle outer shell, a thick glove-proof anti-accidental-touch latch 8, and a wide-temperature surge protection circuit. The specific functions of the extreme cold protection structure are as follows:

[0120] Prevents snow accumulation and icing: The top of the box has a 30° sloping design to quickly slide off snow and prevent it from piling up. The IP67 fully sealed structure prevents ice, snow and meltwater from seeping into the box.

[0121] Low-temperature flame retardancy: The outer shell has a flame retardancy rating of UL94V0, and its flame retardancy performance does not decrease at -60℃. The self-extinguishing time during vertical burning is <5s, and there is no dripping of molten droplets.

[0122] Corrosion and freeze resistant: conductive parts are silver-plated and passivated, and the outer shell is sprayed with a nano cold-resistant and corrosion-resistant coating. Salt spray resistance is ≥600 hours, and there is no rust or aging in high cold and high humidity environments.

[0123] Lightning and freeze protection: Built-in wide-temperature TSS+TVS surge suppression combination circuit, maximum current capacity of 10kA, stable lightning protection performance at -60℃, and the equipment lightning damage rate is reduced to 0.1 times / 100 units / year;

[0124] Thick gloves prevent accidental contact: Equipped with an enlarged push-button safety lock that requires a special tool to open, with an IP20 protection rating. There is no risk of electric shock when operating with thick gloves.

[0125] The specifications of the high-altitude cold control module 6 are as follows:

[0126] Main chip: The wide-temperature version of STM32F407IGH6 microprocessor is selected, with an operating temperature range of -60℃ to 125℃, a main frequency of 168MHz, and support for floating-point operations. The algorithm operation is smooth and lag-free in extremely cold environments.

[0127] Storage: Equipped with 1MB Flash (program storage), 192KB RAM (data cache), and external 4MB wide-temperature SPI Flash, data storage is stable at -60℃, and can record 6 months of history of extreme cold, freezing, and incorrect wiring.

[0128] Interface: Equipped with a cold-resistant sealed interface, supporting RS485 Modbus RTU communication protocol, it can be connected to the high-altitude power grid operation and maintenance platform to realize remote low-temperature monitoring and historical data retrieval;

[0129] Core algorithms: Built-in high-altitude and extreme cold early warning algorithm, self-temperature control and antifreeze algorithm, and RFID low-temperature identification algorithm, adapting to wide temperature conditions throughout the process, with no low-temperature misjudgment or program lag issues.

[0130] In this invention, the antifreeze magnetic anti-miswiring module 3 is specially developed for the extremely cold working conditions in Northeast China. It precisely solves three major pain points: difficulty in wiring with thick gloves, failure of magnetic attraction at low temperatures, and high rate of incorrect wiring. It adopts a four-fold anti-miswiring mechanism of "ultra-low temperature magnetic positioning + phase locking + thick gloves to prevent fooling + antifreeze contacts" to physically eliminate wiring errors in extreme cold and enable barrier-free operation with cold-proof gloves. The core parameters specifically for high-altitude cold environments are as follows:

[0131] 1) Ultra-low temperature magnetic attraction component: Built-in N40EH ultra-cold resistant sintered NdFeB permanent magnet 301, magnetic induction intensity 3200±200GS, Curie temperature ≥220℃, working temperature range -60℃~120℃, magnetic force attenuation ≤3% in -60℃ environment, no risk of demagnetization failure; customized differentiated magnetic attraction structures for A, B, C phases and neutral wire (A phase positive magnetic pole convex type, B phase negative magnetic pole concave type, C phase double magnetic pole stepped type, neutral wire no magnetic pole), cold resistant magnetic attraction terminals are pre-installed on the wire connection end, only the same phase connector can be accurately attracted and locked, non-corresponding phase cannot be inserted, physical error prevention accuracy reaches 100%;

[0132] 2) Thick glove operation adaptation: The magnetic connector 302 is enlarged to a diameter of 12mm, and the surface is treated with anti-slip frosted finish. The insertion and extraction force is strictly controlled between 4 and 7N. The docking and insertion operations can be completed with one hand using thick gloves. The single-end magnetic docking time is ≤3s, which improves the efficiency by 80% compared with traditional screw wiring.

[0133] The static magnetic attraction force is ≥10N, which can withstand the vibration of the power grid operation in high-altitude and cold regions and the shaking of wind and snow, ensuring the long-term stability of the wiring.

[0134] 3) Anti-freeze contact design: The magnetic mating end face is treated with 2μm silver plating + low temperature anti-freeze coating, the contact resistance at -60℃ is ≤2.5mΩ, eliminating the problem of poor contact at low temperature. It has a built-in 1μm gold-plated cold-resistant phase detection contact with a contact resistance of ≤8mΩ. It is sensitive in the environment of -60℃, the transmission delay of the faulty wiring trigger signal is ≤1ms, and the response time of faulty wiring is ≤20ms.

[0135] 4) Mistake-proof protection design: The box surface is engraved with large-font phase markings and is equipped with color-coded cold-resistant insulating sleeves (A phase yellow, B phase green, C phase red, N phase blue). The phase can be quickly identified even when operating with thick gloves or in snowy weather. The magnetic connector 302 has a built-in anti-freeze insulating baffle and an IP20 anti-accidental contact rating, effectively avoiding the risk of electric shock from accidentally touching live terminals with thick gloves.

[0136] In this invention, the self-temperature controlled micro-heating module 7 is specifically designed to address the problems of condensation, icing, and terminal freezing in the extremely cold environment of Northeast China. It adopts a low-power self-temperature controlled operation mode, which does not interfere with the metering accuracy. The core parameters are as follows:

[0137] 1) Temperature control logic: Built-in wide-temperature sensor monitors the temperature inside the box in real time. The micro heating function is automatically activated when the temperature is below -30℃ and automatically shuts off when the temperature rises to -10℃. No manual intervention is required throughout the process.

[0138] 2) Hardware parameters: It adopts a self-regulating electric heating tape, the total power is ≤2W, supports DC8~36V wide voltage input, has no start-up delay in -60℃ environment, and provides uniform heating without local overheating.

[0139] 3) Protection and adaptation: The heat tracing component is fully sealed and antifreeze treated, physically isolated from the monitoring module, does not interfere with the transmission of metering signals, has excellent low temperature resistance and anti-freeze corrosion performance, and its service life is synchronized with that of the terminal box body 1.

[0140] In this invention, the specific steps of the RFID low-temperature automatic identification module 9 are as follows:

[0141] Step 1: Low-temperature RFID tag pre-writing: Wide-temperature RFID tags are built into the wiring terminals of metering devices such as smart meters and transformers. They are stable at -60℃. Before leaving the factory, core parameters such as equipment model, transformation ratio, and rated range are written into them.

[0142] Step 2, Magnetic Wiring Trigger Identification: After the terminal box is powered on and the magnetic wiring is completed, the wide-temperature RFID reader will automatically start, with a working frequency of 13.56MHz and a communication distance of 0~5cm, covering the entire terminal area.

[0143] Step 3, Low-Temperature Data Interaction: The card reader emits an radio frequency signal to activate the tag, and the tag transmits device information in reverse. The single interaction time is ≤100ms, and the recognition accuracy is 100% at -60℃.

[0144] Step 4, Automatic Parameter Configuration: After the control module parses the data, it quickly matches the built-in parameter library and automatically completes the configuration of parameters such as metering range and alarm threshold. The entire process takes ≤10 seconds and has a configuration error rate of 0.

[0145] Step 5, Identification Result Feedback: After the parameters are configured, the display screen shows the device information and configuration parameters. If the identification fails, a low-frequency alarm is triggered to remind the maintenance personnel to check.

[0146] In this invention, the specifications of the wide-temperature display module 5 are as follows:

[0147] Type: It adopts a 2.8-inch wide-temperature TFT LCD screen with an operating temperature range of -60℃ to 80℃, a resolution of 320×240, and a brightness of 400cd / m², which is clearly visible in cold and bright environments.

[0148] Display content: Large font displays core data such as current, voltage, terminal temperature, box temperature, wiring status, anti-freeze mode, and warning information. It can be read quickly even with thick gloves and in snowy weather.

[0149] Interaction design: Equipped with enlarged physical buttons with a diameter of 15mm, which can be easily pressed and operated with thick gloves. It supports page switching, warning pop-up display at the top, and button response time <200ms.

[0150] The graded alarm module 10 is suitable for cold, noisy, and snowy outdoor environments. It adopts a graded alarm mode with sound and light, and can be quickly identified even from a distance or with thick gloves. The core parameters are as follows:

[0151] Audible alarm: Uses a wide-temperature buzzer with a sound pressure level that is normal and has no abnormality at -60℃. It has two modes: continuous ringing (severe abnormality) and intermittent ringing (miswiring / mild antifreeze).

[0152] Light alarm: Equipped with large-size high-brightness LED lights (red, yellow, and blue), with a brightness of 3000mcd, visible from a distance in windy and snowy weather, with two frequencies: fast flashing (severe abnormality) and slow flashing (mild warning);

[0153] The alarm logic is as follows:

[0154] Severe faults such as freezing, condensation, ice formation, short circuits, and open circuits trigger high-frequency audible and visual alarms.

[0155] Intermittent audible and visual alarms are triggered by common wiring errors such as phase wire misalignment.

[0156] Mild anomalies such as low temperature trigger a light warning and simultaneously display a fault message in a pop-up window on the display screen.

[0157] In this invention, the extreme cold warning algorithm adopts a fixed execution process, which is as follows:

[0158] S1. Ultra-low temperature data acquisition: The control module issues fixed timing commands to synchronously acquire current and voltage, terminal temperature, box temperature, condensation status, and magnetic connection signal. The acquisition is stable and distortion-free at -60℃.

[0159] S2, Wide Temperature Filtering and Noise Reduction: To address electromagnetic interference and low temperature drift characteristics in high-altitude and cold regions, a differentiated filtering algorithm is adopted. High-frequency data undergoes a 100ms sliding filter, low-frequency data undergoes a 5-fold weighted filter, and level signals undergo a 2ms edge filter. The signal-to-noise ratio of the filtered data is ≥65dB.

[0160] S3. Extreme Cold Anomaly Judgment: Retrieve solidification warning thresholds to accurately distinguish fault types such as low temperature freezing, condensation and icing, short circuit, open circuit, incorrect wiring, and poor contact. The judgment logic is unique and unambiguous.

[0161] S4. Graded delay anti-shake: 50ms delay for verification of severe abnormalities (short circuit, freezing), 100ms delay for verification of general abnormalities (high temperature), and 20ms delay for verification of routine miswiring, completely avoiding false alarms caused by instantaneous interference.

[0162] S5. Anti-freeze linkage control: When the temperature inside the box is too low, micro heating will be automatically activated. Condensation, ice formation, and abnormal faults will trigger graded alarms, and the early warning information will be uploaded to the remote operation and maintenance platform simultaneously.

[0163] S6. Data storage and reset: The early warning data is permanently stored in the external Flash memory. It will not be lost when the power is off. After the fault is cleared and the temperature rises to the standard, the system will automatically reset and return to the normal monitoring mode, forming a complete closed loop. The algorithm runs without error and without lag in an extremely cold environment of -60℃.

[0164] In this invention, the gold plating layer on the surface of the cold-resistant gold-plated phase contact 303 is ≥3μm thick, the gold plating layer does not peel off or oxidize in an environment of -60℃, and the contact resistance of the contact is ≤5mΩ, ensuring the electrical connection stability in a low-temperature environment.

[0165] In this invention, the self-regulating micro-heating module 7 has a heat tracing power of 1.5W to 3W, a heat tracing temperature uniformity error of ≤±2℃, and the heat tracing area covers all electrical connection contact points and monitoring units, eliminating the risk of local low temperature icing.

[0166] In this invention, the wide-temperature surge protection circuit adopts a combination structure of wide-temperature varistor and gas discharge tube, and the surge protection level reaches Class II. It can absorb 10 / 350μs waveform and 25kA surge current, protecting the internal modules from damage caused by lightning surges.

[0167] In this invention, the thick glove anti-accidental contact lock 8 adopts a press-and-rotate structure. The lock opening force is 15N to 25N. After the lock is closed, the sealing pressure is uniform, maintaining IP67 sealing performance and preventing the box from being opened accidentally when operating with thick gloves.

[0168] Working principle:

[0169] (I) Installation in cold regions and anti-freeze wiring:

[0170] 1. Extreme cold installation preparation: Check that the terminal box body 1 is sealed and free from cracks and deformation, confirm that the antifreeze magnetic anti-miswiring module 3 and the self-controlled temperature micro-heating module 7 are functioning normally, complete the -60℃ pre-cooling test, check the phase of the cold-resistant magnetic connector 302 of the wire, and adapt to the requirements of thick gloves for operation.

[0171] 2. Rail fixing: Insert the terminal box body 1 into a 35mm DIN anti-freeze rail and install it in a compliant position that is sheltered from wind and snow, ensuring that the snow drainage slope faces upwards, and tighten it to prevent frost heave and displacement;

[0172] 3. Anti-freeze magnetic connection: Strip the cold-resistant insulation layer of the wire (8-10mm in length), pre-install the corresponding phase magnetic connector 302, use thick gloves to hold the connector with one hand, align it with the phase mark 1 on the box body and magnetically connect it. Only the same phase can be locked. After performing an 8N pull force test and finding no displacement, close the sealing latch to complete the wiring operation.

[0173] (II) Initialization of the high-altitude cold system:

[0174] 1. Connect to a DC24V wide-temperature power supply. The wide-temperature display screen will start up within 3 seconds, and the self-regulating micro-heating module 7 will automatically detect the temperature inside the box.

[0175] 2. The RFID low-temperature module automatically identifies the connected equipment, completes automatic parameter configuration within 10 seconds, and displays the high-altitude and cold-weather operating parameters in real time on the screen;

[0176] 3. The system self-checks the extreme cold, antifreeze, and wiring status. If the status is normal, it enters the real-time monitoring mode; if abnormal, it immediately triggers an audible and visual alarm.

[0177] (III) Real-time monitoring and maintenance of extreme cold weather:

[0178] The ultra-low temperature monitoring module 4 collects full-dimensional data at a fixed frequency, and the high-altitude cold control module 6 links to self-temperature control and early warning algorithms for real-time analysis.

[0179] The wide-temperature display screen refreshes operating data in large font, and thick gloves can access historical records via enlarged buttons;

[0180] If the internal temperature is too low, the heating system will automatically start. Faults such as condensation and icing, or incorrect wiring will immediately trigger a tiered alarm, allowing maintenance personnel to quickly handle the situation through remote monitoring or on-site.

[0181] (iv) Troubleshooting in cold weather:

[0182]

[0183] (V) Daily maintenance in high-altitude and cold regions:

[0184] Clean the box of snow and frost every quarter, and check the sealing performance and micro-heating function.

[0185] The measurement accuracy is calibrated annually using a wide-temperature standard source, and the functions of the magnetic attraction and alarm modules are tested.

[0186] Wear thick gloves throughout the maintenance process and never wash the equipment with water to ensure long-term stable operation of the terminal box under extremely cold conditions.

[0187] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A smart terminal box for power grid metering in high-altitude and cold regions, comprising a terminal box body (1) and an extreme cold protection structure (2) that snaps into the terminal box body (1), characterized in that, The terminal box body (1) includes an antifreeze magnetic anti-miswiring module (3), an ultra-low temperature monitoring module (4), a wide temperature display module (5), a high-altitude cold control module (6), a self-temperature-controlled micro-heating module (7), an RFID low-temperature automatic identification module (9), and a graded alarm module (10). The terminal box body (1) has a working temperature range of -60℃ to 120℃, and is suitable for power grid metering conditions in the extremely cold Northeast region. The ultra-low temperature monitoring module (4) integrates an ultra-low temperature current and voltage monitoring unit, a low temperature connection status monitoring unit, a low temperature condensation monitoring unit, and a miswiring detection unit; The extreme cold protection structure (2) includes a snow-guiding slope, a low-temperature resistant and brittle shell, a thick glove anti-accidental contact lock (8), and a wide-temperature lightning protection circuit; The high-altitude cold control module (6) has a built-in extreme cold early warning algorithm and a self-temperature control and antifreeze algorithm. The high-altitude cold control module (6) is connected to the antifreeze magnetic anti-miswiring module (3) to realize the integrated functions of convenient wiring with thick gloves, alarm for miswiring, and low-temperature antifreeze early warning.

2. The intelligent terminal box for power grid metering in high-altitude and cold regions according to claim 1, characterized in that, The antifreeze magnetic anti-misconnection module (3) has a built-in N40EH type ultra-cold resistant sintered neodymium iron boron permanent magnet (301). The permanent magnet has a magnetic force attenuation of ≤3% in an environment of -60℃ and a static magnetic attraction force of ≥10N. The magnetic connector (302) adopts an enlarged and thickened structure, which is suitable for one-handed operation with thick gloves, and the single-end docking time is ≤3s; The magnetic connector (302) features a differentiated phase magnetic attraction structure for the three phases A, B, and C, as well as the neutral wire, to achieve physical prevention of incorrect wiring and a wiring accuracy rate of 100%. The module is equipped with cold-resistant gold-plated phase contacts (303), and the response time for incorrect wiring is ≤20ms.

3. The intelligent terminal box for power grid metering in high-altitude and cold regions according to claim 1, characterized in that, The self-temperature controlled micro-heating module (7) adopts a low-power self-controlled operation mode. When the ambient temperature inside the box is below -30℃, it automatically starts anti-freeze heating and automatically shuts off when the temperature rises back to -10℃. The outer shell of the terminal box body (1) is made of low-temperature modified PA66+GF30 composite material with a glass transition temperature of ≤-70℃. It is not brittle or deformed in an environment of -60℃. The top of the shell is integrally set with a 30° snow guide slope to prevent snow accumulation and icing.

4. The intelligent terminal box for power grid metering in high-altitude and cold regions according to claim 1, characterized in that, The ultra-low temperature monitoring module (4) has a current and voltage measurement accuracy of ±0.1%FS within the temperature range of -60℃ to 60℃, and the matching temperature sensor has a measurement accuracy of ±0.5℃. The accuracy rate of condensation and icing early warning is >99.8%. The RFID low-temperature automatic identification module (9) completes the automatic configuration of equipment parameters within 10 seconds with a configuration error rate of 0, and is suitable for debugging in extremely cold environments without human intervention.

5. A smart terminal box for power grid metering in high-altitude and cold regions according to claim 1, characterized in that, The wide-temperature display module (5) is equipped with enlarged physical buttons with a diameter of 15mm. The enlarged physical buttons meet the needs of barrier-free operation with thick gloves. The graded alarm module (10) uses a combination of a 90dB wide-temperature buzzer and a high-brightness tri-color LED light, and the alarm signal can be clearly identified in snowy weather and extremely cold environments. The terminal box body (1) has an IP67 protection rating, a salt spray resistance of ≥600 hours, and a service life of 15 years.

6. The intelligent terminal box for power grid metering in high-altitude and cold regions according to claim 1, characterized in that, The extreme cold warning algorithm adopts a fixed execution process, which consists of the following steps: ultra-low temperature multi-source data acquisition, wide temperature filtering and noise reduction processing, joint judgment of extreme cold anomalies, graded delay anti-shake verification, anti-freezing linkage control execution, fixed storage of warning data, and automatic reset after anomaly resolution.

7. A smart terminal box for power grid metering in high-altitude and cold regions according to claim 2, characterized in that, The gold plating layer on the surface of the cold-resistant gold-plated phase contact (303) is ≥3μm thick, and the gold plating layer does not peel off or oxidize in an environment of -60℃. The contact resistance of the contact is ≤5mΩ, ensuring the electrical connection stability in a low-temperature environment.

8. A smart terminal box for power grid metering in high-altitude and cold regions according to claim 1, characterized in that, The self-controlled temperature micro-heating module (7) has a heat tracing power of 1.5W to 3W, a heat tracing temperature uniformity error of ≤±2℃, and the heat tracing area covers all electrical connection points and monitoring units, eliminating the hidden danger of local low temperature icing.

9. A smart terminal box for power grid metering in high-altitude and cold regions according to claim 1, characterized in that, The wide-temperature surge protection circuit adopts a combination structure of wide-temperature varistor and gas discharge tube, and the surge protection level reaches Class II. It can absorb 10 / 350μs waveform and 25kA lightning current, protecting the internal modules from damage caused by lightning surges.

10. A smart terminal box for power grid metering in high-altitude and cold regions according to claim 1, characterized in that, The thick glove anti-accidental touch lock (8) adopts a press-rotate structure. The lock opening force is 15N~25N. After the lock is closed, the sealing pressure is uniform, maintaining IP67 sealing performance and preventing the box from being opened accidentally when the thick gloves are in operation.

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