Multi-loop electric energy meter

Abstract

The utility model provides a multi-loop electric energy meter, which comprises a shell, and a three-phase metering element, three single-phase metering elements, a three-phase relay and three groups of single-phase relays which are arranged in the shell, the three-phase metering element and the three-phase relay are located in a three-phase loop, and the three-phase metering element is connected with the three-phase metering unit and used for transmitting collected three-phase current signals to the three-phase metering unit for metering; the wire outlet end of each single-phase metering element is connected with the corresponding single-phase metering unit, and the electric quantity of each single-phase loop is independently metered. According to the utility model, a three-phase meter and three single-phase meters are integrated into a multi-loop electric energy meter, so that a user scene of'two meters in one household 'and'three meters in one household' is optimized into one meter in one household, differentiated power utilization requirements of users are met, the investment of power grid equipment is reduced, the field installation space is saved, the workload of basic-level operation and maintenance services is reduced, and the working efficiency of the multi-loop electric energy meter is improved. The management complexity is reduced, and the integrated and intelligent upgrading of the metering equipment is realized.

Description

Technical Field

[0001] This utility model belongs to the field of electricity meter technology, and specifically relates to a multi-circuit electricity meter. Background Technology

[0002] Against the backdrop of energy consumption structure transformation and the vigorous promotion of the "coal-to-electricity" project, the electricity demand of urban and rural residents in Xinjiang and other regions has become increasingly diversified and complex. User scenarios such as "one household with two meters" (e.g., "residential + single-phase electric heating" or "residential + three-phase electric heating") and "one household with three meters" (e.g., "residential + electric heating + commercial" or "residential + electric heating + three-phase power") have become the norm.

[0003] To meet these differentiated electricity demands, existing technologies typically employ a "multiple meters per household" configuration, which uses a three-phase meter combined with one or two single-phase meters for metering. The three-phase meter internally consists of a set of three-phase relays and three sets of current transformers, with its input and output terminals located at the bottom of the meter, including three-phase input and output lines (ABCN) and an N-phase output line, as shown in CN201610754132.2. The single-phase meter internally consists of a set of single-phase relays and a set of current transformers, with its input and output terminals also located at the bottom of the meter, divided into single-phase input and output lines for voltage and current, as shown in patent CN201610756010.7.

[0004] However, this "one household, multiple meters" model presents numerous problems in practical applications. First, the configuration of multiple meters multiplies the investment in power grid equipment, significantly increasing the construction cost of the power system. Second, each meter requires independent installation space, leading to space constraints in residential or commercial settings where installation areas are limited, making it difficult to meet reasonable installation layout requirements. Third, the large number of dispersed meters increases the workload of grassroots maintenance personnel, significantly increasing the pressure on maintenance services; whether it's daily inspections, troubleshooting, or equipment replacement, more manpower and time are required. Finally, the independent operation and management of multiple meters greatly increases the complexity of electricity metering data collection, analysis, and management, hindering the efficient operation of the power system. Furthermore, in existing three-phase and single-phase meters, the incoming and outgoing lines are located at the bottom of the meter. This wiring layout makes it easy for operators' hands to come into contact with live parts during on-site operations, posing a safety hazard and failing to fully guarantee the safety of wiring work.

[0005] In response to the problems caused by the "one household, multiple meters" model, such as high equipment investment, limited installation space, heavy operation and maintenance pressure, complex management, and potential wiring safety hazards, it is necessary to design a multi-circuit energy meter that integrates three-phase and single-phase metering functions. Utility Model Content

[0006] To address the technical problems existing in the prior art, this utility model provides a multi-circuit energy meter.

[0007] In this embodiment of the utility model, a multi-circuit energy meter includes a housing, and a three-phase metering element, three single-phase metering elements, a three-phase relay, and three sets of single-phase relays installed in the housing. The housing has an inlet terminal block for connecting an external inlet cable and an outlet terminal block for connecting an external outlet cable. The three-phase metering element and the three-phase relay are located in the three-phase circuit. The three-phase metering element is connected to the three-phase metering unit and is used to transmit the collected three-phase current signal to the three-phase metering unit for metering. The three single-phase metering elements are located in their respective single-phase circuits. Each single-phase metering element has a corresponding single-phase relay in its single-phase circuit. The outlet terminal of each single-phase metering element is connected to the corresponding single-phase metering unit, so that the electricity of each single-phase circuit is independently metered.

[0008] Compared with the prior art, the beneficial effects of the superior technical solution of this utility model include:

[0009] 1. This utility model integrates the core components of a three-phase meter and three single-phase meters (three phase transformers, three single phase transformers, three sets of three-phase relays, and three sets of single-phase relays) into a multi-circuit energy meter, thereby optimizing the user scenario of "one household with two meters" or "one household with three meters" into one household with one meter. This meets the differentiated electricity needs of users, reduces investment in power grid equipment, saves on-site installation space, reduces the workload of grassroots operation and maintenance services, reduces management complexity, and realizes the integration and intelligent upgrading of metering equipment.

[0010] 2. The left-right arrangement of the three-phase relay and single-phase relay in this utility model, as well as the specific layout and spacing of the incoming and outgoing lines, make the internal current path of the meter the shortest, the impedance the lowest, the voltage drop on the copper busbar the smallest, and the overall heat generation reduced, while ensuring the accuracy of the measurement.

[0011] 3. This utility model, through reasonable electrical clearance design and the setting of isolation barriers, makes the electrical design more reasonable, the on-site wiring safer, reduces safety hazards, and limits the spacing between single and three phases inside the meter, reducing the mutual influence between them and ensuring the reliability of relay tripping and closing.

[0012] 4. The outer shell of this utility model is made of high weather-resistant PC+(10±2)% GF material, the inlet terminal block and outlet terminal block are made of high weather-resistant PBT+(30±2)% GF material, and the sealing strip is dustproof and waterproof, so that the electricity meter can work reliably for a long time in the temperature range of -40℃~70℃, making it able to adapt to different regional climate conditions. Whether in the cold winter in the north or the hot summer in the south, the electricity meter can operate normally and meet the requirements of harsh climate conditions such as high and low temperature tests and double 85 tests, thus expanding the application range of the electricity meter. There is no need to design or select different types of electricity meters according to the climate characteristics of different regions. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the internal structure of a multi-loop power meter with three-phase and single-phase metering functions, as shown in the embodiment.

[0014] Figure 2 This is a wiring diagram of a multi-circuit power meter in an embodiment.

[0015] The reference numerals in the accompanying drawings include: housing 1, three-phase metering element (three-phase transformer) 2, single-phase metering element (single-phase transformer) 3, three-phase relay 4, single-phase relay 5, incoming terminal block 6, outgoing terminal block 7. Detailed Implementation

[0016] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0017] This embodiment provides a multi-circuit energy meter, such as Figure 1 As shown, in a preferred embodiment, the multi-circuit energy meter includes a housing 1, and a three-phase metering element 2, three single-phase metering elements 3, a three-phase relay 4, and three sets of single-phase relays 5 installed in the housing 1. The housing 1 has an inlet terminal block 6 for connecting an external inlet cable and an outlet terminal block 7 for connecting an external outlet cable. The three-phase metering element 2 and the three-phase relay 4 are located in the three-phase circuit. The three-phase metering element 2 is connected to a three-phase metering unit (which can be an existing three-phase metering circuit) to transmit the collected three-phase current signal to the three-phase metering unit for metering. The three single-phase metering elements 3 are located in their respective single-phase circuits. Each single-phase metering element 3 has a corresponding single-phase relay 5 installed in its single-phase circuit. The outlet terminal of each single-phase metering element 3 is connected to the corresponding single-phase metering unit (which can be an existing single-phase metering circuit) to independently meter the electricity in each single-phase circuit.

[0018] In this embodiment, the three-phase metering element 2 is a three-phase mutual inductor, and the single-phase metering element 3 is a single-phase mutual inductor. The secondary windings of the three-phase mutual inductors 2 are all connected to the corresponding three-phase metering units, and the secondary windings of each single-phase mutual inductor 3 are connected to its corresponding single-phase metering unit. In another preferred embodiment, the metering element may also be a voltage divider resistor, a Hall sensor, etc.

[0019] Combination Figure 2 As shown, in this utility model, the inlet terminal block 6 is located on the top of the housing 1. The inlet terminal block 6 has four inlet terminals, from left to right: phase A inlet terminal, phase B inlet terminal, phase C inlet terminal, and phase N inlet terminal. The spacing between each phase inlet terminal of the inlet terminal block 6 is 60mm to increase electrical clearance. The outlet terminal block 7 is located at the bottom of the housing 1. The terminals on the outlet terminal block 7 are divided into three-phase outlet terminals and single-phase outlet terminals, arranged from left to right. The three-phase outlet terminals include four, in order: phase A outlet terminal, phase B outlet terminal, phase C outlet terminal, and phase N outlet terminal; the single-phase outlet terminals include six, in order: phase A outlet terminal, phase N outlet terminal, phase B outlet terminal, phase N outlet terminal, phase C outlet terminal, and phase N outlet terminal. The spacing between each phase outlet terminal of the outlet terminal block 7 is 20mm. The left side has three-phase ABCN outgoing lines, and the right side has single-phase ANBNCN outgoing lines, which satisfies people's wiring habits and conforms to actual power consumption conditions.

[0020] like Figure 1 As shown, in another preferred embodiment, the three-phase relay 4 and the three-phase metering element 2 are located on the left side inside the housing 1, while the single-phase relay 5 and the single-phase metering element 3 are located on the right side inside the housing 1. Specifically, the three-phase relay 4 is arranged on the left side, in conjunction with the three sets of three-phase current transformers 2 on its right side, and the three single-phase relays 5 are arranged on the right side, in conjunction with the three sets of unidirectional current transformers on its right side, with a vertical spacing of 33mm. The arrangement of the three-phase relay 4 and the single-phase relay 5 minimizes the current flow path inside the energy meter and reduces the impedance, thereby minimizing the voltage drop on the copper busbar and the overall heat generation. Furthermore, the low voltage drop on the copper busbar allows for accurate measurement of the on-site voltage, resulting in more accurate metering.

[0021] In one embodiment of this utility model, the primary windings of the three-phase mutual inductors 2 are respectively connected to the A, B, and C input terminals of the input terminal block 6, and the other end of the primary windings of the three-phase mutual inductors 2 are respectively connected to the A, B, and C phase input terminals of the three-phase relay 4. The N input terminal of the input terminal block 6 is connected to the N phase input terminal of the three-phase relay 4. One end of the primary windings of the three single-phase mutual inductors 3 are respectively connected to the A, B, and C input terminals of the input terminal block 6, and the other end of the primary windings of the three single-phase mutual inductors 3 are respectively connected to the input terminals of the three single-phase relays 5, and the N input terminal of the input terminal block 6 is connected to the N phase input terminal of the three single-phase relays 5. The secondary windings of the three-phase mutual inductors 2 and the three single-phase mutual inductors 3 are all connected to the corresponding metering circuits.

[0022] The A, B, C, and N phase output terminals of the three-phase relay 4 are respectively connected to the A, B, C, and N phase output terminals of the three-phase output terminals of the output terminal block 7; the output terminals of the three single-phase relays 5 are respectively connected to the A, B, and C phase output terminals of the single-phase output terminals of the output terminal block 7, and the N phase output terminals of the three single-phase relays 5 are connected together to the N phase output terminal of the single-phase output terminals of the output terminal block 7.

[0023] The aforementioned wiring configuration describes the arrangement where the three-phase current transformer 2 is located upstream of the three-phase relay 4, and the single-phase current transformer 3 is located upstream of the single-phase relay 5. In practice, the positions of the current transformers and relays can be interchanged; that is, the relays can be located upstream of the current transformers. Specifically, the A, B, and C phase input terminals of the input terminal block 6 are connected to the corresponding input terminals of the three-phase relay 4, and to the input terminals of the three single-phase relays 5, respectively. The output terminals of the three-phase relay 4 are connected to the three-phase output terminals of the output terminal block 7, and are also connected to the input terminals of the three-phase current transformer 2, which outputs three-phase induction signals to the three-phase metering unit. The output terminals of the single-phase relays 5 are connected to the single-phase output terminals of the output terminal block 7, and are also connected to the input terminals of one single-phase current transformer 3, respectively, which output single-phase induction signals to the corresponding single-phase metering units.

[0024] In another preferred embodiment, a central isolation barrier is provided inside the housing 1, located to the right of the three-phase transformer 2 and to the left of the single-phase relay 5, for housing the three ABC incoming and outgoing lines; a right-side isolation barrier is provided inside the housing 1, located between the right side of the single-phase transformer 3 and the right side of the housing 1, for housing the N incoming and outgoing lines and the three ABC single-phase outgoing lines. The central and right-side isolation barriers make the overall assembly of the energy meter more reliable and limit the spacing between the single and three phases inside the energy meter, minimizing their interaction; furthermore, the distance between the three-phase relay 4 and the single-phase relay 5 ensures minimal magnetic field interference between them, thus making the relay tripping and closing more reliable.

[0025] In this utility model, the outer shell 1 includes a bottom shell, an upper shell detachably fastened to the bottom shell, and a transparent flip door on the upper shell. The specific structure of the outer shell 1 adopts existing technology and will not be described in detail here. The inlet terminal block 6 and the outlet terminal block 7 are located outside the bottom shell. The three-phase metering element 2, the single-phase metering element 3, the three-phase relay 4, and the single-phase relay 5 are fixedly installed on the bottom shell. Specifically, the relays (including the three-phase relay 4 and the single-phase relay 5) and the current transformers (including the three-phase current transformer 2 and the single-phase current transformer) can be combined and fixed to the bottom shell by screws and clips.

[0026] In this invention, the outer casing 1 of the electricity meter is a Class II protective insulating enclosure. The upper and lower casings are made of high-weather-resistant PC+(10±2)%GF material, which does not deform at a high temperature of 90℃ and is non-combustible and extinguishable at a temperature of 650℃±10℃. The inlet terminal block 6 and outlet terminal block 7 are made of high-weather-resistant PBT+(30±2)%GF material, which is non-combustible and extinguishable at a temperature of 960℃±15℃, and the heat deformation temperature of the inlet terminal block 6 and outlet terminal block 7 is higher than 200℃. Sealing strips (such as silicone sealing strips) with good environmental adaptability are provided between the upper and lower casings, between the upper casing and the transparent flip door, and between the inlet terminal block 6 and outlet terminal block 7 and the lower casing, forming a closed loop to prevent dust and moisture from entering the casing 1. The entire electricity meter achieves an IP54 dustproof and waterproof rating. The selection of superior weather-resistant engineering materials and the dustproof and waterproof design enable the electricity meter to work reliably for a long time in the temperature range of -40℃ to 70℃, meeting the requirements of harsh climatic conditions such as high and low temperature tests and double 85 tests, with a service life of more than 16 years.

[0027] In another preferred embodiment, an array of heat dissipation holes is provided on the top of the upper shell of the outer casing 1, with a waterproof and breathable membrane embedded in the holes. A heat-conducting cable integrated groove connected to the composite heat dissipation component is provided on the bottom of the lower shell of the outer casing 1. The array of heat dissipation holes and the heat-conducting cable integrated groove facilitate heat dissipation. The combination of the array of heat dissipation holes on the upper shell and the waterproof and breathable membrane ensures IP54 protection while achieving airflow and heat dissipation, avoiding the impact of high temperatures on measurement accuracy and component lifespan.

[0028] More preferably, the middle isolation barrier and the right isolation barrier inside the outer shell 1 are provided with honeycomb-shaped ventilation channels. These ventilation channels, together with the array of heat dissipation holes on the upper shell and the integrated heat conduction groove on the bottom shell, form a three-dimensional ventilation network, which promotes the rise of internal hot air and its exhaust from the array of heat dissipation holes on the top, while external cold air is replenished from the gaps in the bottom shell, forming a natural convection circulation.

[0029] In another preferred embodiment, the multi-loop power meter further includes a composite heat dissipation assembly disposed within the housing 1. The composite heat dissipation assembly includes a graphene composite thermally conductive busbar, a flexible thermally conductive silicone pad, and a graphene thermally conductive strip. The graphene composite thermally conductive busbar is fixed to the bottom housing by insulating bolts. The graphene composite thermally conductive busbar is respectively attached to the tops of multiple heating elements (including three-phase mutual inductors 2, three single-phase mutual inductors 3, three-phase relays 4, and three sets of single-phase relays 5) within the housing 1 via the flexible thermally conductive silicone pad. For example, multiple arc-shaped thermally conductive grooves are formed on the graphene composite thermally conductive busbar, and a flexible thermally conductive silicone pad that is attached to the heating element is embedded in each arc-shaped thermally conductive groove. One end of the graphene thermally conductive strip is connected to the graphene composite thermally conductive busbar, and the other end extends into the thermal conductive integrated groove of the bottom housing and is tightly attached to the bottom housing.

[0030] The above technical solution incorporates a composite heat dissipation component within the outer casing 1. A graphene composite thermal busbar, through a combination of an arc-shaped thermal groove and a flexible thermally conductive silicone pad, achieves precise contact with multiple dispersed heat sources. The graphene composite thermal busbar collects concentrated heat from the three-phase relay 4, three-phase mutual inductor 2, single-phase relay 5, and single-phase mutual inductor 3 via the flexible thermally conductive silicone pad, and then transfers it to the connected graphene thermal strip. The integrated heat transfer groove, by tightly adhering to the graphene thermal strip, rapidly transfers the heat from the graphene thermal strip to the entire bottom shell. The bottom shell, acting as a large-area heat dissipation carrier, can quickly dissipate heat to the external environment, forming a complete heat dissipation chain: "heat source - graphene composite thermal busbar - graphene thermal strip - integrated heat transfer groove - bottom shell - external environment". The combination of graphene composite thermal busbar and flexible thermal silicone pad can be adapted to the irregular surfaces of relays and transformers, realizing the synchronous absorption and uniform diffusion of heat from multiple heat sources. The high thermal conductivity of graphene thermal strips can quickly conduct concentrated heat to the bottom shell. Combined with the integrated groove of the bottom shell thermal strip, the heat dissipation area is expanded, solving the problem of heat accumulation caused by integration.

[0031] In this embodiment, the graphene composite thermal bus adopts a structure of "copper substrate + graphene coating + arc-shaped heat conduction groove," and is elongated in shape, with its length covering the width of all heating elements. The graphene composite thermal bus includes a copper substrate (oxygen-free copper), the surface of which is coated with a 0.1mm thick graphene coating to enhance thermal conductivity. Multiple independent "arc-shaped heat conduction grooves" are formed at the bottom of the graphene composite thermal bus, each adapted to the top contour of the heating element. A flexible thermally conductive silicone pad is embedded in each arc-shaped heat conduction groove. Preferably, a layer of thermally conductive silicone grease (thermal conductivity 5.0W / (m・K)) is first applied into the arc-shaped heat conduction groove, and then the flexible thermally conductive silicone pad is embedded in the arc-shaped heat conduction groove, ensuring a tight fit between the flexible thermally conductive silicone pad and the wall of the arc-shaped heat conduction groove.

[0032] In this embodiment, the heat-conducting strip integrated groove is an elongated groove structure integrally formed inside the bottom shell, made of the same material as the bottom shell. It extends along the arrangement direction of the three-phase relay 4, three-phase mutual inductor 2, single-phase relay 5, and single-phase mutual inductor 3 inside the bottom shell, and its length matches the installation length of the graphene heat-conducting strip. The graphene heat-conducting strip is snapped into the heat-conducting strip integrated groove and fastened to the bottom shell by heat-conducting bolts. A layer of thermally conductive silicone grease is also coated inside the heat-conducting strip integrated groove to reduce the contact thermal resistance between the graphene heat-conducting strip and the heat-conducting strip integrated groove.

[0033] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A multi-circuit energy meter, characterized in that, Includes a housing, and a three-phase metering element, three single-phase metering elements, a three-phase relay, and three sets of single-phase relays installed in the housing; The housing has an inlet terminal block for connecting an external inlet cable and an outlet terminal block for connecting an external outlet cable; The three-phase metering element and the three-phase relay are located in the three-phase circuit. The three-phase metering element is connected to the three-phase metering unit and is used to transmit the collected three-phase current signal to the three-phase metering unit for metering. The three single-phase metering elements are located in their respective single-phase circuits. Each single-phase metering element is connected to a single-phase relay in its single-phase circuit. The output terminal of each single-phase metering element is connected to the corresponding single-phase metering unit to independently measure the electricity of each single-phase circuit.

2. A multi-circuit energy meter according to claim 1, characterized in that, The three-phase metering element is a three-phase mutual inductor, and the single-phase metering element is a single-phase mutual inductor. The secondary windings of the three-phase mutual inductors are all connected to the three-phase metering unit, and the secondary windings of each single-phase mutual inductor are all connected to its corresponding single-phase metering unit.

3. A multi-circuit energy meter according to claim 2, characterized in that, The terminal block is provided with four input terminals, which are, from left to right, phase A input terminal, phase B input terminal, phase C input terminal and phase N input terminal; The terminals on the outgoing terminal block are divided into two parts: three-phase outgoing terminals and single-phase outgoing terminals, arranged in order from left to right. The three-phase outgoing terminals include four terminals, namely, phase A, phase B, phase C, and phase N. The single-phase outgoing terminals include six terminals, namely, phase A, phase N, phase B, phase N, phase C, and phase N.

4. A multi-circuit energy meter according to claim 3, characterized in that, The primary windings of the three-phase mutual inductors are connected to the A, B, and C input terminals of the input terminal block, respectively. The other end of the primary windings of the three-phase mutual inductors is connected to the A, B, and C phase input terminals of the three-phase relays, respectively. The N input terminal of the input terminal block is connected to the N phase input terminal of the three-phase relays. One end of the primary windings of the three single-phase mutual inductors is connected to the A, B, and C input terminals of the input terminal block, respectively. The other end of the primary windings of the three single-phase mutual inductors is connected to the input terminals of the three single-phase relays, respectively. The N input terminal of the input terminal block is connected to the N phase input terminal of the three single-phase relays. The secondary windings of both the three-phase mutual inductors and the three single-phase mutual inductors are connected to the corresponding metering circuits. The A, B, C, and N phase output terminals of the three-phase relays are respectively connected to the A, B, C, and N phase output terminals of the three-phase output terminals of the output terminal block; the output terminals of the three single-phase relays are respectively connected to the A, B, and C phase output terminals of the single-phase output terminals of the output terminal block, and the N phase output terminals of the three single-phase relays are connected together to the N phase output terminal of the single-phase output terminals of the output terminal block.

5. A multi-circuit energy meter according to claim 3, characterized in that, The A, B, and C three-phase input terminals of the input terminal block are connected to the corresponding input terminals of the three-phase relays, and to the input terminals of the three single-phase relays, respectively. The output terminal of the three-phase relay is connected to the three-phase power output terminal of the output terminal block. The output terminal of the three-phase relay is also connected to the input terminal of the three-phase mutual inductor. The three-phase mutual inductor outputs a three-phase induction signal to the three-phase metering unit. The output terminal of the single-phase relay is connected to the single-phase output terminal of the output terminal block. The output terminal of the single-phase relay is also connected to the input terminal of a single-phase mutual inductor. The three single-phase mutual inductors output single-phase sensing signals to the corresponding single-phase metering units.

6. A multi-circuit energy meter according to claim 3, characterized in that, An intermediate isolation barrier is provided in the middle of the interior of the housing for accommodating three ABC incoming and outgoing lines; a right isolation barrier is provided on the right side of the interior of the housing for accommodating N incoming and outgoing lines and three ABC single-phase outgoing lines.

7. A multi-circuit energy meter according to any one of claims 1-6, characterized in that, The three-phase relay and three-phase metering element are located on the left side inside the housing, and the single-phase relay and single-phase metering element are located on the right side inside the housing; And / or the incoming terminal block is located on the top of the housing, and the outgoing terminal block is located on the bottom of the housing.

8. A multi-circuit energy meter according to any one of claims 1-6, characterized in that, The outer casing includes a bottom shell, an upper shell that is detachably fastened to the bottom shell, and a transparent flip door on the upper shell. The inlet terminal block and outlet terminal block are located outside the bottom shell. The three-phase metering element, the single-phase metering element, the three-phase relay, and the single-phase relay are fixedly installed on the bottom shell.

9. A multi-circuit energy meter according to claim 8, characterized in that, The upper and lower shells are made of high weather-resistant PC + (10±2)% GF material, and the inlet and outlet terminal blocks are made of high weather-resistant PBT + (30±2)% GF material.

10. A multi-circuit energy meter according to claim 8, characterized in that, Sealing strips forming closed loops are provided between the upper shell and the bottom shell, between the upper shell and the transparent flip door, and between the inlet terminal block and the outlet terminal block and the bottom shell.

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