A combined junction box for an electrical energy metering self-locking device

Abstract

The application provides a combined junction box for an electric energy metering self-locking device, which comprises a junction box body and a cover plate; wherein the junction box body is provided with current connection terminals, including two current incoming line connection terminals and two current outgoing line connection terminals; one end of a normally open self-locking assembly is connected with one current incoming line connection terminal, and the other end is connected with one current outgoing line connection terminal; one end of a current normally closed self-locking assembly is connected with the other current incoming line connection terminal, and the other end is connected with the other current outgoing line connection terminal; the cover plate is connected with the junction box body in a manner capable of being buckled on the junction box body, and the inner wall of the cover plate is provided with self-locking fixing columns corresponding to the current normally closed self-locking assembly and the normally open self-locking assembly. The current normally closed self-locking assembly and the normally open self-locking assembly are connected, and the self-locking fixing columns arranged on the cover plate are matched, so that the misconnection prevention structure is increased, and the error short circuit of the connecting piece by the operator is eliminated.

Description

Technical Field

[0001] This invention relates to the field of power measurement technology, and more specifically, to a combined junction box for a self-locking power metering device. Background Technology

[0002] The power metering junction box is an important component of the secondary circuit of the power metering device. It is used to calibrate instruments under power conditions and allows for the replacement of secondary circuit equipment without power interruption.

[0003] The electricity metering junction box consists of voltage terminals, current terminals, and voltage and current loop shorting links. It has a compact structure and is widely used, small in size, and low in cost.

[0004] Common electrical junction boxes come in two types: three-phase three-wire and three-phase four-wire, which are used in delta and star connections for metering secondary circuit electrical energy, respectively.

[0005] In recent years, with the improvement of measurement technology and the development of loop status inspection technology, the widespread application of loop status inspection instruments in the field has revealed that abnormal events related to the secondary metering junction box account for the largest proportion of all abnormal events in the secondary metering circuit. Therefore, this issue urgently needs to be addressed. Several problems exist in the junction box design, including the lack of anti-miswiring devices, the absence of self-locking devices for current and voltage connection plates, reliance on manual installation for quality control, and the lack of structural designs to prevent misoperation correction of connection plates. These problems cause the secondary metering circuit to frequently operate in an open-circuit or short-circuit state, posing significant safety hazards. They also result in under-metering or non-metering by the electricity meter, leading to power loss and substantial economic losses, and to some extent affecting the reliability, accuracy, and security of electricity metering. Summary of the Invention

[0006] In view of this, the present invention proposes a combined junction box for an electricity metering self-locking device, which aims to solve the problem that the secondary circuit of the existing metering junction box often operates in an open circuit or short circuit state, posing a significant safety hazard.

[0007] This invention proposes a combined junction box for an electricity metering self-locking device. The combined junction box includes a junction box body and a cover plate. The junction box body is provided with current connection terminals. Each current connection terminal includes two current inlet connection terminals, two current outlet connection terminals, a normally closed self-locking component, and a normally open self-locking component. One end of the normally open self-locking component is connected to one of the two current inlet connection terminals, and the other end is connected to one of the two current outlet connection terminals, enabling the opening or closing of the connection between the two current inlet and outlet connection terminals, and achieving automatic locking between them. One end of the normally closed self-locking component is connected to the other current inlet connection of the two current inlet connection terminals, and the other end is connected to the other current outlet connection of the two current outlet connection terminals. This is used to realize the opening or closing of the other current inlet connection terminal and the other current outlet connection terminal, and to realize the automatic locking of the two. The cover plate is connected to the junction box body in a way that can be fastened to the junction box body. Furthermore, the inner wall of the cover plate is provided with self-locking fixing posts corresponding to the normally closed self-locking component and the normally open self-locking component. These posts are used to press against the corresponding self-locking components when the cover plate is fastened to the junction box body, so that the corresponding self-locking components automatically close or open.

[0008] Furthermore, in the aforementioned combined junction box for the self-locking device of electricity metering, the junction box body is provided with voltage connection terminals; the voltage connection terminals include a voltage input connection terminal, three voltage output connection terminals, and a normally closed voltage self-locking component; wherein, one end of the normally closed voltage self-locking component is connected to the voltage input connection terminal, and the other end is connected to the voltage output connection terminal, for realizing the opening or closing of the voltage input connection terminal and the voltage output connection terminal, and realizing the automatic locking of the two; the inner wall of the cover plate is provided with a self-locking fixing post corresponding to the normally closed voltage self-locking component, for pressing against the corresponding self-locking component when the cover plate is fastened to the junction box body, so that the corresponding self-locking component automatically closes or opens.

[0009] Furthermore, in the aforementioned junction box for the self-locking device of electricity metering, there are four voltage connection terminals, corresponding to phase A, phase B, phase C, and phase N respectively; when the voltage circuit is normally connected, all four normally closed self-locking components of the four voltage connection terminals are in the closed state; when the equipment is replaced, the four normally closed self-locking components are in the open state.

[0010] Furthermore, in the aforementioned junction box for the self-locking device of electricity metering, there are three current connection terminals, corresponding to phase A, phase B, and phase C respectively; when the current circuit is normally connected, all three normally open self-locking devices of the three current connection terminals are in the open state, and all three normally closed self-locking components are in the closed state; when the equipment in the current circuit is replaced, all three normally open self-locking devices are in the closed state, and all three normally closed self-locking components are in the open state.

[0011] Furthermore, in the aforementioned combined junction box for the self-locking device for electricity metering, a lead seal is also provided between the cover plate and the junction box body as a component to prevent disassembly, ensuring that the cover plate is not disassembled without damage.

[0012] Furthermore, in the aforementioned combined junction box for the self-locking device for electricity metering, the main body of the junction box is provided with a box body lead seal screw hole, and the cover plate is provided with a cover plate lead seal screw hole, which corresponds to the box body lead seal screw hole and is used to install the lead seal screw.

[0013] Furthermore, in the aforementioned combined junction box for the self-locking device for electricity metering, the lead-sealed screw hole of the box body is located on one side of the centerline of the junction box body; the lead-sealed screw hole of the cover plate is located on one side of the centerline of the cover plate.

[0014] Furthermore, the aforementioned junction box for the self-locking device for electricity metering also has lead-sealed fixing holes on its cover plate.

[0015] Furthermore, in the aforementioned combined junction box for the self-locking device for electricity metering, the main body of the junction box has a quadrilateral structure, and the main body of the junction box is provided with two junction box fixing holes, which are located at two opposite corners of the main body of the junction box for installing the main body of the junction box onto the electricity meter.

[0016] Furthermore, in the aforementioned combined junction box for the self-locking device for electricity metering, both the junction box body and the cover are transparent, allowing observation of the internal structure and serving to prevent electricity theft.

[0017] The combined junction box for the self-locking device of electricity metering provided by the present invention adopts a four-terminal design for the current connection terminals, which avoids wiring abnormalities caused by the selection of wiring holes due to the six-terminal design, reduces the selection of current circuit wiring terminals, and thus eliminates the probability of incorrect wiring of the current circuit. In addition, the four current input and output terminals are connected by a normally closed self-locking component and a normally open self-locking component, and can be used with the self-locking fixing post set on the cover to increase the anti-misalignment wiring structure, thereby preventing operators from erroneously short-circuiting the connecting pieces.

[0018] Preferably, the voltage input and output terminals are connected by a voltage normally closed self-locking assembly, and can be used in conjunction with the self-locking fixing post on the cover plate to increase the anti-misalignment wiring structure, thereby preventing operators from accidentally short-circuiting the connecting pieces, and ensuring that the cover plate is installed in place while all wiring connections are in place.

[0019] Furthermore, the junction box body adopts a transparent design, which deters some criminals from stealing electricity by altering the internal structure of the junction box. Attached Figure Description

[0020] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0021] Figure 1 This is a schematic diagram of the junction box body in the combined junction box for the self-locking device for electricity metering provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the cover plate in the combined junction box of the self-locking device for electricity metering provided in an embodiment of the present invention. Detailed Implementation

[0023] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] See Figure 1 and Figure 2 This figure illustrates a preferred structure of a combined junction box for an energy metering self-locking device provided by an embodiment of the present invention. As shown, the combined junction box includes: a junction box body 100 and a cover plate 200; wherein,

[0025] The junction box body 100 is provided with voltage connection terminals 102 and current connection terminals 103. Specifically, the junction box body 100 can be a transparent part, i.e., it adopts a transparent design to observe the internal structure and to prevent electricity theft. In this embodiment, the junction box body 100 is provided with two pre-embedded nuts, which are installed at the first box body lead-seal screw hole 101 and the second box body lead-seal screw hole 105 for connecting lead-seal screws.

[0026] The voltage connection terminal 102 includes a voltage input connection terminal, three voltage output connection terminals, and a normally closed self-locking voltage assembly. One end of the normally closed self-locking voltage assembly is connected to the voltage input connection terminal, and the other end is connected to the voltage output connection terminal. It is used to realize the opening or closing of the voltage input connection terminal and the voltage output connection terminal, and to realize the automatic locking of the two.

[0027] In this embodiment, there are four voltage connection terminals 102, corresponding to phases A, B, C, and N, respectively, to control the four-phase voltage. Each of the four voltage connection terminals 102 has one voltage input connection terminal and three voltage output connection terminals, and the voltage input connection terminal and the three voltage output connection terminals are connected by a normally closed self-locking voltage assembly. The voltage connection terminals 102 adopt a one-in-three-out design to ensure the connection of the voltage lines of the energy meter, the dedicated transformer terminal, and the circuit status monitoring instrument in the secondary voltage circuit of the metering junction box. The normally closed self-locking voltage assembly cooperates with the cover plate 200 to ensure that the voltage circuit is normally closed after the metering junction box is correctly connected.

[0028] like Figure 1 As shown, the voltage connection terminal 102 corresponding to phase A has a phase A voltage input connection terminal Ua, a first phase A voltage output connection terminal Ua1, a second phase A voltage output connection terminal Ua2, and a third phase A voltage output connection terminal Ua3, which are respectively connected to the secondary voltage circuit of the energy meter, the dedicated transformer terminal, and the voltage line of the circuit status monitoring instrument. Furthermore, the phase A voltage input connection terminal Ua is connected to the first phase A voltage output connection terminal Ua1, the second phase A voltage output connection terminal Ua2, and the third phase A voltage output connection terminal Ua3 through a phase A voltage normally closed self-locking component K1. The phase A voltage normally closed self-locking component K1 is connected to the phase A voltage input connection terminal Ua and the phase A voltage output connection terminals Ua1, Ua2, and Ua3, respectively, and serves to disconnect or close the voltage Ua and automatically lock it. By cooperating with the cover plate 200 to press the phase A voltage normally closed self-locking component K1, it is kept closed.

[0029] The voltage connection terminal 102 corresponding to phase B has a phase B voltage input connection terminal Ub, a first phase B voltage output connection terminal Ub1, a second phase B voltage output connection terminal Ub2, and a third phase B voltage output connection terminal Ub3. Furthermore, the phase B voltage normally closed self-locking component K4 is connected to the phase B voltage input connection terminal Ub and the phase B voltage output connection terminals Ub1 / Ub2 / Ub3 respectively. The voltage connection terminal 102 corresponding to phase C has a phase C voltage input connection terminal Uc, a first phase C voltage output connection terminal Uc1, a second phase C voltage output connection terminal Uc2, and a third phase C voltage output connection terminal Uc3. The voltage output connection terminal Uc3 is connected to the C-phase voltage input connection terminal Uc and the C-phase voltage output connection terminals Uc1 / Uc2 / Uc3 respectively. The voltage connection terminal 102 corresponding to the N-phase has an N-phase voltage input connection terminal Un, a first N-phase voltage output connection terminal Un1, a second N-phase voltage output connection terminal Un2, and a third N-phase voltage output connection terminal Un3. The N-phase voltage normally closed self-locking component K10 is connected to the N-phase voltage input connection terminal Un and the N-phase voltage output connection terminals Un1 / Un2 / Un3 respectively.

[0030] In this embodiment, K4, K7, and K10 have the same function as K1, controlling the voltages of phases B, C, and N. When the voltage circuit is normally connected, the four normally closed self-locking components of the four voltage connection terminals, namely K1, K4, K7, and K10, are all in the closed state. When replacing equipment, the four normally closed self-locking components, namely K1, K4, K7, and K10, are in the open state.

[0031] The current connection terminal 103 includes two current input connection terminals, two current output connection terminals, a normally closed self-locking component, and a normally open self-locking component. One end of the normally open self-locking component is connected to one of the two current input connection terminals, and the other end is connected to one of the two current output connection terminals. This allows for the opening or closing of the connection between the two current input and output connection terminals, and enables automatic locking between them. Similarly, one end of the normally closed self-locking component is connected to the other current input connection terminal, and the other end is connected to the other current output connection terminal. This allows for the opening or closing of the connection between the other current input and output connection terminals, and enables automatic locking between them.

[0032] In practical implementation, there are three current connection terminals 103, corresponding to phases A, B, and C respectively, to control the three-phase current. Each of the three voltage connection terminals 102 has two voltage input connection terminals and two voltage output connection terminals, and they are connected via a normally closed self-locking component and a normally open self-locking component. The normally closed and normally open self-locking components employ a normally open and normally closed self-locking design and cooperate with the cover plate to ensure that after the metering junction box is correctly connected, the current circuit will not experience short circuits or open circuits.

[0033] like Figure 1 As shown, the current connection terminal 103 corresponding to phase A has a first phase A current inlet connection terminal Ia1, a second phase A current inlet connection terminal Ia3, a first phase A current outlet connection terminal Ia2, and a second phase A current outlet connection terminal Ia4. The phase A normally open self-locking component K2 is connected to phase A current terminals Ia1 and Ia2 respectively, serving to open and close the connection between Ia1 and Ia2 and to automatically lock. It is kept open by pressing the phase A normally open self-locking component K2 against the cover plate 200. The phase A normally closed self-locking component K3 is connected to phase A current terminals Ia2 and Ia4 respectively, serving to open and close the connection between Ia2 and Ia4 and to automatically lock. It is kept closed by pressing the self-locking device against the cover plate.

[0034] The current connection terminal 103 corresponding to phase B has a first phase B current inlet connection terminal Ia1, a second phase B current inlet connection terminal Ib3, a first phase B current outlet connection terminal Ib2, and a second phase B current outlet connection terminal Ib4. Furthermore, the normally open self-locking component K5 of phase B is connected to phase B current terminals Ib1 and Ib2 respectively, and the normally closed self-locking component K6 of phase B is connected to phase B current terminals Ib2 and Ib4 respectively. The current connection terminal 103 corresponding to phase C has a first phase C current inlet connection terminal Ic1, a second phase C current inlet connection terminal Ic3, a first phase C current outlet connection terminal Ic2, and a second phase C current outlet connection terminal Ic4. Furthermore, the normally open self-locking component K9 of phase C is connected to phase C current terminals Ic1 and Ic2 respectively, and the normally closed self-locking component K1 of phase C is connected to phase C current terminals Ic2 and Ic4 respectively.

[0035] In this embodiment, K5 and K8 function the same as K2, controlling the current of phases B and C. Similarly, K6 and K9 function the same as K3, controlling the current of phases B and C. The four-terminal design of the current connection terminal 103 avoids wiring abnormalities caused by the six-terminal design. In other words, the current connection terminal uses a two-in, two-out wiring method to eliminate redundant terminals and ensures that incorrect wiring occurs during installation. When the current circuit is normally connected, the three normally open self-locking devices of the three current connection terminals 103, namely K2, K5, and K6, are all in the open state, and the three normally closed self-locking components, namely K3, K6, and K7, are all in the closed state. Taking phase A as an example, since K2 is open, Ia1 enters and Ia3 exits, passing through the equipment. After exiting the equipment, Ia4 enters, and since K3 is closed, Ia2 exits. When the equipment in the current circuit is replaced, the three normally open self-locking devices, namely K2, K5 and K6, are all in the closed state, and the three normally closed self-locking components, namely K3, K6 and K7, are all in the open state. Taking phase A as an example, since K2 is closed, Ia1 enters and Ia2 exits, entering the transformer to form a closed circuit.

[0036] In this embodiment, the current terminals are misaligned, which enables live circuit breaking and short-circuiting functions, facilitating live replacement of field equipment.

[0037] The cover plate 200 is connected to the junction box body 100 in a manner that allows it to be snapped onto the junction box body 100. Furthermore, the inner wall of the cover plate 200, i.e., the wall facing the junction box body 100 after installation, is provided with self-locking fixing posts. These posts correspond to normally closed voltage self-locking components, normally closed current self-locking components, and normally open self-locking components. When the cover plate 200 is snapped onto the junction box body 100, they press against the corresponding self-locking components, causing the corresponding self-locking components to automatically close or open. Specifically, the cover plate 200 can be a transparent piece, i.e., a transparent cover plate, used to seal the junction box body 100. It is normally stationary and open, and the transparent design of the cover plate 200 facilitates observation of the wiring inside the junction box.

[0038] like Figure 1 As shown, ten self-locking fixing posts are provided on the inner wall of the cover plate 200, namely the first self-locking fixing post 203, the second self-locking fixing post 204, and the tenth self-locking fixing posts 212, which correspond one-to-one with K1, K2, and K10 respectively. They are used for the crimping function of self-locking switches K1, K2, K3, K4, K5, K6, K7, K8, K9, and K10, and play a role in automatic closing and opening, avoiding errors caused by personnel forgetting to short-circuit or short-circuiting. Among them, the self-locking fixing posts cooperate with the self-locking components to complete the self-locking, ensuring that the cover plate is installed in place and the secondary circuit of the metering junction box can be automatically restored to the correct connection state.

[0039] In this embodiment, a lead seal (not shown in the figure) is also provided between the cover plate 200 and the junction box body 100 as an anti-disassembly component, ensuring that the cover plate 200 is not detachable without damage. Specifically, the cover plate 200, together with the lead seal and lead seal screws, serves to prevent electricity theft. The lead seal and lead seal screws are used as anti-disassembly components.

[0040] In this embodiment, as Figure 1 As shown, the junction box body 100 is provided with two lead-sealing screw holes, namely a first lead-sealing screw hole 101 and a second lead-sealing screw hole 105, which are symmetrically arranged on the left and right sides of the junction box body 100, and both are located on one side of the center line of the junction box body 100 (e.g., Figure 1 (as shown on the upper side); as Figure 2 As shown, the cover plate 200 is provided with cover plate lead seal screw holes, which correspond to the lead seal screw holes of the box body for installing lead seal screws, thus realizing the connection between the cover plate 200 and the junction box body 100; there can be two cover plate lead seal screw holes, namely the first cover plate lead seal screw hole 202 and the second cover plate lead seal screw hole 213, which correspond one-to-one with the first box body lead seal screw hole 101 and the second box body lead seal screw hole 105, respectively. The first cover plate lead seal screw hole 202 and the second cover plate lead seal screw hole 213 are both located on one side of the center line of the junction box body 100 (e.g., Figure 1 (As shown on the upper side). Meanwhile, as... Figure 2 As shown, the cover plate 200 is also provided with lead seal fixing holes. There can be two lead seal fixing holes, namely the first lead seal fixing hole 201 and the second lead seal fixing hole 214, for installing the lead seal wire. After the cover plate is connected to the main body, the lead seal wire of the lead seal is fixed through the first lead seal fixing hole 201, the second lead seal fixing hole 214, and the hole of the lead seal screw, so that it cannot be disassembled without damage.

[0041] See also Figure 1 The junction box body 100 has a quadrilateral structure and two junction box fixing holes, namely the first junction box fixing hole 104 and the second junction box fixing hole 106. The two junction box fixing holes are located at two opposite corners of the junction box body 100 (e.g., Figure 1 The junction box body 100 is installed on the electricity meter at the lower left and upper right corners shown.

[0042] Each self-locking component can be a switch mechanism with a spring on it, which can achieve automatic locking.

[0043] In summary, the combined junction box for the self-locking device of electricity metering provided in this embodiment adopts a four-terminal design for the current connection terminals, which avoids wiring abnormalities caused by the selection of wiring holes due to the six-terminal design, reduces the selection of current circuit wiring terminals, and thus eliminates the probability of incorrect wiring of the current circuit. Furthermore, the four current input and output terminals are connected by a normally closed self-locking component and a normally open self-locking component, and can be used in conjunction with the self-locking fixing post set on the cover plate to increase the anti-misalignment wiring structure, thereby preventing operators from incorrectly short-circuiting the connecting pieces.

[0044] Preferably, the voltage input and output terminals are connected by a voltage normally closed self-locking assembly, and can be used in conjunction with the self-locking fixing post on the cover plate to increase the anti-misalignment wiring structure, thereby preventing operators from accidentally short-circuiting the connecting pieces, and ensuring that all wiring connections are in place at the same time as the cover plate is installed.

[0045] Furthermore, the junction box body adopts a transparent design, which deters some criminals from stealing electricity by altering the internal structure of the junction box.

[0046] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0047] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0048] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A combined junction box for an electricity metering self-locking device, characterized in that, include: Junction box body and cover; among which, The junction box body is provided with current connection terminals; The current connection terminal includes two current input connection terminals, two current output connection terminals, a normally closed self-locking component, and a normally open self-locking component; wherein, one end of the normally open self-locking component is connected to one of the two current input connection terminals, and the other end is connected to one of the two current output connection terminals, for realizing the opening or closing of one current input connection terminal and one current output connection terminal, and realizing the automatic locking of the two; One end of the normally closed self-locking current component is connected to the other current input connection of the two current input connection terminals, and the other end is connected to the other current output connection of the two current output connection terminals. It is used to realize the opening or closing between the other current input connection terminal and the other current output connection terminal, and to realize the automatic locking between the two. The cover plate is connected to the junction box body in a manner that allows it to be snapped onto the junction box body. Furthermore, the inner wall of the cover plate is provided with self-locking fixing posts corresponding to the normally closed self-locking component and the normally open self-locking component. These posts are used to press against the corresponding self-locking components when the cover plate is snapped onto the junction box body, so that the corresponding self-locking components can automatically close or open. When the current loop is normally connected, the normally open self-locking component is in the open state, and the normally closed self-locking component is in the closed state. When replacing equipment in the current loop, the normally open self-locking component is in the closed state, and the normally closed self-locking component is in the open state.

2. The combined junction box for a self-locking device for electricity metering according to claim 1, characterized in that, The junction box body is equipped with voltage connection terminals; The voltage connection terminal includes a voltage input connection terminal, three voltage output connection terminals, and a normally closed self-locking voltage assembly; wherein, one end of the normally closed self-locking voltage assembly is connected to the voltage input connection terminal, and the other end is connected to the voltage output connection terminal, which is used to realize the opening or closing of the voltage input connection terminal and the voltage output connection terminal, and to realize the automatic locking of the two. The inner wall of the cover plate is provided with a self-locking fixing post corresponding to the normally closed self-locking component, which is used to press against the corresponding self-locking component when the cover plate is fastened to the junction box body, so that the corresponding self-locking component automatically closes or opens.

3. The combined junction box for a self-locking device for electricity metering according to claim 2, characterized in that, The voltage connection terminals are four, corresponding to phase A, phase B, phase C, and phase N respectively; When the voltage circuit is normally connected, all four normally closed self-locking components of the four voltage connection terminals are in the closed state. When replacing equipment, the four normally closed self-locking voltage components are in the open state.

4. The combined junction box for an energy metering self-locking device according to any one of claims 1 to 3, characterized in that, There are three current connection terminals, corresponding to phase A, phase B, and phase C respectively; When the current loop is normally connected, all three normally open self-locking components of the three current connection terminals are in the open state, and all three normally closed self-locking components are in the closed state. When replacing equipment in the current loop, all three normally open self-locking components are in the closed state, and all three normally closed self-locking components are in the open state.

5. The combined junction box for an energy metering self-locking device according to any one of claims 1 to 3, characterized in that, A lead seal is also provided between the cover plate and the junction box body as a component to prevent disassembly, so that the cover plate cannot be disassembled without damage.

6. The combined junction box for a self-locking device for electricity metering according to claim 5, characterized in that, The junction box body is provided with box body lead seal screw holes, and the cover plate is provided with cover plate lead seal screw holes, which correspond to the box body lead seal screw holes and are used to install the lead seal screws.

7. The combined junction box for a self-locking device for electricity metering according to claim 6, characterized in that, The lead-seal screw hole of the box body is located on one side of the centerline of the junction box body; The lead-seal screw holes of the cover plate are located on one side of the centerline of the cover plate.

8. The combined junction box for a self-locking device for electricity metering according to claim 5, characterized in that, The cover plate is also provided with lead seal fixing holes.

9. The combined junction box for an energy metering self-locking device according to any one of claims 1 to 3, characterized in that, The junction box body has a quadrilateral structure and two junction box fixing holes are provided on the junction box body. The two junction box fixing holes are located at two opposite corners of the junction box body and are used to install the junction box body onto the electricity meter.

10. The combined junction box for an energy metering self-locking device according to any one of claims 1 to 3, characterized in that, Both the junction box body and the cover are transparent, allowing observation of the internal structure and serving to prevent electricity theft.

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