JP2004319416A - Air molded break switch for underground distribution - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air molded break switch for underground distribution capable of reducing the cost while keeping various characteristics required for a switch for underground distribution by avoiding the use of a member causing the increase in cost. <P>SOLUTION: Holes are bored in the upper and lower surfaces of a box with an opened front surface, bushings are provided in each hole of the box to form an upper bushing part 8 and a lower bush part 9, electrode rods are mounted on the upper bushing part 8 and the lower bushing part 9, and a movable blade electrode and a fixed blade electrode are provided on each of the electrode rods to constitute a single pole mold contact part. Three phases of the thus-constituted single pole mold contact parts are arranged, and a three-phase integrated mechanism board 30 is set on each opening edge of the front of the box. Three drive levers 26 connected to an operation mechanism provided on the mechanism board 30 are inserted to each box through each opening part 30a of the mechanism board 30 and rotatably supported on each insulating rod. Each insulating rod is rotated by operating the operation mechanism part to rotate all the movable blade electrodes, and the movable blade electrodes are attached to and detached from the fixed blade electrodes to open and close the three poles in interlocking. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded switch used for opening and closing a high-voltage underground distribution line installed inside a power supply box such as a high-voltage cabinet.
[0002]
[Prior art]
Conventionally, a power distribution supply box C in which a large number of molded disconnecting switches E are installed for branching and opening and closing high-voltage underground distribution lines shown in FIGS. 12 and 13 has been used. Inside the power distribution supply box C, three-pole type mold disconnectors E are provided side by side, and a molded bus bar F is connected to an electric wire connection terminal above each of these mold disconnectors E for each of the three phases. Thus, a three-branch circuit is formed, and an underground cable G started up from underground is connected to an electric wire connection terminal below the molded disconnector E of each circuit.
This mold disconnector E is provided with two L-shaped fixed electrodes attached to each other, and covers these L-shaped fixed electrodes with a closing lid to open and close the disconnector. Each L-shaped fixed electrode is provided with a tulip-type contact, An arc-extinguishing cylinder is provided on the outside thereof and an arc-extinguishing rod is provided on the inner periphery thereof so as to be swingable. An electric field relaxation process is also performed, and these fixed electrodes and one closing lid are insulated and molded. In the three-pole opening / closing operation, three phases are simultaneously opened / closed using a detachable operation tool.
[0003]
[Problems to be solved by the invention]
In recent years, demands for reduction of electricity rates have been increasing in society, and reduction of the cost of power distribution equipment has been required to contribute to the reduction of electricity rates. Also, there is a demand for a reduction in cost of a power distribution switch. In the conventional mold disconnecting device, for example, four tulip-type contacts are used corresponding to the disconnecting device 1, the metal mold is applied to the epoxy mold, and the closing for opening and closing is performed. Points that require a lid are raised.
[0004]
In addition to cost, the opening and closing operation mechanism is contained in a storage box, so it is heavy, and the closing lid mold is heavy, the operation sound at the time of opening and closing is large, the narrow arc extinguishing using arc extinguishing rod and arc extinguishing cylinder Because it is a system, there was a risk of damage due to the impact of opening and closing operations.
[0005]
Therefore, the present invention reduces costs while avoiding as much as possible the members that cause a cost increase, and maintaining various characteristics, handling workability, operability, reliability, and the like required by the conventional underground power distribution switch. An object of the present invention is to provide a submersible mold switch for underground power distribution that can solve the above-mentioned problems.
[0006]
[Means for Solving the Problems]
The invention according to claim 1 is characterized in that a box body is erected with flat both sides left and right sides, a front face of the box body is set as an opening surface, and through holes are formed in the upper and lower surfaces of the erected box body. A fixed electrode rod fixed by providing a bush of a fixed length on the outer surface portion of each of the two through holes to form an upper bushing portion and a lower bushing portion, a terminal portion provided at one end, and a fixed blade electrode provided at the other end. The blade electrode is provided with an arc-extinguishing chamber body having a slit-shaped arc-extinguishing chamber, and the fixed electrode rod has its terminal portion in the upper bushing outside the box body and the electrode portion inside the box body. Attachment, a terminal part is provided at one end, and a movable electrode rod which rotatably supports a substantially L-shaped movable blade electrode is provided at the other end, and the terminal part of the movable electrode rod is connected to a lower bushing outside the box body. Inside the box, attach the electrode to the movable blade And rotatably supporting the one end of the insulating rod rotatably to the end is not a movable contact.
[0007]
The single-pole molded contact portions having these structures are arranged in a three-phase arrangement at a predetermined interval, and are aligned with the shape and position of the front opening surface of each of the boxes at the opening edges of the front of these boxes. The three-phase integrated mechanism board provided with an opening of substantially the same shape and the same size is attached to the ground, and the other ends of three drive levers each having one end connected to an operating mechanism provided on the mechanism board, Each of the insulating rods is rotatably supported on the other end of each of the insulating rods by being inserted into each of the boxes from each of the openings of the mechanism substrate, and each of the insulating rods is rotated by operating the operating mechanism, and These movable blade electrodes are rotated together, and each movable blade electrode and each fixed blade electrode are attached and detached to form an underground power distribution mold switch that opens and closes in an interlocked manner with three poles.
[0008]
The invention according to claim 2 is characterized in that each of the boxes is not subjected to an electric field relaxation treatment, is not inserted with a conductor inside, is formed of a single phase of an insulating resin material, and each phase is separated into three phases. The underwater mold switch for underground power distribution according to claim 1 is provided.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 8 show an embodiment of the present invention. Each of the three single-pole molded contact portions B constituting the aerial molded switch (hereinafter referred to as "mold switch") A for underground power distribution according to the present invention is a flat resin molded integrally with an insulating material without performing electric field relaxation treatment. The box body 1 is erected and its two flat surfaces are provided as left and right side surfaces. The vertically elongated rectangular front surface of the erected box body 1 is defined as an opening surface 2, and the upper edge of the opening surface 2 and The lower edge is extended vertically and provided as a thick flange portion 3, and two embedding nuts 4 are provided side by side on the front side of these places. As shown in FIG. 3, the upper surface and the lower surface of the standing box body 1 are slightly shifted rearward on the upper surface side and slightly shifted forward on the lower surface side, respectively, to form through holes 5 and 6, respectively. Short embedding pipes 7 are fitted into the inner circumferences of the through holes 5 and 6, respectively, and a cylindrical bushing having a fixed length is provided on the periphery where the upper and lower embedding pipes 7 are provided. 9 are formed.
[0010]
As shown in FIG. 4, an upper terminal section 10 having a semicircular cross section is provided at the upper end as an electrode section to be attached to the upper bushing section 8, a screw section 11 follows the upper terminal section 10, and the lower end has a U-shape. , A fixed contact of a fixed blade electrode 13 is provided at the lower end of the U-shaped conductor 12, and a fixed electrode rod 14 formed by these. Further, as an arc-extinguishing chamber body 15 to cover the fixed blade electrode 13 of the fixed electrode rod 14, a narrow arc-extinguishing chamber 16a provided by joining two horizontally long plate bodies 16 with their upper ends facing each other with a gap therebetween. Is provided with an arc-extinguishing iron core 16b formed by folding a flat plate into a U-shape. This fixed electrode rod 14 is inserted from the inside of the box 1, and the upper terminal 10 of the fixed electrode rod 14 is passed through the inside of the embedding tube 7 in the upper bushing section 8 as shown in FIG. The fixed blade electrode 13 is inserted inside the box body 1, and the flat screw 17, the spring washer 18, and the hexagon nut 19 are put on the screw portion 11 of the upper terminal portion 10 on the outside in this order, and tightened and fixed. I have.
[0011]
As shown in FIG. 5, a lower terminal portion 20 having a semicircular cross section is provided at the lower end as an electrode portion to be attached to the lower bushing portion 9, and a screw portion 21, a conductor 22 with a lower terminal, A movable electrode rod 24 rotatably supported near the end of the substantially L-shaped movable blade electrode 23 on the side other than the movable contact is provided at the upper portion. One end of an insulating rod 25 is rotatably supported on the portion, and the other end of the insulating rod 25 is connected to the other end of a drive lever 26 (see FIG. 6) having one end fixed to an interlocking shaft 32 described later. It is movably supported. Then, the movable electrode rod 24 is inserted from the inside of the box 1, and as shown in FIG. 6, the lower terminal portion 20 of the movable electrode rod 24 is passed through the inside of the embedded tube 7 into the lower bushing section 9. The movable blade electrode 23 is inserted inside the box 1, and the flat screw 27, the spring washer 28, and the hexagonal nut 29 are put on the screw portion 21 of the lower terminal portion 20 on the outside in this order, and fixed by tightening. .
[0012]
As shown in FIG. 1, the single-pole molded contact portions B formed in this manner are arranged in a three-phase manner with an interval therebetween, and the ends of three opening surfaces 2 (see FIG. A substantially square mechanism board 30 that is grounded is provided on the edge via a packing 2a (see FIG. 6 or 8) of each phase alone made of an insulating material. The mechanism substrate 30 is provided with openings 30a of substantially the same shape and size corresponding to the shape and position of each opening surface 2 on the front face of each single-pole molded contact portion B, and the upper and lower openings of each single-pole molded contact portion B are provided. A mechanism board 30 is fixed to each single-pole molded contact portion B by inserting and tightening a bolt 31 into a through hole provided at a position of the embedded nut 4 provided in the flange portion 3 in advance. Further, the upper edge 30b of the mechanism board 30 is bent at a substantially right angle to the upper surface side of each box body 1. When the mechanism board 30 is mounted on the front of the single-pole mold contact section B, the box of the single-pole mold contact section B The left and right side edges 30c of the mechanism board 30 are also bent at substantially right angles so as to have the strength of the entire mold switch A. Further, two through holes 30d for screwing bolts for mounting the mold switch A to the power distribution supply box C are formed at upper and lower ends of the three openings 30a of the mechanism board 30, respectively.
[0013]
At the upper edge of the three openings 30a of the mechanism board 30, four mountain-shaped locking pieces 30f are provided, and these locking pieces 30f are respectively provided with through holes, and an interlocking shaft is formed in the through holes. One end of each of the three drive levers 26 is fixed to the interlocking shaft 32, and the other end of each of the drive levers 26 is inserted into the box 1 through the opening 30a. It is rotatably supported on the other end of the insulating rod 25 in each single-pole molded contact portion B. As shown in FIGS. 6 and 7, a mechanism section including the interlocking shaft 32 and a mechanism (not shown) for rotating the interlocking shaft 32 is covered with a box-shaped cover 33. On the surface of the cover 33, indications of "ON" and "OFF" for opening and closing are provided, and an indicator 34 for indicating "ON" and "OFF" is provided in conjunction with opening and closing of the mold switch A. ing.
[0014]
Aside from the indicator 34, an operating shaft 50 is provided in a hole 33a provided in the cover 33, a separate handle (not shown) is fitted to the operating shaft 50, and the handle is turned to operate. By rotating the interlocking shaft 32, the respective driving levers 26 are rotated by the rotation of the interlocking shaft 32, and the respective movable blade electrodes 23 are simultaneously rotated, so that the respective movable blade electrodes 23 are fixed to the respective fixed blade electrodes 23. By attaching and detaching the blade electrode 13, each of the single-pole molded contact portions B is opened / closed in conjunction with three poles.
[0015]
Specifically, when the indicator 34 indicates "OFF", the state is as shown in FIG. In this state, when the operating shaft 50 is rotated clockwise by the handle, the interlocking shaft 32 rotates clockwise in FIG. 6, and the respective drive levers 26 rotate downward as shown in FIG. As a result, the respective insulating rods 25 move downward, and the respective drive levers 26 and the insulating rods 25 become linear, thereby simultaneously connecting the respective movable blade electrodes 23 to the upper fulcrum of the supported movable electrode rods 24. , And the movable contact at the tip of each movable blade electrode 23 is connected to the fixed contact of each fixed blade electrode 13 through each narrow arc-extinguishing chamber 16a.
[0016]
When the operating shaft 50 is rotated counterclockwise in FIG. 7 by the handle, the interlocking shaft 32 rotates counterclockwise from the above-mentioned "in" state shown in FIG. 8, and as shown in FIG. Each drive lever 26 pivots upward, and accordingly, each insulating rod 25 moves upward, and each drive lever 26 and insulating rod 25 are bent, and accordingly, each movable blade electrode 23 is moved. Is pivoted downward about a pivot point above the supported movable electrode rod 24, and the movable contact of each movable blade electrode 23 is separated from the fixed contact of the fixed blade electrode 13 of each fixed electrode rod 14. Then, the movable blade electrode 23 is located at the bottom of the box 1 of the single-pole molded contact point B through each of the narrow arc extinguishing chambers 16a.
[0017]
In order to install this mold switch A in the power distribution supply box C, it is installed using a mounting bracket D as shown in FIGS. This mounting bracket D has two side plates 34 each having a trapezoidal shape and having a protruding piece 34a with a part of the upper side protruding in a rectangular shape. It is erected at an interval so as to form a gap with the side surface, and between the two single-pole molded contact portions B provided in parallel with each other, two mounting plates 35 having substantially the same shape and size as the side plate 34 are provided. An angle member 36 is placed from above on each side plate 34 and each protruding piece 34a of each mounting plate 35 (each protruding piece of the mounting plate 35 is not shown). Is fixed. On the front surface of the angle member 36, four bolts 38 used for fixing the mounting bracket D are screwed to a disconnecting switch mounting angle 37 provided in the power distribution supply box C. A screw hole 40 for screwing a bolt 39 used when mounting the mold switch A is provided in the upper and lower portions on the front of the two mounting plates 35, and the upper piece of the mounting plate 35 has A projection 40a provided with a screw hole 40 is provided.
[0018]
In order to mount the mold switch A on the mounting bracket D mounted on the disconnecting switch mounting angle 37 of the power distribution supply box C, each of the mounting plates 35 is provided with a three-phase single-pole molded contact portion B in each gap. And insert it all the way. At this time, the upper edge 30b of the mechanism board 30 of the mold switch A is locked and temporarily placed on each of the projecting portions 40a of the upper pieces of the two mounting plates 35, and the upper and lower screw holes 40 of each mounting plate 35 are molded. The positions of the screw holes 30d provided in the mechanism board 30 of the switch A are aligned, and bolts 39 are screwed into these screw holes 30d and 40, respectively, to fix the mold switch A to the mounting bracket D. Thereby, the mold switch A is installed in the power distribution supply box C as shown in FIG.
In addition, a bus bar with another mold switch A or a porcelain disconnecting switch H is connected to an upper terminal portion 10 in each upper bushing 8 of the mold switch A, and is connected to a lower terminal portion 20 in each lower bushing 9. Is for connecting a rising cable from underground. Note that no ground layer is provided at the ends of these busbars and cables.
[0019]
By using the mold switch A of this embodiment, the following effects can be obtained.
First, since the single-pole molded contact portions B with built-in contacts are separated from each other with a space therebetween, the single-pole molded contact portions B are independently attached to one grounded mechanism board 30 for each phase. It becomes a complete ground fault priority structure. The mechanism board of the mounting surface of each single-pole molded contact portion is grounded, and a bus bar connected to the terminal portion in the upper bushing of each of the single-pole molded contact portions and an underground cable connected to the terminal portion in the lower bushing. Each terminal was not provided with a ground layer, and the upper and lower bushing portions were covered with an insulating rubber cover, and the upper edge of the mechanism board was bent at a substantially right angle at a constant width. It serves as a prevention cover, and at the normal level of contamination in the outer box, it becomes unnecessary to reduce the electric field such as metallikon, conductive paint, and shield in the single-pole molded contact portion B and to provide a ground fault priority structure.
[0020]
Since the grounding layer is not applied to the single-pole molded contact portion B, the corona level is high, and it is difficult for the single-pole molded contact portion B to develop into a ground fault even if soiled or cracked. Since the single-pole molded contact portion B has a narrow box structure, the thickness can be reduced, and the weight and width of the switch can be reduced. Since the single-pole mold contact portion B is small and has a simple shape, APG (pressure gelation) processing is facilitated, and the cost of mold and molding can be reduced. Since the mold is molded, the error in the in-phase direction inner diameter can be reduced, and the adjustment of the fitting position of the fixed electrode and the movable electrode in the narrow box 1 becomes unnecessary, and the fixed electrode and the movable electrode assembled outside are fitted. In this state, it is only necessary to fix the respective electrodes with nuts from the outside, thereby reducing the number of assembly steps in the factory and eliminating the need for conductor inserts during molding.
[0021]
Since the periphery of the switching contact is covered with an integrally molded insulating resin, the breaking performance is increased. The opening surface 2 of the single-pole molded contact portion B and the opening 30a of the mechanism substrate 30 corresponding to the opening surface 2 have a large area, and are connected to the three-phase integrated or multiple circuit integrated box 1, so that when current is interrupted, Replacement with fresh air is smooth, and the number of load currents is increased. When only one line of the mold switch A is grounded, it is difficult to shift to another phase (short circuit). Even if the one-phase side surface of the single-pole molded contact portion B is damaged, a short circuit does not occur. In the case of an internal short circuit in the mold switch A, the pressure is released from the periphery of the cover 33 of the operating mechanism first, and when the internal pressure drops, the side surface of the resin box 1 is cracked mainly by heat. Scattering of the thing outside the power distribution supply box C is suppressed. At that time, the conductive material such as carbide on the inner insulating surface of the box 1 is blown off to the outside of the mold switch A, so that the possibility of insulating recovery at the time of re-transmission of power is increased.
[0022]
Since the insulating support for the internal contact of the single-pole molded contact portion B can be omitted, the vertical direction of the molded switch A can be shortened, and the weight of the switch can be reduced and the cable processing space can be expanded. The gap between the different phases can be used as a space for passing the mounting plate 35 of the mounting bracket D. Further, when the box body 1 ruptures when the mold switch A is short-circuited inside, the mounting plate 35 suppresses the shards from being scattered, and both side plates 34 spread to adjacent circuits (including equipment). It is a protection plate for prevention, an electric shock prevention plate and a complete ground fault priority structure. By dividing the mold switch A and the mounting bracket D together with the weight reduction of the mold switch A, the on-site replacement work of the disconnector in the existing power distribution supply box and the circuit of the mold switch A can be performed by mechanical force. It can be done by one person without using it. The same contact built-in single pole molded contact portion B can be used for a switch having a different pitch between different phases and a switch integrated with a plurality of circuits. If necessary components such as a sensor and a mechanism are added to the single-pole molded contact portion B, a switch having an SOG (ground fault trip type with overcurrent storage trip) function and an automatic switch can be configured in addition to the manual switch. it can. When a failure occurs partially, the phase unit can be easily exchanged, which contributes to Reduce (reduction), Reuse (reuse), Repair (repair), and Recycle (recycle, reuse).
[0023]
Further, since the mechanism for operation is provided on the front side of the resin mold, the mechanism board 30 located on the front is grounded, so that no electric shock is received. Since the resin mold portion without the ground layer is located at a recessed position, there is no possibility of contact during normal work.
[0024]
In the above-described embodiment, specific configurations of the fixed electrode rod 14 and the movable electrode rod 24 of the single-pole molded contact portion B are described, but these configurations are not essential requirements of the present invention. Furthermore, although the upper and left edges 30b, 30c of the substantially square mechanism substrate 30 are bent, these configurations are not essential to the present invention. Further, the mounting bracket D is used to install the mold switch A in the power distribution supply box C, but the mounting bracket D is not an essential requirement of the present invention. Further, the mechanism for operating the interlocking shaft 32 and the like is not limited to the above embodiment.
[0025]
【The invention's effect】
According to the first and second aspects of the present invention, it is unnecessary to reduce the electric field of the metal body, the conductive paint, the shield, and the like to the box body of the single-pole mold contact portion and to make the ground fault priority structure. It has a narrow box structure, can be made thinner, has a smaller and simpler shape, can be easily pressurized and gelled, and can reduce mold costs and molding costs. As a result, while maintaining various characteristics, handling operability, operability, reliability, and the like required of the underground power distribution switch, it greatly contributes to a reduction in manufacturing cost.
[0026]
In addition, since a single-pole molded contact portion is independently attached to one grounded mechanism substrate for each phase, a complete ground fault priority structure is achieved. Furthermore, the opening area of the single-pole mold contact area and the opening area of the mechanism board are large, and they are connected to a three-phase integrated box, so that when current is interrupted, replacement with fresh air is performed smoothly. Load current switching frequency increases. Further, since the grounding layer is not applied to the single-pole molded contact portion, the corona level is high, and even if it is soiled or cracked, it does not easily develop into a ground fault.
[0027]
As described above, the molded switch of the present invention does not use a member such as a tulip contact, which has been conventionally increased in cost. Therefore, in addition to cost reduction, a closing lid is not used, so that when the switch is opened and closed, The operation sound is not loud, and there is no damage caused by the impact at the time of opening / closing operation.
As a result, various characteristics, handling workability, operability, reliability, and the like required by the underground distribution switch can be sufficiently maintained.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state in which a single-pole molded contact portion according to an embodiment of the present invention is attached to a mechanism board in a three-phase arrangement.
FIG. 2 is a perspective view of a box before mounting electrodes of a single-pole molded contact portion according to the embodiment of the present invention.
FIG. 3 is a longitudinal sectional view of a box body of a single-pole molded contact portion according to the embodiment of the present invention.
FIG. 4 is an explanatory view of a fixed electrode rod attached to a single-pole molded contact portion according to the embodiment of the present invention.
FIG. 5 is an explanatory diagram of a movable electrode rod attached to a single-pole molded contact portion according to the embodiment of the present invention.
FIG. 6 is a vertical cross-sectional view of the mold switch according to the embodiment of the present invention in an “OFF” state.
FIG. 7 is a front view of a mold switch according to the embodiment of the present invention.
FIG. 8 is a vertical cross-sectional view of the mold switch of the embodiment of the present invention in an “on” state.
FIG. 9 is an exploded perspective view showing a state in which the mold switch of the embodiment of the present invention is mounted on a mounting bracket.
FIG. 10 is a perspective view showing a state in which the mold switch of the embodiment of the present invention is mounted on a mounting bracket.
FIG. 11 is a front view of a state in which the mold switch of the embodiment of the present invention is installed in a power distribution supply box using a mounting bracket.
FIG. 12 is a side view of a mold disconnector using a conventional closing lid.
FIG. 13 is a front view of a state in which a mold disconnector using a conventional closing lid is installed in a power distribution supply box.
[Explanation of symbols]
Reference Signs List A Mold switch B Single-pole molded contact point 1 Box 2 Box opening 8 Upper bushing 9 Lower bushing 10 Upper terminal 13 Fixed blade electrode 14 Fixed electrode rod 15 Arc extinguishing chamber 16a Arc extinguishing chamber 20 Lower Terminal portion 23 Movable blade electrode 24 Movable electrode rod 26 Drive lever 32 Interlocking shaft 30 Mechanism board 30a Opening

Claims (2)

A box body is erected with the flat sides on the left and right sides, the front face of the box body is set as an opening surface, and through holes are formed in the upper and lower surfaces of the erected box body, and the two through holes of the box body are provided. A bushing of a certain length is provided on the outer surface portion of each to form an upper bushing portion and a lower bushing portion,
A terminal section is provided at one end, and a fixed blade electrode of a fixed electrode rod having a fixed blade electrode provided at the other end is provided over an arc-extinguishing chamber body having a narrow arc-extinguishing chamber. Install the terminal inside the upper bushing outside the box and the electrode inside the box,
A terminal portion is provided at one end, and a movable electrode rod that rotatably supports a substantially L-shaped movable blade electrode is provided at the other end, and the movable electrode rod is placed in a lower bushing portion outside the box body. The electrode portion is mounted inside the box body, and the one end of the insulating rod is rotatably supported at an end of the movable blade electrode that is not a movable contact,
The single-pole molded contact portions having these structures are arranged in a three-phase arrangement at a predetermined interval, and are aligned with the shape and position of the front opening surface of each of the boxes at the opening edges of the front of these boxes. Grounding and mounting a three-phase integrated mechanism board provided with an opening of approximately the same shape and size,
The other end of each of the three drive levers, one end of which is connected to the operating mechanism provided on the mechanism board, is inserted into each box from each opening of the mechanism board, and the other end of each of the insulating rods Pivotally supported,
By rotating the insulating rods by operating the operation mechanism, rotating the movable blade electrodes together, and attaching and detaching each movable blade electrode and each fixed blade electrode, the three poles are interlocked. An underwater molded switch for underground power distribution that opens and closes. Each of the boxes is not subjected to an electric field relaxation process, and a conductor is not inserted inside, each phase is formed of an insulating resin material alone, and each phase is separated to form three phases. Item 7. An underwater molded switch for underground power distribution according to item 1.

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