JPH08273716A - Concrete structure and grounding structure of apparatus installed in concrete structure - Google Patents

Abstract

PURPOSE: To provide a concrete structure in which the projection of a grounding conductor is eliminated and the raising curing of a floor is made unnecessary at the time of carry-in/out of apparatus. CONSTITUTION: A metal case 25 is leveled so as not to project from the surface, welded to a bar arrangement 9, then embedded in a concrete building frame 4. An embedding side ground terminal 20 is fixed to the metal case 25 with a case fixing nut 24. An embedding side grounding conductor 19 connected to a main mesh arranged in a lower ground of the concrete base body 4 is fixed to a compression terminal 22 of the embedding side ground terminal 20. After an apparatus is installed in a concrete structure, a terminal of a standing-up side grounding conductor connected to the apparatus is screwed to a bolt part 23 of the embedding side ground terminal 20 to ground the apparatus.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete structure in which heavy electric equipment such as gas-insulated electric equipment and transformers are installed in a substation and a grounding structure for the heavy electric equipment.

[0002]

2. Description of the Related Art Conventionally, electric power generated by a power plant is transmitted at a high voltage to a substation provided around an electric power consumption area such as an industrial area or an urban area, and is transformed into a low voltage at the substation. , Power is supplied to customers. Here, when constructing the substation, along with responding to social situations such as effective use of land, prevention of noise, and harmony with the surrounding environment such as appearance,
There is an active movement to construct substations with high performance in order to improve the reliability of electric power equipment itself, labor saving in maintenance and inspection, and improvement in safety and environmental resistance. Therefore,
GIS (gas-insulated substation: GAS) that uses sulfur hexafluoride (SF ₆ ) gas, which has excellent insulation performance, in place of the air-insulated substation that requires a vast site area that has been conventionally constructed INSULATED SUBSTATION) has been built. In such a GIS, as shown in FIGS. 9 and 10, a circuit breaker (CB), a disconnector (DS), a current transformer (CT), an instrument transformer (PT), a lightning arrester (LA), etc. A gas-insulated electrical device 1 in which each device constituting the substation is housed in a metal container and pressurized SF ₆ gas is sealed and hermetically sealed in the internal space is a concrete skeleton 4 constructed in the site 3. It is laid out in a complex and efficient manner on the top. Then, a large amount of electric power sent via a power transmission line (not shown) is received via the bushing 2 and is conducted to a transformer (not shown) via the gas-insulated electric device 1 laid out in a composite manner. Then, it is transformed into a predetermined electric power.

These gas-insulated electric devices 1 are electrically connected to each other by a bus bar in a pressure vessel which is filled with SF ₆ gas under pressure and hermetically sealed in its internal space, and between the vessels.
Since the flange portions of the container are tightly connected to each other by bolt connection, highly accurate positioning and leveling are required in the installation work. Further, since these gas-insulated electric devices 1 are large and heavy, they are required to have robustness at the installation site and further have earthquake resistance. Further, the equipment is required to be grounded so that the rise in the potential of the induction portion due to the ground fault of the gas-insulated electric equipment 1 does not pose a danger to the human body and the equipment.
Therefore, in the site 3, a concrete structure divided into blocks is installed for the installation of the gas insulated electric device 1. In this concrete structure, as shown in FIG. 11, embedded bases 5 made of a metal plate laid out so as to correspond to the pillars 1a of the gas-insulated electric device 1 are leveled while leaving exposed surfaces, Further, a grounding wire 6 is embedded in the concrete skeleton 4 so as to extend from the surface. And gas-insulated electrical equipment 1
As shown in FIG. 12, the adapter 1b fastened to the bottom of the pedestal 1a by the mounting bolts 1c is welded to the exposed surface of these embedded bases 5, and the ground wire 6 is connected to the adapter 1b for installation. ing.

Here, a conventional construction method for a concrete structure will be described with reference to FIG. First, a predetermined area in the site 3 is excavated, the main mesh 7 is laid, the ground wire 6 is electrically connected to the main mesh 7, and the leveled concrete 8 is poured. Then, the bar arrangement 9 and the differential bar 10 are laid, and the first concrete 11 is placed. Then, the reinforcing bar 9 is constructed, and the auxiliary mesh 12 is electrically connected to the grounding wire 6 and laid. Further, the L-shaped angle 13 is leveled and welded to the differential bar 10, and the embedded base 5 is leveled and welded and fixed to the L-shaped angle 13. Then, leaving the exposed surface of the embedded base 5 and
The second concrete 14 is placed so that the tip of the ground wire 6 extends from the surface in the vicinity of the embedded base 5, and the concrete structure is constructed. The main mesh 7 is made of a copper material and is spread so as to cover the lower part of the concrete skeleton 4 and is laid at a depth of 0.75 m or more underground to form a ground electrode. The ground wire 6 is a vinyl-coated electric wire (S: 100 m) made of a twisted copper wire.
m ² ) is used. Moreover, the concrete skeleton 4 is composed of the uniform concrete 8, the first concrete 11 and the second concrete 14.

In the concrete structure constructed by dividing the site 3 in this manner, the ground wire 6 is wound as shown in FIG. 14 so as not to obstruct traffic until the gas-insulated electric equipment 1 is installed. It is held in a broken state. Since the gas-insulated electric device 1 is a heavy object, it needs to be carried in by a large vehicle. When the vehicle travels on the concrete skeleton 4, the floor surface of the concrete skeleton 4 may be damaged, or the exposed portion of the ground wire 6 may be ridden to damage or deteriorate the ground wire 6. In addition, the exposed portion of the ground wire 6 may interfere with the work of loading the device. Therefore, a steel plate is laid on the concrete skeleton 4 so as to cover the exposed portion of the ground wire 6, and the floor surface is lifted and cured. After that, the vehicle is run on the steel plate and equipment such as the gas-insulated electric equipment 1 is carried in and laid out in a predetermined arrangement. At this time, the pedestal 1a of each device is placed on the embedded base 5. Therefore, the adapter 1b fastened to the bottom surface of the pedestal 1a by the mounting bolt 1c is welded to the embedded base 5, and the ground wire 6 is electrically connected to the pedestal 1a to complete the installation of the device. It goes without saying that the floor surface of the concrete skeleton 4 needs to be raised and cured even when the equipment is carried out.

[0006]

As described above, in the conventional concrete structure, the ground wire 6 extends from the concrete skeleton 4 and is buried therein. The equipment such as the gas-insulated electric equipment 1 installed in the concrete structure needs to be grounded, and since the concrete structure is constructed including the additional equipment, the number of grounding wires 6 is several hundred. Will also reach. Therefore, at the time of loading / unloading the equipment, in order to prevent damage to the floor surface of the concrete skeleton 4 and damage or deterioration of the ground wire 6 due to traveling of the vehicle, a steel plate is spread so as to cover the exposed portion of the ground wire 6. There is a problem that the floor surface raising and curing are required, a lot of labor is required, the construction cost is increased, and the construction period is prolonged.
In addition, since the grounding wire 6 is laid including the additional equipment, the exposed portion of the grounding wire 6 becomes a hindrance to equipment loading / unloading work or equipment installation / removal work.

The present invention has been made in order to solve the above problems, and the grounding wire is buried so as not to extend from the surface to eliminate the protruding portion from the surface of the concrete skeleton, so that the equipment can be carried in / out. It is possible to eliminate the need for floor raising and curing when unloading, as well as equipment loading / unloading work and installation / installation /
The purpose is to obtain a concrete structure and a grounding structure for equipment that facilitate removal work.

[0008]

A concrete structure according to a first aspect of the present invention is a concrete structure installed on a site, a grounding electrode laid on the ground below the concrete structure, and a concrete structure. A metal case having an upper surface that is embedded so as not to project to the surface side of the opening, a flange portion, a buried-side cable connection portion provided on one side of the flange portion, and a buried portion provided on the other side of the flange portion. An embedded side ground terminal having a side connection terminal portion, the flange portion being fixed to the bottom surface of the metal case so that the embedded side connection terminal portion is located inside the metal case, and a ground electrode and an embedded side cable at both ends, respectively. And a buried side grounding wire electrically connected to the connecting portion and buried in the concrete skeleton.

A concrete structure according to a second aspect of the present invention is the concrete structure according to the first aspect, wherein a threaded portion is formed in the buried-side connection terminal portion.

Further, the concrete structure according to a third aspect of the present invention is the concrete structure according to the first aspect, wherein the buried side cable connecting portion is composed of a compression terminal, and the other end of the buried side ground wire is crimped to the compression terminal. It is fixed.

Further, the grounding structure of the equipment installed on the concrete structure according to the fourth aspect of the present invention is a concrete structure installed on the site and a grounding electrode laid on the ground below the concrete structure. And a metal case having an opening on the upper surface that is embedded so as not to project to the surface side of the concrete skeleton, a flange portion, an embedded cable connection portion provided on one side of the flange portion, and the other side of the flange portion. An embedded grounding terminal having an embedded connecting terminal portion provided with the flange portion fixed to the bottom surface of the metal case so that the embedded connecting terminal portion is located inside the metal case, and both ends are ground electrodes. And a concrete structure composed of a buried-side grounding wire electrically connected to the buried-side cable connection part and buried in the concrete skeleton, and installed on the concrete structure. A rising side having an attached device, a rising side connecting terminal portion and a rising side cable connecting portion, the rising side connecting terminal portion being electrically connected to the buried side connecting terminal portion and being attached to the buried side ground terminal. A ground terminal and a rising ground wire, both ends of which are electrically connected to the equipment and the rising cable connecting portion, respectively.

A grounding structure for an apparatus installed on a concrete structure according to a fifth aspect of the present invention is the same as the fourth aspect of the present invention, except that one of the buried side connecting terminal portion and the rising side connecting terminal portion has a male screw portion. However, a female screw portion is formed on the other side, and the rising side connection terminal portion is electrically connected to the embedded side connection terminal portion by screwing the male screw portion and the female screw portion.

Further, the grounding structure of the equipment installed in the concrete structure according to the sixth aspect of the present invention is the same as the fifth aspect, wherein the detent pin has the embedded side connecting terminal portion and the embedded side connecting terminal portion. One of the upright side connection terminal portions screwed to is penetrated and driven into the other.

Further, a grounding structure for equipment installed in a concrete structure according to a seventh aspect of the present invention is the same as the fourth aspect, wherein the buried side connecting terminal portion and the rising side connecting terminal portion have flat portions respectively. The rising side connection terminal portion is electrically connected to the embedded side connection terminal portion by forming the flat portions so as to be in close contact with each other and fastening the fastening member.

Further, the grounding structure of the equipment installed in the concrete structure according to the eighth aspect of the present invention is the same as the fourth aspect, wherein the buried side cable connecting portion and the rising side cable connecting portion are compression terminals. The buried side grounding wire and the rising side grounding wire are crimped and fixed to the respective compression terminals.

[0016]

In the first aspect of the present invention, since the grounding wire does not project from the concrete skeleton, the operator does not trip and the grounding wire is not damaged by traveling of the vehicle. When the equipment is loaded or unloaded, a plywood board is laid on the concrete skeleton to prevent the surface of the concrete skeleton from being damaged due to the running of the vehicle, and the floor-raising / curing using steel plates is not required.

In the second invention of the present invention,
Since the threaded part is formed on the embedded side connection terminal part, if the threaded part is formed on the connection terminal part of the ground wire on the device side installed in the concrete structure, the device can be easily screwed together. Grounded. Then, the contact area of the connecting portion between the two becomes large, the contact resistance at the connecting portion can be made extremely small, and the size can be reduced.

In the third invention of the present invention,
Since the buried-side cable connection portion is composed of the compression terminal and the buried-side ground wire is crimped and fixed to the compression terminal, an increase in contact resistance with time in the connection portion can be suppressed.

In the fourth invention of the present invention,
Since the ground wire of the equipment is divided into the buried ground wire and the rising ground wire, the equipment is grounded using the rising ground wire after being installed on the concrete structure. Therefore,
Since the grounding wire does not protrude from the concrete structure, workers will not trip and the grounding wire will not be damaged by the traveling of the vehicle.When loading or unloading equipment, spread the plywood board on the concrete structure. It is possible to prevent damage to the surface of the concrete skeleton due to the running of the vehicle, and it is not necessary to cure the floor with a steel plate. Further, the rising ground wire can be procured according to the wiring length from the device side to the buried ground terminal, and the waste of the ground wire can be eliminated. Further, there is no protrusion of the grounding wire for the additional equipment, which does not interfere with the worker or the vehicle.

In the fifth aspect of the present invention,
Since the male screw portion is formed on one of the embedded side connection terminal portion and the rising side connection terminal portion and the female screw portion is formed on the other side, the rising side ground terminal can be easily attached to and detached from the embedded side ground terminal. Further, since the connection is made by screwing the screw portion, the contact area is increased, the contact resistance at the connection portion is reduced, and the connection portion can be downsized.

In the sixth aspect of the present invention,
Since the anti-rotation pin is driven into the embedded side connection terminal part and the rising side connection terminal part, there is no decrease in screwing force due to loosening of the screw part, no decrease in contact surface pressure, and stable grounding of equipment for a long time. Done.

In the seventh aspect of the present invention,
Since the flat surface portion is formed on each of the buried side connection terminal portion and the rising side connection terminal portion and the flat surface portions are brought into close contact with each other and tightened by the fastening member, the buried side grounding of the rising side ground terminal is performed. It can be easily attached to and detached from the terminal.

In the eighth aspect of the present invention,
The buried-side cable connecting portion and the rising-side cable connecting portion are each composed of a compression terminal, and the buried-side grounding wire and the rising-side grounding wire are crimped and fixed to each of the compression terminals. Is suppressed and the equipment is grounded stably over the long term.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. Example 1. 1 is a sectional view showing a main part of a concrete structure showing a first embodiment of the present invention, and FIG. 2 is an exploded sectional view showing a buried side ground terminal in a concrete structure according to the first embodiment of the present invention. In FIG. 9, the same or corresponding parts as those of the conventional concrete structure shown in FIGS. 9 to 13 are designated by the same reference numerals, and the description thereof will be omitted. In the figure,
Reference numeral 19 is a buried side ground wire which is constructed similarly to the conventional ground wire 6 and has one end electrically connected to the main mesh 7, and 20 is a buried side ground terminal made of a copper material. Reference numeral 20 denotes a nut portion 21 as a flange portion, a hollow compression terminal 22 as a buried side cable connecting portion extending to one side of the nut portion 21, and a buried side connecting terminal extending to the other side of the nut portion 21. The bolt portion 23 as a portion is integrally formed and configured. 24 is the ground terminal 20 on the buried side
The case fixing nut 25 is screwed to the bolt portion 23, and 25 is a box-shaped metal case having an attachment hole 25a formed in the bottom surface and an opening on the upper surface side. Reference numeral 26 denotes a protective cap. The protective cap 26 has a hollow guide portion 26a which can accommodate the bolt portion 23 and is provided upright from the bottom surface.

Construction of the concrete structure according to the first embodiment will now be described. Prior to the construction of the concrete structure, the bolt portion 23 is inserted from the outside into the mounting hole 25a of the metal case 25, the case fixing nut 24 is screwed from the inside to the bolt portion 23, and the case fixing nut 24 is tightened, Embedded side ground terminal 2 in metal case 25
Stick 0 and keep it as one piece. Therefore, a predetermined area in the site 3 is excavated, the main mesh 7 is laid, the buried side ground wire 19 is electrically connected to the main mesh 7, and the leveled concrete 8 is placed. Then, the bar arrangement 9 and the differential bar 10 are laid, and the first concrete 11 is placed. Then,
Construction of bar arrangement 9 and auxiliary mesh 12 to buried side ground wire 19
It is electrically connected to and laid. Further, the L-shaped angle 13 is leveled and welded to the differential bar 10, and the embedded base 5 is leveled and welded and fixed to the L-shaped angle 13. Next, the other end of the buried side ground wire 19 is connected to the compression terminal 22.
Insert it inside and use the crimping jig (not shown) to compress terminal 2
2 is deformed under pressure, and the buried side ground wire 19 is compressed into a compression terminal 22.
Crimped and fixed to. Then, the buried side ground terminal 20 is attached to the bar arrangement 9.
The metal case 25 integrated with is leveled and fixed by welding. After that, the second concrete 14 is poured so that the exposed surface of the embedded base 5 is left and the upper surface of the metal case 25 is in the surface position. Further, the protection cap 26 is attached to the metal case 25 from above so that the bolt portion 23 is inserted into the guide 26a, and the concrete structure is constructed.

In the concrete structure thus constructed, the surface positions of the concrete skeleton 4, the metal case 25 and the protective cap 26 are substantially the same. Therefore, when installing the gas-insulated electrical equipment 1, when installing the concrete frame 4
A veneer board is laid over, a vehicle is run on the veneer board, equipment such as the gas-insulated electric equipment 1 is carried in, and laid out in a predetermined arrangement. Then, the adapter 1b fastened to the bottom surface of the pedestal 1a placed on the embedded base 5 with the mounting bolt 1c is welded to the embedded base 5. Further, grounding work of each device described later is performed, and installation of the device is completed.

Next, the grounding work of the equipment will be described with reference to FIGS. 3 and 4. The rising ground terminal 27 is made of a copper material, and has a rising nut 28 as a rising connection terminal portion and a hollow compression terminal 2 as a rising cable connection portion.
9 and 9 are integrally formed. Then, the rising nut 28 is internally threaded with the bolt portion 23.
a is threaded. Therefore, one end side of the rising ground wire 30 is inserted into the compression terminal 29 of the rising ground terminal 27, and the compression terminal 29 is deformed under pressure by using a crimping jig (not shown). 30 is crimped and fixed to the compression terminal 29. After that, the protective cap 26 is removed and the bolt 2
The packing 31 is fitted into the screw 3, and the female screw portion 28 a is screwed into the bolt portion 23. Then, the rising-side nut 28 is rotated by using the tightening spanner 34 to fix the rising-side ground terminal 27 to the embedded-side ground terminal 20 by tightening. Then, a hole is formed that penetrates the rising nut 28 and the bolt portion 23 obliquely from the upper side to the lower side, and the detent pin 32 made of an iron material or a stainless material is inserted and driven. Then, in order to eliminate the depressions on the surface of the concrete skeleton 4 and to prevent water from entering the metal case 25, caulking material 33 is filled in the metal case 25, and the other end of the upside grounding wire 30 is grounded. Electrically connected to the pillar 1a to complete the grounding work of the device.

According to the first embodiment, since the ground wire does not project from the surface of the concrete skeleton 4, it is only necessary to prevent damage to the concrete skeleton 4 when the vehicle for loading / unloading equipment is run. Of course, a plywood board that is lighter and cheaper than a steel board may be laid on the concrete skeleton 4. Therefore, unlike the conventional case, it is not necessary to cure the floor surface by using a steel plate, and the equipment loading / unloading work can be simplified.
Moreover, it can be implemented in a short period of time, and the construction period can be shortened and the construction cost can be reduced. Further, even if the buried side ground terminal 20 is installed including the additional equipment, it is not exposed from the concrete skeleton 4 and does not interfere with the operator or get caught and fall, and the equipment can be carried in / out. It is possible to improve workability and safety of carry-out work or equipment installation / removal work. Further, the ground wire is divided into the buried ground wire 19 and the rising ground wire 30, and the rising ground wire 30 is attached after the equipment is installed. Therefore, the rising ground wire 30 suitable for the wiring length is prepared. It is possible to eliminate waste of the ground wire.

Further, the buried side ground terminal 20 has a bolt portion 23.
And a rising nut 28 is provided on the rising ground terminal 27, and a female screw portion 28a is threaded on the rising nut 28. Therefore, by screwing the female screw portion 28a onto the bolt portion 23, the rising ground is formed. Terminal 27 is buried side ground terminal 2
Can be attached to 0. Therefore, the rising ground terminal 2
7 can be easily attached and detached, and equipment installation and removal can be easily performed. Also, the contact area between the connecting portions can be increased by screwing the screws together, the contact resistance can be made extremely small, and the embedded grounding terminal 20 and the rising grounding terminal 27 can be downsized, and an increase in grounding resistance can be suppressed. it can. Further, since the buried side ground terminal 20 is fastened and fixed to the metal case 25 using the case locking nut 24, when the rising side ground terminal 27 is mounted, co-rotation of the buried side ground terminal 20 is prevented. Stable tightening strength can be obtained. Further, since the rotation stopping pin 32 is driven in, even if the rising side ground wire 30 is twisted, the rotation of the rising side ground terminal 27 in the direction of weakening the fastening force is prevented, and the bolt portion 23 and the rising side grounding terminal 27 are prevented. Female thread portion 28a of the nut 28
The reduction of the contact surface pressure with is prevented. Therefore, it is possible to suppress an increase in contact resistance with time in the connection portion, and perform stable grounding of the device for a long period of time. In addition, the buried side ground wire 19
Since the rising ground wire 30 is crimped and fixed to the compression terminals 22 and 29, the contact resistance of the connecting portion is prevented from increasing with time, and the equipment is grounded stably for a long period of time. Further, since the packing 31 is interposed when the rising nut 28 is screwed to the bolt portion 23, intrusion of water or the like into the rising nut 28 is prevented, and the bolt portion 23 and the female screw portion 28a are Corrosion of the contact portion is suppressed, increase in contact resistance with time of the connection portion is suppressed, and stable grounding of the device is performed for a long period of time.

In the first embodiment, the buried side ground terminal 20 is formed with the bolt portion 23 which is the male screw portion and the rising side ground terminal 27 is formed with the female screw portion 28a. Even if the female screw portion is formed on the upper side and the male screw portion is formed on the rising side ground terminal 27, the same effect is obtained.

Embodiment 2 FIG. 5 is a partially broken perspective view showing a buried side grounding terminal in a concrete structure according to a second embodiment of the present invention, and FIG. 6 is a grounding structure of equipment installed in the concrete structure according to a second embodiment of the present invention. It is a perspective view showing a rising ground terminal. In the figure, 40
Is a buried side ground terminal made of a copper material, and the buried side ground terminal 40 is a flange portion 41, a hollow compression terminal 42 extending to one side of the flange 41, and a hollow compression terminal 42 and a flange. The flat plate portion 43 as an embedded side connection terminal portion extended to the other side of the portion 41 is integrally formed. Reference numeral 44 is a rising-side ground terminal made of a copper material, and the rising-side ground terminal 44 is formed by integrally forming a flat plate portion 45 and a hollow compression terminal 46 as a rising-side connection terminal portion. The other structure is the same as that of the first embodiment.

In the second embodiment, as shown in FIG. 7, the mounting side ground terminal 40 is attached to the metal case 25 through the mounting hole 40a formed in the flange portion 41.
It is fastened and fixed by a and a nut 47b. Then, the flat plate portion 45 of the upright grounding terminal 44 is brought into close contact with the flat plate portion 43 of the buried side ground terminal 40, and as a fastening member via the mounting holes 43a and 45a formed in the flat plate portions 43 and 45. It is fastened and fixed by the mounting bolt 48a and the nut 48b. Further, the buried side ground wire 19 and the upright ground wire 30 are crimped and fixed to the compression terminals 42 and 46, respectively.

Therefore, also in the second embodiment, the same effect as that of the first embodiment can be obtained. In this case, the buried-side ground terminal 40 and the rising-side ground terminal 44 are connected to the flat plate portions 43, 4
Since the planar portions of No. 5 are connected by surface contact with each other, the contact area of the connecting portion cannot be increased and the size becomes larger than that in the first embodiment.

Example 3. FIG. 8 is a cross-sectional view of essential parts showing a connection structure of equipment installed in a concrete structure according to Embodiment 3 of the present invention. In the figure, 49 is a flange part made of a copper material, and this flange part 49 is a main flange part 49a for attaching to the metal case 25 and a sub-flange part projectingly provided on both sides of this main flange part 49a. It is composed of 49b and 49c. 5
Reference numeral 0 denotes a hollow compression terminal 50 made of a copper material as a buried side cable connection portion, and a flat plate portion 50a is formed on one side of the compression terminal 50. Here, the flange portion 4
9 to the sub-flange portion 49b of the flat plate portion 50b mounting bolt 4
8a and nuts 48b are tightened and fixed, and the flange 4
9 and the compression terminal 50 are integrated to form a buried side ground terminal. Then, the main flange portion 49a is fastened and fixed to the metal case 25 with the mounting bolt 47a and the nut 47b, and the buried side ground terminal is mounted. Further, the flat plate portion 45 is attached to the sub-flange 49c by the mounting bolt 48a.
The upright contact terminal 44 is attached to the buried side ground terminal by fastening and fixing with the nut 48b. The sub-flange portion 49c corresponds to the buried-side connection terminal portion.

According to the third embodiment configured as described above,
The buried-side contact terminals are attached to the flange portion 49 and the compression terminal 50.
The configuration is the same as that of the above-described second embodiment except that it is divided, and the same effect as that of the above-described second embodiment is obtained.

[0036]

Since the present invention is constituted as described above, it has the following effects.

According to the first aspect of the present invention, the concrete skeleton installed on the site, the grounding electrode laid on the ground below the concrete skeleton, and the concrete skeleton embedded so as not to project to the surface side of the concrete skeleton. A metal case having an open upper surface, a flange portion, an embedded cable connecting portion provided on one side of the flange portion, and an embedded side connecting terminal portion provided on the other side of the flange portion, A buried side ground terminal having the flange portion fixed to the bottom surface of the metal case so that the buried side connection terminal portion is located in the metal case, and both ends thereof are electrically connected to the ground electrode and the buried side cable connection portion, respectively. Since the grounding wire is embedded in the concrete skeleton, the grounding wire does not project from the concrete skeleton, making it easy to carry in / out equipment and install / remove equipment. Cleat structure is obtained. Furthermore, when carrying in / out the equipment, it is not necessary to cure the floor by raising the surface of the floor by using a steel plate, and a concrete structure capable of shortening the construction period and reducing the construction cost can be obtained.

According to a second aspect of the present invention, in the first aspect of the invention, the embedded connecting terminals are provided with the threaded portions, so that the grounding work of the equipment installed on the concrete structure can be performed. It can be done easily.

Further, according to a third aspect of the present invention, in the first aspect of the invention, the buried side cable connecting portion is composed of a compression terminal, and the other end of the buried side ground wire is crimped and fixed to the compression terminal. Therefore, the increase in contact resistance with time in the connection portion can be suppressed to an extremely small value.

Further, according to the fourth aspect of the present invention, the concrete skeleton installed on the site, the grounding electrode laid on the ground below the concrete skeleton, and the surface of the concrete skeleton do not protrude. A metal case having an upper surface embedded in the opening, a flange portion, an embedded cable connecting portion provided on one side of the flange portion, and an embedded side connection terminal portion provided on the other side of the flange portion. A buried-side ground terminal having the flange portion fixed to the bottom surface of the metal case so that the buried-side connection terminal portion is located in the metal case;
A concrete structure composed of a buried side ground wire that is electrically connected to the ground electrode and the buried side cable connection part and buried in the concrete frame, and a device installed on the concrete structure, A rising side grounding terminal having an upper side connecting terminal part and a rising side cable connecting part, the rising side connecting terminal part being electrically connected to the buried side connecting terminal part and attached to the buried side grounding terminal, and both ends respectively. Since the equipment and the rising-side ground wire electrically connected to the rising-side cable connection portion are provided, the ground wire is divided into the buried-side ground wire and the rising-side ground wire, and waste of the ground wire can be suppressed. A grounding structure for equipment installed in a concrete structure can be obtained.

According to a fifth aspect of the present invention, in the fourth aspect, a male screw portion is formed on one of the embedded side connecting terminal portion and the rising side connecting terminal portion, and a female screw portion is formed on the other side. Since the rising-side connecting terminal portion is electrically connected to the embedded-side connecting terminal portion by screwing the male screw portion and the female screw portion, grounding work can be easily performed. Further, the contact area of the connecting portion can be made large, the contact resistance can be made extremely small, the device can be grounded well, and the buried side grounding terminal and the rising side grounding terminal can be downsized.

Further, according to a sixth aspect of the present invention, in the above-mentioned fifth aspect, the whirl-stop pin is screwed to the embedded side connection terminal portion and the embedded side connection terminal portion. Since it penetrates through one side and is driven into the other side, an increase in contact resistance with time in the connecting portion is suppressed, and stable grounding of the device is performed for a long period of time.

According to a seventh aspect of the present invention, in the above-mentioned fourth aspect, the embedded side connecting terminal portion and the rising side connecting terminal portion are each provided with a flat surface portion, and the flat surface portions are closely contacted to each other. Since the rising-side connecting terminal portion is electrically connected to the buried-side connecting terminal portion by fastening the fastening member, the grounding work can be easily performed.

According to an eighth aspect of the present invention, in the above-mentioned fourth aspect, the buried side cable connecting portion and the rising side cable connecting portion are each constituted by a compression terminal, and the buried side grounding wire and the rising side grounding are provided. Since the wire is crimped and fixed to each of the compression terminals, an increase in contact resistance with time in the connection portion is suppressed, and stable grounding of the device is performed for a long period of time.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of a concrete structure according to a first embodiment of the present invention.

FIG. 2 is an exploded cross-sectional view showing a buried side ground terminal in the concrete structure according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of essential parts showing a grounding structure of an apparatus installed in a concrete structure according to Example 1 of the present invention.

FIG. 4 is a perspective view showing a grounding jig of the equipment installed in the concrete structure according to the first embodiment of the present invention.

FIG. 5 is a partially cutaway perspective view showing a buried-side ground terminal in a concrete structure according to a second embodiment of the present invention.

FIG. 6 is a perspective view showing a rising-side grounding terminal in a grounding structure of a device installed in a concrete structure according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view of essential parts showing a grounding structure of a device installed in a concrete structure according to Example 2 of the present invention.

FIG. 8 is a cross-sectional view of essential parts showing a grounding structure of a device installed in a concrete structure according to Embodiment 3 of the present invention.

FIG. 9 is a plan view showing an example of a layout of gas-insulated electric equipment in a substation.

10 is a cross-sectional view taken along the line XX of FIG.

FIG. 11 is a plan view showing an example of a concrete structure installed on the premises of a substation.

FIG. 12 is a perspective view of a main part showing a grounding structure of a device installed in a conventional concrete structure.

FIG. 13 is a sectional view of an essential part showing a conventional concrete structure.

FIG. 14 is a plan view of an essential part showing a conventional concrete structure.

[Explanation of symbols]

1 gas-insulated electrical equipment (equipment), 3 sites, 4 concrete frame, 7 main mesh (ground electrode), 19 buried side ground wire, 20 buried side ground terminal, 21 nut part (flange part), 22 compression terminal (buried side) Cable connection),
23 bolt part (buried side connection terminal part), 25 metal case, 27 rising upper side ground terminal, 28 rising side nut (standing side connection terminal part), 28a female screw part, 29 compression terminal (upstanding side cable connection part), 30 standing Upper ground wire, 32
Non-rotating pin, 40 buried side ground terminal, 41 flange part, 42 compression terminal (buried side cable connection part), 43
Flat plate portion (buried side connection terminal portion), 44 rising side ground terminal, 45 flat plate portion (upper side connecting terminal portion), 46 compression terminal (upper side cable connecting portion), 48a mounting bolt (fastening member), 48b nut ( Fastening member), 49 flange part, 49c Sub-flange part (buried side connection terminal part), 5
0 Compressed terminal (buried side cable connection part).

Claims (8)

[Claims] 1. A concrete skeleton installed on the premises, a ground electrode laid on the ground below the concrete skeleton, and a metal having an opening on the upper surface embedded so as not to project to the surface side of the concrete skeleton. A case, a flange portion, an embedded-side cable connection portion provided on one side of the flange portion, and an embedded-side connection terminal portion provided on the other side of the flange portion, wherein the embedded-side connection terminal portion is the metal. A buried side ground terminal having the flange portion fixed to the bottom surface of the metal case so as to be located in the case, and both ends thereof are electrically connected to the ground electrode and the buried side cable connecting portion, respectively, to the concrete frame. A concrete structure comprising a buried grounding wire on the buried side. 2. The concrete structure according to claim 1, wherein a threaded portion is formed on the buried side connection terminal portion. 3. The concrete structure according to claim 1, wherein the buried side cable connecting portion is composed of a compression terminal, and the other end of the buried side ground wire is crimped and fixed to the compression terminal. 4. A concrete skeleton installed on the site, a grounding electrode laid on the ground below the concrete skeleton, and a metal having an upper surface embedded so as not to project to the surface side of the concrete skeleton. A case, a flange portion, an embedded-side cable connection portion provided on one side of the flange portion, and an embedded-side connection terminal portion provided on the other side of the flange portion, wherein the embedded-side connection terminal portion is the metal. A buried side ground terminal having the flange portion fixed to the bottom surface of the metal case so as to be located in the case, and both ends thereof are electrically connected to the ground electrode and the buried side cable connecting portion, respectively, to the concrete frame. A concrete structure composed of a buried grounding wire, a device installed on the concrete structure, a rising side connecting terminal portion and a rising side cable. It has a connecting portion,
A rising side grounding terminal in which the rising side connecting terminal portion is electrically connected to the buried side connecting terminal portion and is attached to the buried side grounding terminal, and both ends are electrically connected to the device and the rising side cable connecting portion, respectively. A grounding structure for a device installed in a concrete structure, comprising: an upright grounding wire connected to. 5. A male screw portion is formed on one of the embedded side connecting terminal portion and the rising side connecting terminal portion, and a female screw portion is formed on the other side, and the rising side connecting terminal portion is screwed to the male screw portion and the female screw portion. Is electrically connected to the buried-side connection terminal portion, and the grounding structure for the equipment installed in the concrete structure according to claim 4. 6. The anti-rotation pin penetrates one of the embedded-side connecting terminal portion and the rising-side connecting terminal portion screwed to the embedded-side connecting terminal portion and is driven into the other. Item 5. A grounding structure for equipment installed in the concrete structure according to item 5. 7. The buried-side connecting terminal portion and the rising-side connecting terminal portion are each formed with a flat surface portion, and the flat-surface portions are brought into close contact with each other and the fastening member is fastened so that the rising-side connecting terminal portion is brought into contact. The grounding structure for a device installed in a concrete structure according to claim 4, wherein the grounding structure is electrically connected to the buried-side connection terminal portion. 8. The buried-side cable connecting portion and the rising-side cable connecting portion are each configured by a compression terminal, and the buried-side ground wire and the rising-side ground wire are crimped and fixed to each of the compression terminals. A grounding structure for a device installed on the concrete structure according to claim 4.