JPH04355620A - Optical fiber cable terminal device - Google Patents

Abstract

PURPOSE:To prevent damage due to a high potential difference by setting the same potential to a charger of an optical fiber cable terminal and a voltage applying conductor therebetween by a bridging conductor, and retracting a nonmetallic optical fiber cable along the bridging conductor. CONSTITUTION:In an optical fiber cable terminal 1, its charger such as an upper fitting is bridged to a vertical bus B1 of a voltage applying conductor B by a bridging conductor 30 of a steel reinforced aluminum cable, and the charger is set to the same potential as that of the conductor B. That is, one end of the conductor 30 is connected to the conductor B by a connecting fitting 28, and the other end of the conductor 30 is connected to an upper fitting of the cable 1 by a connecting fitting 29. A protective tube L3 in which an optical fiber cable A is inserted, is arranged along the conductor 30 set to the same potential as that of the conductor B, and secured by a grasp fixing fitting N. Thus, damage of the conductor 30 due to a high voltage of the nonmetallic cable A.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal device for pulling in an optical fiber cable that is wrapped around or attached to an energized conductor such as an overhead power transmission line or distribution line.

0002

[Prior Art] As shown in FIG. 5, the termination of an optical power transmission line constituted by a wrapped type OPGW in which an optical fiber cable is wound around a energized conductor such as an overhead power transmission line or a distribution line is a non-metallic optical fiber cable. A energized conductor B such as a power transmission line wrapped with A is connected to the jumper part B1 between the retaining clamp E of the retaining insulator D and the clamp G of the suspension insulator F in the substation retaining steel structure C, and between this clamp G and the ground. The retaining insulator H is lowered to near the ground by the vertical bus section B2 held in place by the clamp J, and introduced D from this clamp J to the cable head K on the ground, and the optical fiber cable A is separated from the energized conductor B. It is installed in optical fiber cable terminal Q.

The above-mentioned optical fiber cable terminal Q is constructed by passing an optical fiber cable A into an insulating sleeve a, filling it with an insulating mixture b, and airtightly closing the upper and lower openings with lids c, and fixing metal fittings d. Fix the optical fiber cable A with
The optical fiber cable A is configured to prevent water from penetrating into the surface of the optical fiber cable A.

0004

[Problem to be solved by the invention] The above-mentioned winding type OPGW
A signal is carried at the end or in the middle of the optical transmission line, and the transmission equipment that receives this signal is installed on the ground or on the ground side of a support. When introducing it into a transmission device on the ground side, it must be sufficiently insulated. Even if the optical fiber cable itself is an insulator, perfect insulation cannot always be expected under outdoor natural conditions due to contamination on the cable surface, and for this reason, the optical fiber cable wrapped around the energized conductor cannot be used for transmission on the ground side. It is not easy to provide sufficient insulation before introducing the fiber into the device, and there is a risk that the optical fiber cable at the introduction portion will be damaged by a high potential difference between the energized conductor and the ground.

[0005] Furthermore, in the optical fiber cable terminal described above, when the insulating mixture filled in the sleeve expands and contracts due to temperature changes, a void is created within the sleeve, and the electric field is locally concentrated in this void. There is a risk that the optical fiber cable located in this gap will be damaged.

The present invention solves the above-mentioned problems and converts non-metallic optical fiber cables wrapped around or attached to energized conductors such as overhead power transmission lines or distribution lines into optical fiber cable terminals without applying a high potential difference. It is an object of the present invention to provide an optical fiber cable pulling device which can be pulled into a terminal sleeve without creating a gap in the terminal sleeve.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the optical fiber cable terminal device of the present invention has the following features:
1) The live part of the optical fiber cable terminal 1 installed on the ground side to draw in the non-metallic optical fiber cable A that is wrapped around or attached to a energized conductor B such as an overhead power transmission line or distribution line, and the energized part of the optical fiber cable terminal 1. The conductor B is bridged with a bridging conductor 30 or 31, 32 to have the same potential, and the non-metallic optical fiber cable portion to be drawn into the optical fiber cable terminal 1 is wound or attached to this bridging conductor. It is designed to draw in

(2) The above-mentioned optical fiber cable terminal 1 is provided with a reservoir 5 at the upper end of the sleeve, and the insulating mixture 25 filled in the sleeve 2 is inserted into the reservoir 5 so that the upper surface thereof exceeds the upper end of the sleeve. It has a structure in which it is filled so that it can fit inside.

[0009]

[Operation] By providing a bridging conductor between the live part of the upper metal portion of the optical fiber cable terminal 1 and the energized conductor B, the live part of the optical fiber cable terminal becomes at the same potential as the energized conductor B. By wrapping the lead-in part of the non-metallic optical fiber cable that is led into the optical fiber cable terminal 1 around or along this bridging conductor, even if the surface of the non-metallic optical fiber cable A is contaminated, the lead-in part can be Since there is no high potential difference between the energized conductor and the ground, there is no risk of damage.

[0010] Furthermore, the reservoir 5 provided at the upper end of the cannula prevents the formation of voids within the cannula 2. The insulating mixture 25 expands and contracts due to temperature changes, and its upper surface moves up and down. Therefore, when the upper surface of the insulating mixture 25 is inside the sleeve 2, a gap is created above the upper surface of the insulation mixture inside the sleeve 2. However, since the upper surface of the insulating compound 25 is inside the reservoir 5 beyond the inside of the sleeve 2, no void is created within the sleeve 2, and therefore, damage to the optical fiber cable due to local electric field concentration in the void is prevented. Does not occur.

[0011]

[Embodiments] Examples of the present invention will be explained below with reference to the drawings. FIG. 1 shows an embodiment of an optical fiber cable terminal according to the present invention, and 1 indicates an optical fiber cable terminal,
2 is a sleeve made of porcelain, plastic, or rubber; 3 is a through gap in the sleeve 1; and 4 is a metal ring fixed to the outer periphery of the upper end of the sleeve.

A reservoir 5 is provided on the upper opening of the cannula 2.
is fixed to the metal ring 4 with screws 6. This reservoir 5 has a cylindrical portion 9 integrally provided on a bottom portion 8 having a center hole 7, and a lid portion 12 having a center hole 11 is attached to a flange portion 10 on the upper edge of the cylindrical portion 9 with screws 13. to form a reservoir space 14 inside, and the insulating mixture 25 filled in the through gap 3 of the cannula 2 is passed from the center hole 7 of the bottom 8 of the reservoir 5 with its upper surface beyond the upper end opening of the cannula. It is filled as indicated by 25' until it enters the reservoir space 14.

The center hole 11 of the lid portion 12 of the reservoir 5
The non-metallic optical fiber cable A is inserted into the cannula 1 through the center hole 7 of the bottom part 8 and fixed with the optical fiber cable fixing fitting 15 on the top surface of the lid part 12, and the fitting 15 is filled with waterproof compound 16. Airtight and waterproof. Further, an optical fiber cable fixing clamp 17 is provided on the lower surface of the bottom portion 8 to fix the optical fiber cable A. Reference numeral 18 denotes an O-ring for an oil seal that airtightly closes the joint surfaces of each part. Reference numeral 19 denotes a metal ring fixed to the outer periphery of the lower end of the sleeve 2, and a bottom plate 20 is fixed to the lower end of the sleeve with screws 21. The optical fiber cable A is inserted into the center hole 22 of the bottom plate 20 and fixed with a fixing fitting 23 on the lower surface of the bottom plate 20. 24 is a waterproof compound that is airtightly filled in the fixture 23. 27 is a pedestal, and the optical fiber cable terminal 1 is installed on the pedestal 27 with bolts 26. The optical fiber cable A inserted into the sleeve 2 through the center hole 11 of the lid 12 is brought out downward from the center hole 22 of the bottom plate 20, and the through gap 3 of the sleeve 2 is filled with an insulating mixture 25. Fill the reservoir space 14 until its upper surface passes from the upper end of the cavity 3 to the center hole 7 of the bottom 8 of the reservoir 5 and enters the reservoir space 14 as indicated by 25'.

Insulating mixture 25 filled in the sleeve 2
The upper surface of the mixture rises and falls as the temperature changes due to the difference in thermal expansion coefficient between the mixture itself and the cannula, and when the upper surface falls below the upper end of the cannula 2, the upper surface of the mixture in the cannula 2 rises. A gap is created, and an electric field is locally concentrated in this gap, damaging the optical fiber cable in the gap. However, as described above, the upper surface of the insulating mixture 25 exceeds the inside of the sleeve 2 and enters the reservoir 5. 25', the upper surface of the insulating mixture 25' remains in the reservoir space 1 even when the temperature changes.
Since it only moves up and down within the cannula 4 and does not descend into the cannula 2, no voids are created in the cannula 2. Therefore, since no local electric field concentration occurs due to the air gap, no dielectric breakdown occurs and there is no risk of damage to the optical fiber cable. Also, the upper fixing bracket 15 and the lower fixing bracket 23
By filling the cable with a waterproof compound, rainwater or the like adhering to the cable is prevented from penetrating the surface of the optical fiber cable A within the optical fiber cable terminal 1.

As shown in FIG. 2, the optical fiber cable terminal 1 is installed at the terminal end of an optical fiber cable that is wrapped around or attached to an energized conductor such as an overhead power transmission line or distribution line, and into which the above-ground part of the optical fiber cable is drawn. be done. FIG. 2 shows one embodiment of the present invention, where A is an optical fiber cable, B is a energized conductor such as a power transmission line or distribution line, and the energized conductor B around which the optical fiber cable A is wound is a substation station. At the steel structure C, it is held down by the detention insulator D and the suspension clamp E, and from the jumper part B1 between the detention clamp E and the clamp G supported by the suspension insulator F, by this clamp G and the clamp J of the suspension insulator H on the ground. Vertical bus section B2 with upper and lower parts held together
Lower it to near the ground and pull it from the clamp J to the cable head K on the ground.

Further, the optical fiber cable A wound or attached to the energized conductor B is passed through a protection tube, for example, a protection tube L containing a reinforcing wire, and is vertically connected to the jumper portion B1 of the energized conductor B. It is drawn into the optical fiber cable terminal 1 installed on the ground along with the bus section B2. M is a case for storing the extra length of the optical fiber cable, and N is a metal fitting for holding the protective tube L. L1 is the optical fiber cable insertion protection tube part attached to the jumper part B1 of the energized conductor B, L2 is the lowered part of the optical fiber cable insertion protection tube attached to the vertical bus part B2, and L3 is the part attached to the mount 27. This is the part of the optical fiber cable insertion protection tube that is led into the installed optical fiber cable terminal 1.

The above-mentioned optical fiber cable terminal 1 connects its live part, for example, the upper metal fitting part, to the vertical bus part B2 of the energized conductor B by bridging it with a bridging conductor 30 such as a steel-core aluminum stranded wire. This charging part is brought to the same potential as the energized conductor B. Reference numeral 28 indicates a connection fitting that connects one end of the bridging conductor 30 to the energized conductor B, and numeral 29 indicates a connection fitting that connects the other end of the bridging conductor 30 to the upper fitting of the optical fiber cable terminal 1. A protective tube L3 into which the optical fiber cable A is inserted is attached to the bridging conductor 30, which has the same potential as the energized conductor B, and is fixed with a gripping fixture N.

The bridging conductor 30 provided as described above prevents damage to the contaminated surface of the non-metallic optical fiber cable A due to high voltage. If this bridging conductor were not present, there would be a considerable potential difference between the energized conductor B, which is at high voltage, and the optical fiber cable terminal 1, which is on the ground side. If the surface is not completely clean and is contaminated, there is a risk that a high voltage will be applied to the contaminated surface and cause damage. By drawing the metallic optical fiber cable A along with it into the terminal 1, high voltage is no longer applied to the contaminated surface of the non-metallic optical fiber cable A. Further, the non-metallic optical fiber cable portion pulled down along the vertical bus section B2 of the energized conductor B is also safe because it is not exposed to a high potential difference.

As described above, the optical fiber cable A attached to the bridging conductor 30 is drawn into the terminal 1 from the upper end of the optical fiber cable terminal 1, passed through the sleeve 2, and drawn downward to be connected to a transmission device or the like. P is a connection box that stores the extra length of the optical fiber cable.

As described above, the optical fiber cable A that is drawn into the sleeve 2 of the optical fiber cable terminal 1 and pulled out downward has its upper lead-in port and lower draw-out port connected to the upper fixing fitting 15 and the waterproof compound. 16
, and the airtight and waterproof seal between the lower fixing fitting 23 and the waterproof compound 24, preventing water from penetrating the surface of the optical fiber cable inside the terminal 1. In addition, even if the temperature changes, the upper surface of the insulating mixture 25 in the sleeve 2 remains in the reservoir 5.
Since there are no gaps within the sleeve 2, no damage to the optical fiber cable will occur due to localized electric field concentration.

In the embodiment shown in FIG. 3, the end of the bridging conductor connected to the optical fiber cable terminal 1 is
Instead of connecting the bridging conductor 30 to the lower part of the vertical bus part B2 like the bridging conductor 30 shown in FIG. This is an example, and the same reference numerals as in FIG. 2 indicate the same parts. In the embodiment of FIG. 3, the energized conductor B, which is held down by the detention clamp E of the detention insulator D in the detention structure C, connects the down conductor B3 to the cable head K on the ground. In addition, a bridging conductor 31 is used to connect the energizing conductor B and the connection fitting 29 of the live part on the upper part of the optical fiber cable terminal, and the non-metallic optical fiber cable A wrapped or attached to the energizing conductor is stored in the excess length. From case M to protection tube L4
The optical fiber cable is pulled down along with the bridging conductor 31 and drawn into the optical fiber cable terminal 1. In this embodiment as well, the live part of the optical fiber cable terminal 1 is brought to the same potential as the energized conductor B by the bridging conductor 31, and the non-metallic optical fiber cable in the protection tube L4 attached to this bridging conductor 31 is Even if the surface is contaminated, a high potential difference is not applied to the portion along the bridging conductor 31. The optical fiber cable A drawn into the optical fiber cable terminal 1 is guided downward through the extra length storage type junction box P and introduced into a transmission device or the like.

The embodiment shown in FIG. 4 is an embodiment in which the end of the bridging conductor connected to the optical fiber cable terminal 1 is connected to the jumper section of the energized conductor in the tension steel structure, and is the same as that in FIG. Codes indicate the same parts. In FIG. 4, B1 and B1 are the jumper parts of the energized conductor B held in place by the tension clamps E and E of the tension insulators D and D, respectively, on both sides of the tension steel structure C, and L5 and L6 are the jumper parts on both sides. Part B1 is the optical fiber cable insertion protection tube part attached to B1. The non-metallic optical fiber cable A wrapped around or attached to the energizing conductor B passes through the protection tubes L5 and L6, passes through the extra length storage case M, and is pulled down and inserted into the protection tube portions L7 and L8 and installed on the ground. The optical fiber cable is drawn into the optical fiber cable terminal 1. In this embodiment, the jumper part of the energized conductor B and the live part of the upper metal fitting of the optical fiber cable terminal 1 are connected by a bridging conductor 32, and the live part of the optical fiber cable terminal 1 is connected to the live part of the upper metal fitting of the optical fiber cable terminal 1. By making the electrical potential the same, attaching the protective tubes L7 and L8 through which the optical fiber cable has been inserted to the bridging conductor 32 and pulling it down to the optical fiber cable terminal 1, the bridge can be bridged even if the surface of the non-metallic optical fiber cable is contaminated. A high potential difference should not be applied to the part along the shorting conductor 32. Optical fiber cable A passed through the optical fiber cable terminal 1 and pulled out downward
is pulled out downward from the extra length storage type junction box P and connected to a transmission device, etc.

As described above, the bridging conductor 30 of each embodiment,
31 and 32 are for making the live part of the optical fiber cable terminal the same potential as the energized conductor, and the bridging conductor, the means for connecting the energized conductor and the live part, etc. may be changed as appropriate in addition to the above embodiments. The structure of the reservoir 5 provided in the optical fiber cable terminal can also be changed as appropriate. In addition, as mentioned above, the protection tubes L3, L4, and L7 are connected to the bridging conductor.
, L8, and instead of inserting the optical fiber cable into this protection tube and drawing it into the optical fiber cable terminal 1, it is also possible to wrap the protection tube or the optical fiber cable around the bridging conductor and draw it into the optical fiber cable terminal 1. .

[0024]

Effects of the Invention As described above, the present invention provides a bridging conductor between the live part of the optical fiber cable terminal and the energized conductor, and wraps or attaches the lead-in part of the non-metallic optical fiber cable to the bridging conductor. Therefore, even if the surface of the non-metallic optical fiber cable is contaminated, there is no risk of damage as high voltage is not applied.In addition, a reservoir is provided at the upper end of the cannula, and the upper surface of the insulating mixture filled in the cannula is Therefore, even if the insulating mixture expands and contracts due to temperature changes, there will be no voids on the top surface of the insulating mixture in the sleeve, and local electric field concentration will not occur, preventing damage to the optical fiber cable. There is no such thing.

[Brief explanation of drawings]

[Fig. 1] Cross-sectional view of one embodiment of the optical fiber cable terminal of the present invention

[Fig. 2] Drawing state diagram of one embodiment of the optical fiber cable terminal device of the present invention

[Fig. 3] Optical fiber cable drawing state diagram of another embodiment of the present invention

[Fig. 4] Optical fiber cable drawing state diagram of still another embodiment of the present invention

[Figure 5] Diagram showing a conventional example of an optical fiber cable being pulled in

[Explanation of symbols]

1; Optical fiber cable terminal 2; cannula 5; Reservoir 25, 25′; Insulating mixture 30, 31, 32; Bridging conductor A: Optical fiber cable B; Charge conductor

Claims (2)

[Claims] [Claim 1] A bridging conductor is provided between a live part of an optical fiber cable terminal on the ground side of an optical fiber cable that is wrapped around or attached to a energized conductor such as an overhead power transmission line or a distribution line and the energized conductor. An optical fiber cable terminal device comprising: a non-metallic optical fiber cable wrapped around or attached to the bridging conductor and led into an optical fiber cable terminal. 2. A reservoir is provided at the upper end of the cannula of the optical fiber cable terminal and communicates with the cannula, and the insulating mixture is filled into the cannula so that its upper surface exceeds the upper end of the cannula and enters the reservoir. The optical fiber cable terminal device according to claim 1, characterized in that: