FI86349C - Wiring design for an electrical distribution connection - Google Patents

Description

1 86349

The present invention relates to a line structure for an electricity distribution connection, which line structure is primarily intended to be installed in the ground.

Conventional ground-mounted conduit structures are cables that are installed on a sand base suitable for a cable trench and covered with separate rollers of 10 protective trowels and sand before the cable trench is finally covered. Such a method of laying cables on the ground requires a relatively large amount of earthmoving and gutter installation work, which always has to be done again in connection with cable operations, such as repairs or replacement work. This means quite often repeated tearing of streets, roads and pavements. In addition, underground cables installed in this way are relatively susceptible to damage caused by excavators, as the cables are hardly able to slide in the axial direction due to traction, resulting in

It is an object of the present invention to provide a conductor structure primarily intended for installation in the ground, which solves a number of problems and disadvantages associated with conventional underground cable installations.

This object is achieved by a conductor structure 30 according to the invention, characterized in that it comprises a pipe made of strong, weather- and frost-resistant plastic and at least one conductor fitted inside it, which is exposed or comprises only a sheath acting as sufficient electrical insulation. In this conductor structure, the conductors can be either discrete or twisted or twisted. Most importantly, however, the strong, weather- and frost-resistant plastic pipe surrounding the conductor can be used both as a mechanical protection for the conductors and as an electrical protection structure, as a result of which the insulation of the conductors can be significantly simpler than at present. Primarily, only a single-layer cover with sufficient electrical stress resistance is required, and protective gutters are generally not required.

When using the conductor structure according to the invention, the power transmission capacity of the connection 10 can be easily increased either by changing the conductor drawn into the pipe to a larger one or by adding conductors to the pipe. In the case of an electricity distribution network, the line structure can also be used as a structure to facilitate the automation of the network, since control cables related to the remote operation of the network can be laid on it from the beginning or possibly later.

In contrast to normal underground cable installations, in the cable structure according to the invention, backup connections can be provided at low cost by drawing one additional conductor to the pipe when making 20 electricity distribution connections, which is switched on, for example, if one phase of the three-phase distribution connection is damaged. Providing such a backup connection is very advantageous compared to the current only possible use of an additional kaa-25 game. It is also possible to install only plastic pipes on the ground, for example in connection with street construction work, to which the wires are laid only when necessary. This avoids premature investment in conductors.

A further advantage of the conductor structure according to the invention is that, due to the simple removability of the conductors and their simple insulating structure, they can either be reused for new installations or the metal contained therein can be easily recovered.

. Another significant advantage of the conductor structure according to the invention is that there is little need to dig up the once-installed conductor structure when increasing the power transmission capacity of the connection, either by replacing the conductors or by pulling new conductors into the pipe.

Since the pipe of the conductor structure according to the invention is preferably uniform over the entire length of the connection and is thus fed, for example, from a coil, the installation of the conductor structure according to the invention is suitable for plowing, so that the installation is simple and efficient.

The conductor structure according to the invention is also not susceptible to excavator damage, because the conductors are located inside a strong plastic pipe, which in itself protects the conductors from mechanical damage, and on the other hand lower risk of rupture. In addition, the damage to the conductor can be repaired relatively easily, for example by removing the damaged point from the pipe and replacing the new conductor. This avoids making cable splices for at least short connections. On the other hand, when the conductors themselves need repair, it is most often solved with one repair extension 25 instead of the usual two, based precisely on the extra length of conductors in the pipe.

The structure of the conductor structure according to the invention will now be described in more detail with reference to the accompanying drawing, Fig. 1 shows a cross-section of one embodiment of the conductor structure according to the invention, Fig. 2 shows a cross-section of another embodiment of the conductor structure dosage form.

Figure 1 shows a cross-section of a pipe structure according to the invention comprising a pipe 1 made of strong, weather- and frost-resistant plastic, which can thus be, for example, HDPE plastic. Inside the embodiment of Fig. 1, four insulated conductors 2 are arranged inside this pipe, the single-layer insulation of which is also made of strong weather- and frost-resistant plastic, for example HDPE or PEX plastic. In addition, in the embodiment of Fig. 1, another uninsulated conductor 3 is arranged inside the pipe 1. The conductors 2 and 3 may have been placed in the pipe either at the factory during or after the manufacture of the pipes 1 or may have been laid in the pipe only after it has been installed in the ground.

Figure 2 shows another exemplary embodiment of a conductor structure 15 according to the invention, in which a conductor connection formed of twisted or twisted conductors 4 is arranged in the pipe 1. These conductors 4 correspond in structure to the conductors 2 of the embodiment of Figure 1.

Fig. 3 shows a third exemplary embodiment of a conductor structure according to the invention, in which an insulated conductor 2, an uninsulated conductor 3 and a cable 5 are arranged in the pipe 1. This embodiment of Fig. 3 is an example that the conductor structure according to the invention can. 25, although the placement of such cables as part of the conductor structure according to the invention does not make much economic sense and the placement of such a conventional cable inside the pipe 1 belonging to the conductor structure according to the invention does not form an object of the present invention.

When manufacturing the conductor structure according to the invention, the conductors can, as already mentioned above, be placed in the pipe either at the factory or only in connection with installation. Thus, the conductors can be placed in the pipe already during the manufacture of the pipe .35 or they can be laid in the pipe already at the factory or 5 86349 also during installation. The conductors can also be drawn into the pipe by "blowing", which means using compressed air to provide traction on the conductors. The tight and pressure-resistant structure of the pipe 1 offers the possibility of such an installation method. Another option is to place a traction cord in the tube during its manufacture to facilitate subsequent traction of the conductors. The conductors can also be placed in the pipe by making a longitudinally split incision in the pipe 1, from which the conductors 10 can be inserted into the pipe and then gluing the incision in the pipe 1. Such an incision can be made either already at the factory or why not at the time of landing. As alternatives for slitting the pipe, it would still be conceivable for the pipe to be formed from a plate-15 or a chute or from two chutes to be glued together, in which case the desired conductors would be fitted inside them before closing. However, using all of the above installation methods, the end result is, for example, a conductor structure of the type shown in Figures 1-3 with a strong and uniform plastic tube surrounding the conductors. This plastic pipe is most preferably made continuously in its longitudinal direction, so that there are as few extensions as possible in the installed conduit structure.

The conductor structure according to the invention has been described above on the basis of only some exemplary embodiments and it will be understood that some changes may be made thereto, in particular with regard to the type and number of conductors, without departing from the scope of the appended claims. Thus, one of the conductors 30 may be a telecommunication or light line for the transmission of information, which also preferably lacks at least the outermost protective layer.

Claims (4)

6 86349 A cable structure for an electricity distribution connection, which cable structure is intended primarily for installation on the ground 5, characterized in that it comprises a pipe (1) made of strong, weather- and frost-resistant plastic and at least one conductor (2, 3) arranged therein, exposed or comprises only a cover which acts as adequate electrical insulation. Conductor structure according to Claim 1, characterized in that the conductors (2, 3) are separate. Conductor structure according to Claim 1, characterized in that the conductors (4) are twisted and / or twisted. Conductor structure according to one of the preceding claims, characterized in that the pipe (1) is uniform over the entire length of the connection. 7 86349