Cable installation: ways of laying, description of technology and recommendations of specialists

Power supply plays an important role in human life. It is delivered to each house or facility using power cables. And then the internal wiring provides electricity to individual rooms. Cable laying and installation are carried out by different methods. Each method has special requirements. For example, the installation temperature of the cable in the room should be from -20 ° C to + 40 ° C.

Basic information about wire installation

The main point in the implementation of electrical installation activities and not only is the availability of project documentation, compiled by government agencies. The installation of the cable must take place in accordance with certain requirements, which depend on the location and conditions of the installation.

For example, a special type of cable is used for the outside and underground. The engineer-designer is engaged in the design and search for the place of installation of electrical networks. At the same time, he must take into account not only safe options for laying, but also personal preferences of the customer. Let's consider ways of laying cables in detail.

Outdoor

Experts say that this is the cheapest and fastest way. If the wire gets damaged, then its repair does not require much effort. The cable is mounted on the walls with the help of special brackets. This method is not very popular, so it can rarely be found.

Concealed wire routing

Before you perform the installation of the cable, it is necessary to perform wall shutting.

This process consists in making a hole in the wall, the width of which depends on the type of cord being laid. This method gives the room not only a neat appearance, but it is also quite safe. It has its positive and negative sides. The advantages include:

• Absence of wires on the walls;
• Inaccessibility for children and animals;
• Protection of the wire against moisture and mechanical damage.

The installers note only one drawback of this method. This is a great chance to stumble on the cable while drilling. To avoid this, it is necessary to have a power supply project. Damage to the wire makes it difficult to repair it.

Gasket in the box

Installation of wires and cables in this way can be found in office buildings, country houses, shops and enterprises.
Boxes are of two types: with a lid opening and sealed. To give a more pleasant appearance, in addition acquire corners and tees. This method does not take much time and effort. The size of the box depends on the number of wires to be laid. If necessary, you can easily get to the cables and perform repairs.

Underground gasket

The installation of a power cable in this way requires considerable funds for earthworks. The cable can be routed through a special tunnel or simply buried. At the same time, the degree of its protection depends on the electricity supply project.

Also consider the operating conditions of the cable. Earthworks are performed manually or with the help of technology (depending on how deep the trench is needed).

Air-laying

The installation of electrical cables is carried out through the air from the post to the post in two ways:

• On porcelain insulators - the connection from the post to the house takes place with the help of a porcelain insulator;
• With the help of a stretcher - the laying and installation of the wire takes place with the help of a lanyard, a cable, a coupler and clamps. The first device serves to attach the cable and adjust the degree of tension. Its size and thickness depend on the weight and length of the cable. To deliver it to the top of the column, use the belt and claws.

Gasket temperature

Any cables are laid only at a positive temperature, regardless of the type of insulation and voltage. If there is a need to install at a negative temperature, then the ground should be warmed for a start. Why do they do this?

Paper insulation impregnated with a special oil, which under the influence of negative temperatures loses its viscosity and lubricity. If it does not warm up, cracks may appear at the cable bends. In addition, the cable structure will not lubricate the paper, but glue, which will lead to its rupture. In any case, negative temperatures will affect the destruction of the material, and, consequently, lead to a decrease in electrical strength.

Indoors it is allowed to lay cables without heating. And the temperature range is from minus twenty to zero degrees Celsius.

Mounting the cable clutch

Consider the most popular types of these elements and their purpose.

Cable coupling. It is designed to connect the ends of the wire and their supply to power lines (usually air) and to high-power electrical appliances.

Cable end clutch. Serves for supplying cables to electrical appliances that can be located both indoors and outside.

Connecting cable part. Used to fasten two cables together.

Experts recommend that before using the coupler remove the pieces of factory insulation located on the end of the cable. This procedure is carried out in the following order: removal of jute coating, paper or fibrous base of all insulation, as well as of individual strands. This removal is called stepwise. The dimensions of the cutting are given in the reference literature and depend on the brand and the thickness of the cores.

Before connecting cables with paper insulation, the moisture content should be checked.

To do this, cut off a piece of paper from the end of the insulation and lower it into a container with preheated paraffin (temperature 140-150 ° C). If there is moisture on the paper insulation, a small amount of foam will appear.

Epoxy and lead types of couplings are used to connect cables with voltages up to 10 kW. The main advantage of the former is resistance to aggressive substances. Their properties are similar to locking clutches. Therefore, they are also used to connect cables with paper insulation. They are made by mixing epoxy components with a special thickener. The last element is added to the epoxy mix just before the coupling is made. This is necessary in order for the curing process to pass faster.

When using epoxy couplings when laying in tunnels or canals, it is necessary to provide them with reliable protection. Typically, it is a steel pipe with a diameter of at least 150 millimeters and a length of 1250 millimeters. Two layers of asbestos are laid on its interior. The edges of the pipes are closed with lids made of asbestos cement.

Lead-free couplings are used for cables with voltages up to 10 kW. They are used together with shells, which are lead pipes of different diameters and lengths. These figures depend on the thickness and voltage of the wire.

The ends are cleaned in the same sequence as for the epoxy couplings. Then a lead sleeve is put on, and the veins are twisted or connected by soldering. After the installation is complete, the factory insulation is restored using paper soaked in oil. To restore the insulation near the location of the cores use the same cable paper.

The lead couplings are located only inside the building, enclosing them in special steel protective casings. In case of laying by underground method, leaky casings or pipes made of fiberglass are used.

They will protect the coupling from mechanical damage. Another type is the strap-and-socket couplings. They serve to limit the differences in the levels of power cables having impregnated paper insulation.

Conclusion

In order to provide a building or structure with electricity, it is necessary to properly install the power cables. To do this, there are many methods, for example, underground and air. There are also ways to install indoors. Installation of cables takes place after the preparation of project documentation. This procedure is performed by design engineers. The whole process is controlled by state authorities in the field of electricity supply. As the connecting elements serve different types of couplings. They can connect both cables with each other, and be attached to various electrical appliances of large and low power.

So, we found out how to install electrical cables and wires.