Power cable

Power cable – is a product of designed to conduct electrical energy from the site of its generation to different drain objects (industrial establishments, objects of municipal and transport purposes, etc).

The main constuents of the electric power cable are its core, the core insulation and coating. Some cables may contain armor, bedding and screen, depending on its purpose. The marking of power cables points out elements and materials of its production.

The marking can be interpreted using the following method: the first letter designates the metal constituent of the wiring, the second letter stands for the type of insulation. The third letter designates the type of coating, and the last letter indicates presence or absence of armor. For example, cable marking АВВГ means that it has got Aluminium core (A), PVC insulation (B), coating (B), doesn't contain armor (Г). Power cable marking ВВГ contains the same elements except core, which is made from copper. It stands to mention that power cable ВВГ is most popular. It may be used for indoor laying, in rooms, as well as for outdoor installation.

Besides ВВГ power cables, the following power cables which are often used ВВГнГ (fire-resistant), ВВГнГ Is (fire-resistant with low fume emission), ВВБбШв (cable with armor). All the mentioned power cables are made from PVC insulation.

In recent times the power cable has become one of the most utilized cables by manufacturers and households as it provides a stable power source to household devices. A power cable can contain up to 4 conducting wires, and the wires themselves may be encased in a metallic or non-metallic shell, hidden under a protective cover.

What the choice of shell or casing can be made depending on where the location where the cable is installed, as well as its future operating conditions.

The main elements of all types of power cable are: conductors, screens, insulation, shell and integument. Depending on the purpose and conditions of the cable, the integument and the screen may be excluded.

The main types of power cable are: power cable with plastic insulation (AVVG, AVBbShv, VVG, NYM), power cable with rubber insulation and sheath (CG) and power cable with oiled paper insulation (AAB, ASB, AAShv, BPI). The power and operation characteristics of the power cable are - rated supply voltage, section and the number of cores, acceptable climatic conditions for operation and application area.

 Selecting a power cable

At first, the conductor material must be taken into account. There are 2 metals used for the construction of the cable wiring: copper and aluminum. Copper conductors have all the parameters and characteristics of aluminum are now considered superior, however, there is a large price difference between copper and aluminum counterparts. Special attention should be paid to the cross-section of the power cable. Depending on the alleged loads that will test the cable network; selecting the cross section can be permissible under the terms of heating and on the economic current density. The Choice of insulation to the power cable depends entirely on the conditions of installation. Cables insulated with BPI and the metal shell withstand moisture and mechanical damage, however it is not recommended to lay this type of cable on ground with a strong slant or verticality, as there is a possibility of "run-off" oil colophonium impregnating the insulating layer, which can cause premature aging of the insulation. Such deficiencies are absolutely absent in cables with plastic insulation (eg AVVG and VVG). However, the insulation on the PVC based of has a dielectric parameters worse than other types of insulation. The most optimal in all regards is a cable insulation of cross-linked polyethylene. But it also has drawbacks: due to lack of a protective coating. Cabling with an air of isolation is allowed only in special boxes and ducts.