Characteristics of the VVG power cable: types of wire, decoding and application

It is difficult to imagine a modern apartment without electrical appliances. Therefore, in the event of a failure of the electrical wiring, it becomes necessary to replace it with a new one. Due to its quality and inexpensive price, VVG power cable is more in demand than others. But the variety of cable products is sometimes difficult to buy. The seller's consultation and decoding, which is applied to the insulating layer, will help you choose a quality product.

Types and forms of VVG cable

The scope of use of any product depends on the material from which it is made, on its modification and appearance. To choose the right cable correctly, you need to know its decoding. The decoding of VVG is as follows:

1. If there is no letter A in front, this means that the conductors are not aluminum, but copper.
2. The letter B denotes the material from which the core insulation is made - PVC (polyvinyl chloride).
3. Another B gives an indication of the insulation material of the product itself - this is also polyvinyl chloride.
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4. G denotes no additional protection.

Thus, the VVG cable is a thick wire consisting of several copper conductors and PVC insulation. Each core is different in color, which helps to identify phase, ground and neutral when working with wiring. They are all twisted together and protected by a PVC sheath. The wires can be single-core (a combination of the letters "coolant" is added to the name) or stranded. Single cores are mainly used for work in private houses.

In rooms that are especially prone to fire (wooden buildings, children's and medical institutions), it is advisable to use a cable with a reduced flammability index. It is marked with a combination of small letters "ng" - VVG ng. There are several types of VVG cables, resistant to combustion, their decoding is as follows:

1. VVG ng - is. When burning, almost no smoke is emitted (is - from the English "low smoke", which means "little smoke"). Under the new rules, it is not used in institutions where the elderly and children are kept.
2. VVGng - fris. It is considered very reliable, since the conductors are protected here by tapes with elements of mica. This type is used in factories and in hazardous areas.
3. VVGng - LSLTx. Low flammability cable with non-toxic smoke, maintains working condition in case of fire. Can be used in educational institutions, boarding schools, orphanages.
4. VVGng - HF. This brand is characterized by the content in the smoke of a reduced amount of hazardous substances. HF means that the protective sheath of the conductor is made of plastic, which contains little halogens, therefore, the toxicity of the smoke is reduced.

The cable can be of any shape (see. drawing). The top layer is made of polyvinyl chloride, the gaps are filled with the same material.

Main characteristics

The quality of the cable depends not only on the type and shape, but also on the manufacturer, so before buying it is best to ask an experienced specialist for advice. In addition, the seller in the store can always present a passport for any product, which contains all the information.

The main characteristics of the VVG cable:

1. Stows at temperatures up to -15 degrees. If the temperature is lower, the wire is heated, otherwise the insulating sheath becomes hard and may break when bent.
2. Work in emergency situations is possible no more than 8 hours a day.
3. Air humidity should not be higher than 98%.
4. Fire resistance - at least 180 minutes.
5. Heating of conductors is allowed under normal operating conditions up to + 70 degrees, with overloads - up to + 90 degrees.
6. Wiring based on VVG cable can serve for 30 years.
7. The wire is stored for more than 10 years in a room equipped for this, outdoors under a canopy - 5 years, in conditions exposed to snow, wind and rain - no more than 2 years.
8. The construction length of the VVG electric wire is usually produced in 450 and 200 m. The norm is allowed to release 50 m, but provided that the amount of cable does not exceed a fifth of the entire delivery batch.

The size of the conductors of the cable section ranges from 1.5 to 240 mm. With a small cross-section, the cable is produced without filler. The veins are sectional and round. Sectional ones are usually multi-core, and round ones consist of one core. There are VVG cables with "grounding" and "neutral" conductors. In the "earthen" conductor, sometimes the cross-section is below the permissible standards, if manufacturers want to save on copper. The cross-section of the VVG wire, its decoding and its application in practice are closely interrelated.

Laying methods

There are three main ways of laying electrical wires: open, hidden, underground, and overhead.

Openthe method is carried out by structures and surfaces made of poorly flammable and non-combustible materials: gypsum, plaster, concrete. Open laying can also be carried out on suspended structures, but in no case should there be any sagging or strong cable tension here. If there is a threat of damage, it is necessary to provide protection in advance.

Additional protection is required when laying the cable on wooden surfaces. In this case, the electrical wire is laid using protection methods. On open surfaces, the cable is now almost not laid.

Method hidden wiring, which is used mainly in residential premises, is now the most common, because the wire does not go along the wall, but inside it, and nothing is visible from the outside.

For hidden installation work, there are special standards that must be strictly observed. Before laying, it is necessary to make a gutter of the walls: grooves are made in it in accordance with the size of the wire.

This work is priced slightly more expensive, but there are benefits that offset the costs:

• invisibility of the wire;
• moisture protection;
• inaccessibility to animals and children.

In this case, there can be only one minus: when drilling, you can stumble upon a cable. To prevent this from happening, before starting work, you must familiarize yourself with the electrical supply plan for the house.

Underground laying is expensive and special protection. Installation is carried out in sealed boxes along cable structures and overpasses.

Through the air, the power cable is laid from pole to pole using porcelain insulators and stretching. A belt and claws are used to deliver the wire upstairs.