The desire to save money when connecting various household appliances or laying electrical wiring often leads to very sad consequences. The question arises: how to ensure the normal and safe functioning of the system, but at the same time avoid unnecessary expenses? The VVGng LS cable is one of the best options for home use and is very popular with electricians. Why?
Deciphering the marking
Before giving a description of the properties of this conductor or its technical characteristics, you should understand: what this abbreviation actually means and the numbers that follow it. Otherwise, it is not clear what qualities, for example, a VVGng LS 5x16 cable has, and how does it differ from a VVGng LS 5x2.5 cable?
With letters, everything is quite simple:
- The absence of the letter "A" at the beginning indicates that the cable is copper.
- Two letters "B" indicate that both shells, outer and inner, are made of polyvinyl chloride.
- The symbol "G" denotes a bare wire. It should not be used when laying underground or where there is a possibility of physical damage without additional protection.
- "Ng" - the property does not support combustion, the addition "LS" indicates that when ignited, smoke emission will be minimal. The abbreviation "LS" ("LS") means "low smoke", that is, "little smoke".
There may be more symbols, for example, VVGng cable and frLS 3x1.5. The decryption in this case will be as follows:
- The symbol "a" indicates that the wire can be used in group laying.
- The abbreviation "fr" - the presence of additional protection against fire due to mica materials.
- There may be an additional letter "p". A feature of such a wire is the flat arrangement of the cores in the wire.
The numbers after the letter code indicate the number of conductive wires and their cross section.
For example, the VVGNG LS 4x25 cable has 4 cores, each with a cross section of 25 mm2, and the VVG Png a LS 3x1.5 cable has 3 of 1.5 mm2, the VVGng LS 5x16 cable has 5 cores with a cross section of 16 mm2.
Wire construction
VVG wireng can contain up to 5 conductive wires. Depending on the characteristics, they can be assigned the first or second class in accordance with GOST 22483.
- In their form, the veins are sector or round.
- Each core is individually insulated with PVC. Its thickness should be at least 0.3 mm. The insulation must fill all the gaps between the cores, leaving no voids.
- The cores can be made in the form of a single wire or twisted from several. In the latter case (this is more typical for sectoral wires), manufacturers can abandon individual PVC insulation by covering the overlap with a layer of thermally bonded fabric or polyethylene terephthalate film.
- As a rule, current-carrying conductors are marked in different colors for convenience during installation work.
- The cable can have ground wires and zero wires. They can differ not only in color (grounding - yellow-green, zero - blue), but also in cross-sectional area. In this case, this is also displayed in the wire marking, for example, VVGng LS 5x10 + 1x5 (N).
The size of the cross section of the cores directly depends on the expected load: the thicker the core, the more power the current can be transmitted through it. Accordingly, the weight of the wire also increases. So, a kilometer of cable (namely, in such units the weight for this product is calculated) VVGng LS 5x10 will pull 756 kg, and the same section of cable VVGng LS 5x16 will already weigh 1103 kg. More accurate data are given in special tables.
Products of this type are available for voltages of 660 V and 1000 V at a standard AC frequency of 50 Hz. The wires in this case will differ in the thickness of the insulating layers, and therefore in diameter.So, the VVGng LS 3x2.5 cable for 660 V has a nominal outer diameter of 9.3 mm, and the same cable, but rated for 1000 V - 10.2 mm.
Application
A power cable, for example, VVGng a LS 3x1.5, is intended for laying indoors, where the presence of people is implied. This is facilitated by its ability not to sustain combustion and release a minimum amount of toxic substances when heated. It can be houses, offices, shops and so on.
Laying of wires of this type is carried out at a temperature not lower than -15 ° C, otherwise additional heating will be required.
The operating temperature range of the VVGng LS cable is from -30˚С to +50˚С. The wire does not lose its properties for a long time even if it heats up to + 70˚С during operation, and starts burning only at + 400˚С.
During installation, the minimum bending radius of the conductor should not be less than 7–10 of its outer diameters.
The leading manufacturers of VVGng LS cables in Russia are domestic companies:
- Moscow CJSC "Moskabelmet";
- St. Petersburg CJSC "Sevkabel";
- Podolsk ZAO NP Podolskkabel;
- Smolensk LLC "Concord".
Subject to the operating conditions and periodic inspection of the insulation, manufacturers promise a 30-year period of normal use of the cable and give a five-year warranty from the date of wiring.
