laying wiring procedure in the ripple it is often accompanied by a lot of mistakes. The most common of these are associated with the features of the material used to produce corrugated hoses.
It is believed that the use of corrugations makes it possible:
- protect the wires from the propagation of combustion;
- protect them from external mechanical influences and damage.
All who hold this view, refer to the supposedly available in the SAE recommendations, but they do the wrong conclusions.
Typical errors of fire properties of the material
It is widely believed that the corrugated hose are able to provide fire protection. At the same time, some experts agree with this and use the corrugation (pictured below) when installing wiring in a home or apartment.
Professional it is clear that they do it by refusing to use expensive metal tubes (trays).
Important!According to the manufacturer (see the technical characteristics of the material on their websites) corrugated pipe allows only a "not support combustion."
All variants of its use are given in Table 2.1.3 SAEConcerning the rules for selecting entries of types and methods of safe wiring. Particularly important in this Annex the following lines: "The protected elements wiring sheathed in fireproof plastics". That is, it is assumed that the corrugated hose and without modern copper wires in the shell (VVGngLS, in particular) are already protected in the fire relation.
Attention also should be paid to the use of the corrugations as a kind of laying of non-combustible materials used in the installation of wires on wooden bases. But as a non-flammable it is not - then applies obviously for other reasons (not safety-related).
Mechanical protection and the possibility of replacing
It is conceivable that the application of the corrugated pipe is specified in connection with the possibility of mechanical protection against rodents and, in particular. But even here, a discrepancy is detected, since neither that nor the other case it does not save and easily destroyed. Its easy to crack household pests, and by the fall of a heavy metal object is damaged and he flute and shell protective wiring.
A common mistake is the reference to the fact that, if necessary wires laid in the corrugations can be easily replaced with new, undamaged wires. This statement is only partially true, because only applies to straight sections laying tracks. In the presence of replacement lived ripple turning into real torture (pictured below) in the angular wiring turns (a right angle or less).
Simply completely dismantle the system and in the open air again prodernut harness with wiring in the corrugated hose.
It turns out that the only justifiable purpose of this type of protection - the possibility of an orderly and secretive laying wire veins included in the wiring.
In support of the fallacy of common opinions about the ripple can draw the following conclusions:
- Corrugated pipe for the most part provide a hidden electrical wiring, that is simply used to organize the assembly of wire strands.
- They are not able to protect them from accidental ignition and can not be used as a liner under the combustible base.
- If necessary, perform internal wiring of flammable materials require steel pipes (pictured below).
Additional Information: In extreme cases, organizational techniques can be used for protection. Recent reduced to the enclosure of the cable layer of non-combustible material (of plasterboard sheets GCR, for example).