1. Skin burning method: Ironing the insulation layer with an electric iron should have no obvious dents. If there are large dents, it indicates that the material or process used for the insulation layer is defective.After a long time of burning, the insulation layer of the cable is still relatively intact. There is no smoke or irritant smell. At the same time, the diameter increases.If it is easily ignited, it can be ascertained that the insulation layer of the cable is not made of a low smoke halogen-free material (most likely polyethylene or crosslinked polyethylene).If there is a large amount of smoke, the insulating layer is made of halogenated material.
2, hot water soaking method: put the core wire or cable in 90 ℃ hot water immersion, insulation resistance will not normally fell sharply and keep above 0.1 M Ω / Km.Ω such as insulation resistance fell sharply even less than 0.009 M/Km, then without proper irradiation crosslinking process.(Polyethylene or crosslinked polyethylene insulation materials do not apply to this method of identification, can be identified using the same method).
3. Density comparison method: The density of low-smoke halogen-free material is higher than that of water, so a little insulation layer can be removed and put into water. If the material floats above the water surface, it is definitely not low-smoke halogen-free material.
Know to use low smoke zero halogen cable is good, but still on the market at present there are too many fake inferior cables, committing in the selling point of low smoke zero halogen, if don't understand distinguish true low smoke zero halogen flame retardant cable and bought substandard of defective, it will not only give us when using the use of inconvenience, as well as great potential safety hazard, so be sure to understand correctly distinguish between low smoke zero halogen cables.