Flame-retardant cable refers to the cable in which the sample burns under the specified test conditions, and after the test fire source is removed, the flame spreads only in a limited range, and the residual flame or combustion can extinguish itself in a limited time. The most fundamental feature is that once a fire breaks out, it may be burned out and unable to run, but it can prevent the fire from spreading.
Generally speaking, in the case of wire fire, the combustion can be limited to a local range without spreading, and other equipment can be saved to avoid causing greater losses.
Extended data:
IEC flame retardant rating:
In order to evaluate the flame retardant performance of cables, IEC has formulated three standards: IEC60332- 1, IEC60332-2 and IEC60332-3 respectively. C60332-1and IEC60332-2are used to evaluate the flame resistance of inclined and vertical laying of single cable (corresponding to GB12666.3and GB12666.4standards in China).
Yi C60332-3 (domestic counterparts GB 12666.5-90, GB 12666.5 has been replaced by GB/T 18380.3-200 1) is used to evaluate the flame retardancy of bundled cables when they burn vertically. In contrast, bundled cables need to meet the requirements of flame retardancy when burning vertically.
The difference between flame-retardant cable and fire-resistant cable;
Ordinary people can easily confuse the concepts of flame retardant cable and flame retardant cable. Although flame-retardant cables have many advantages that are more suitable for chemical enterprises, such as low halogen and low smoke, generally speaking, flame-retardant cables can replace flame-retardant cables, but flame-retardant cables cannot replace flame-retardant cables. Their differences mainly lie in:
1 principle
The principle of fire-resistant cable is different from that of flame-retardant cable. The flame retardant principle of halogen-containing cables depends on the flame retardant effect of halogen, and the flame retardant principle of halogen-free cables depends on the precipitation of water to reduce the temperature to extinguish the fire. The fire-resistant cable relies on the fire-resistant and heat-resistant characteristics of mica material in the fire-resistant layer to ensure that the cable can work normally in case of fire.
2 the difference between structure and material
The structure and materials of fire-resistant cables are also different from those of flame-retardant cables.
The basic structure of flame retardant cable is:
(1) The insulating layer is made of flame retardant material.
(2) the sheath and the outer sheath are made of flame retardant materials;
(3) The package and filler are made of flame retardant materials.
In a fire-resistant cable, a 1 fire-resistant layer is usually added between the conductor and the insulation layer, so it is theoretically possible to add a fire-resistant layer to the structure of the fire-resistant cable, thus forming a fire-resistant and fire-resistant cable, but it is not necessary in practice.
Because the fire-resistant layer of fire-resistant cable is usually directly wound on the conductor with multi-layer mica tape, it can withstand long-term combustion, and even if the polymer at the flame is burned, it can ensure the normal operation of the line.
References:
Baidu encyclopedia-flame retardant cable