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According to the different flame-retardant materials of cables, flame-retardant cables are divided into halogen-containing flame-retardant cables and halogen-free low-smoke flame-retardant cables.
The halogen-containing flame-retardant cable's insulation layer, jacket, outer sheath, and auxiliary materials (bags and fillings) are all or partially made of halogen-containing polyethylene (PVC) flame-retardant materials, and therefore have good flame-retardant properties.
The halogen-free, low-smoke flame-retardant cable has all or part of the insulating layer, sheath, outer sheath, and auxiliary materials (bags and fillers) made of Halogen-free, cross-linked polyethylene (XLPE) flame retardant material. Better flame-retardant properties, and no halogen acid gas is emitted when the cable is burned, the cable emits less smoke, and the amount of smoke is also close to the recognized "low smoke" level.
Fire-resistant cable: It means that the sample is burned in the flame under the specified test conditions, and it can still maintain the normal operation performance within a certain period of time. Its fundamental characteristic is that the cable can still maintain the normal operation of the line for a period of time under the burning conditions. In layman's terms, in the event of a fire, the cable will not burn at once and the circuit will be safer. Therefore, the main difference between the fire-resistant cable and the flame-retardant cable is that the fire-resistant cable can maintain the normal power supply for a period of time when the fire occurs, and the flame-retardant cable does not have this characteristic. The cable is mainly used in emergency power supply to users of fire-fighting equipment, fire alarm equipment, ventilation and smoke exhaust equipment, guided lights, emergency power outlets, emergency elevators and other power supply circuits. Ordinary fire-resistant cables are classified into Class A and Class B: Class B cables can withstand fire for at least 90 minutes in a flame at 750°C to 800°C and at a rated voltage and the cable is not broken (ie, the 3A fuse is not blown). On the basis of improving the manufacturing process of the refractory layer and increasing the refractory layer, a Class A fire-retardant cable was also developed. It can withstand the fire for at least 90 minutes in the flame at 950°C to 1000°C and at rated voltage and the cable is not broken down ( That is, the 3A fuse is not blown). Class A fire-resistant cables have better fire resistance than Class B.
When selecting the cable, the correct optional cable for the place of use should be distinguished.
Flame-retardant cable: refers to the test specimen under the conditions of the test, the flame is burned, after the removal of the test source of fire, the flame spread only within a limited range, the residual flame or residual light within a limited time can extinguish the cable. Its fundamental characteristic is that in the event of a fire, it may be burned out and cannot be operated, but it can prevent the spread of fire. In layman's terms, if the cable is misfiring, it can limit the burning within a certain range, and it will not create sprawl, keep other equipment, and avoid causing greater losses.