Service conditions of fire resistant cables
Fire resistant cables are widely used in high-rise buildings, underground railways, underground streets, large power stations and important industrial and mining enterprises, such as power supply lines and control lines of emergency facilities such as fire-fighting equipment and emergency guide lights.
1. Service conditions
AC rated voltage: U/ U (V) series: 600 / 1000V, K Series: 450 / 750V, B series: 450 / 750V
2. Maximum long-term operating temperature of cable
(1) Insulation and sheath of olefin resistant polyfluoroethylene: 70 ℃ and 105 ℃; XLPE insulation: 90 ℃;
(2) Fluoroplastic insulation and sheath: 220 ℃ and 260 ℃; Fluoroplastic insulation and 105 ℃ flame retardant polyvinyl fluoride sheath: 90 ℃ and 125 ℃.
(3) , low halogen and low smoke flame retardant PVC insulation and sheath: 70 ℃; Halogen free low smoke flame retardant polyolefin insulation and sheath: 90 ℃ and 125 ℃. Thermometer silicone rubber cable fire resistant cable
3. Minimum ambient temperature:
(1) . flame retardant PVC insulation and sheath: fixed laying - 40 ℃; Non fixed laying - 15 ℃;
(2) Fluoroplastic insulation and sheath: fixed laying - 60 ℃; Non fixed laying - 20 ℃;
4. The safe laying temperature of cables shall not be lower than 0 ℃.
5. Fire resistance characteristics:
Comply with iec331 and gb12666 6 Provisions
Flame temperature 750 ℃, flame temperature 950 ℃ - 1000 ℃
Flame temperature 750 ℃ - 800 ℃
Combustion time 3H combustion time 90min combustion time 90min
Cooling time 21h additional voltage rated voltage additional voltage rated voltage
Additional voltage rated voltage additional current 3A additional current 3A
Additional current 3A class a class B
6. Recommended allowable bending radius for laying: non armored and braided shielded cables shall not be less than 6 times of the outer diameter of the cable;
Steel tape armored cable shall not be less than 12 times of the outer diameter of the cable; Thermometer silicone rubber cable fire resistant cable
Fluoroplastic insulated and sheathed cables shall not be less than 8 times the outer diameter of the cable.

