Communication Field
The objective of flame-retarded test of cable under flame is to evaluate the ability of cable to suppress flame spreading under specified condition, that is, to evaluate the ability of nonmetal materials such as insulation or sheath of cable their self-extinguishment or suppression of flame spreading after they are burnt for a period of time then fire is removed. For burning in bundle its requirement is stricter than that burning in single one. Normally material of wire and cable is added with fire retardant thus wire and cable have flame retardant property when they are burning.
In burning test in bundle, Class A fire resistance is suitable for high volume of nonmetal material of cable; Class B fire resistance is suitable for medium volume of nonmetal material of cable; Class C fire resistance is suitable for low volume of nonmetal material of cable; Class D fire resistance is suitable for very low volume of nonmetal material of cable. Opel polymer is mainly used to solve problem of burning in bundle of Class C and Class D fire resistance.
