BS 2950 is a British standard that relates to non-rewirable cartridge fuse-links for use in conjunction with telecommunication or light electrical equipment where the prospective fault current of the circuit will not exceed ten times the rated current of the fuse-link. Fuse links of two grades, A and B, which blows at two or three times their rated currents respectively, are specified for rated currents of 250 ma and below.
BS 2950 does not specify surge resisting characteristics, but for the guidance of those who wish to make tests of these characteristics, information on a suitable test is given in Appendix A.
BS 2950 on cartridge fuse-links for telecommunication and light electrical apparatus is useful for:
A cartridge fuse is a fast-acting safety device that protects cables, power lines, and equipment in electrical systems against overloads and short circuits. A cartridge fuse's primary purpose is to safeguard systems and human life.
The primary object of BS 2950 is to specify cartridge fuse-links that experience has shown to be adequate for this class of service, without adding to their cost by requiring expensive proving tests. Moreover, since the cost of producing fuse-links giving a close degree of protection increases with the smaller currents, and critical protection is not always required within this range, two classes of fuse-link, Grades A and B, are specified, for rated currents of 250 ma and below, which will blow at two or three times their rated currents respectively.
BS 2950 provides its users with specifications for end caps, preferred rated currents and voltages, blowing current, breaking capacity, and marking. Using BS 2950 guidelines enhances surge protection, safety, quality assurance, and durability for longer service life.