Specifies requirements for fuses incorporating enclosed fuse-links, with breaking capacities not less than 6 kA, intended for the protection of a.c. power-frequency circuits of nominal voltages not exceeding 1000 volt or d.c. circuits of nominal voltages not exceeding 1500 V. It should also be applied to fuse-links for inclusion in fuse-switch combinations. Includes definitions, conditions for operation in service, characteristics, markings, standard conditions for construction and tests. It is structured to be closely aligned with IEC 269-1.