Determines the service conditions, design and construction, type approval and routine tests of l.v. single-phase fuses for pole-mounting either as a single-phase or one phase of a three-phase a.c. system, at a nominal 240 V between phases and neutral at a frequency of 50/60 Hz, the neutral being effectively earthed. Restricted to a fuse which is rated at a continuous current of 315 A with a 400 A overload capacity, and which accommodates wedge-type cartridge fuse-links of 82 mm terminal centre spacing in accordance with ESI 12-8. Fuses which accommodate end-cap fuse-links for use up to 200 A are excluded. It is recognized that current designs of such equipment do exist and it is not intended that the issue of this Standard should necessarily preclude their continuing use.