Required procedures for performing design tests for high-voltage distribution-class and power-class fuses, as well as for fuse disconnecting switches and enclosed single-pole air switches are specified. These design tests, as appropriate to a particular device, include the following test types--dielectric, interrupting, load-break, making current, radio-influence, short-time current, temperature-rise, time-current, mechanical, and liquid-tightness.

This standard specifies design test requirements for high-voltage fuses (above 1000 V but also including fuses rated 601 V to 1000 V that were designed prior to 1985), distribution enclosed single-pole air switches, fuse disconnecting switches, and associated accessories, all of which are intended for use on ac distribution systems. These test requirements apply to the following equipment: a) Enclosed, open, and open-link types of distribution cutouts and fuses b) Distribution current-limiting fuses c) Distribution oil cutouts d) Distribution enclosed single-pole air switches e) Power fuses, including current-limiting types f) Fuses in enclosures g) Outdoor and indoor fuse disconnecting switches h) Fuse supports, fuse mountings, fuse hooks, and fuse links—all of the type used exclusively with products listed in a) through g) i) Removable switch blades for products listed in a) through c)