scope:

This standard specifies design test requirements for high-voltage (above 1000 V) fuses and accessories for use on ac electrical distribution systems. Devices with rated maximum voltages to 170 kV are covered. The devices to which this standard applies are as follows:

a) Expulsion fuses (including fuse cutouts)

b) Current-limiting fuses

c) Items a) and b) used in fuse-enclosure packages

d) Fuse supports of the type intended for use with fuses and fuse disconnecting switches

e) Disconnecting devices (fuse disconnecting switches, disconnecting switches, and disconnecting cutouts) created by the use of a removable fuse unit or switch blade in a fuse support

f) Expulsion, current-limiting, and combination types of external capacitor fuses used with a capacitor unit, a group of units, or capacitor banks

g) Backup current-limiting fuses ("motor-starter fuses") used in conjunction with high-voltage motor starters

h) Fuse links when used exclusively with expulsion fuses and fuse disconnecting switches

i) Items a) through f) having integral load-break means

This standard may also be used as a basis for testing other devices that are similar to the devices listed in the scope. In addition, the parts relating to expulsion fuses may, where applicable, be used for nonexpulsion fuses in which the interruption process waits for a natural current zero to clear the circuit. The manufacturer and the user should agree on any specifications or tests performed for such devices.

Purpose

This standard specifies the minimum testing requirements for fuses and related devices. Such standardization is needed to ensure uniform minimum product testing for devices within the document scope. Test areas covered are based on historical experience.