This standard applies to external fuses used with high-voltage capacitors according to IEC 60871-1, Shunt capacitors for a.c. power systems having a rated voltage above 1 000 V – Part 1: General. IEC 60871-1 is applicable to both capacitor units and capacitor banks
intended to be used, particularly, for power-factor correction of a.c. power systems, and also to capacitors intended for use in power filter circuits.
Fuses according to this standard are intended to clear either faults inside a capacitor unit to permit continued operation of the remaining parts of the bank in which the unit is connected (unit fuses) or faults on the whole capacitor bank to isolate the bank from the system (line fuses).