Arc flash mitigation through the use of an engineered parallel high speed semi-conductor fuse assembly

Current-limiting fuses, in their current-limiting range, reduce the available short-circuit current and clear faults in one-half cycle or less significantly limiting the total electrical energy delivered to a fault. If the arc fault current is large enough for a current limiting fuse to be in its current limiting range, the fuse will dramatically reduce the electrical energy delivered to the arc. The use of parallel high speed semi-conductor fuses for low voltage high current applications provides greater limitation than the equivalent fault current limiting fuse rating. The engineered use of parallel high speed semi-conductor fuses can reduce the electrical energy delivered to the arc to a level low enough to obtain an Arc Flash Category 0. The use of parallel high speed semi-conductor fuses in the field requires the use of an engineered assembly. This paper details the development of such an assembly and the difficulties overcome to achieve reliable operations.