Drop-out fuse selection by Operating Voltage select the following criteria:
1, for the current-limiting fuse to fuse quartz sand as a filler current-limiting fuses can only choose Ue = Uwe conditions, the maximum overvoltage multiple in this case produced such a blown fuse specified limits 2.5 times the phase voltage within this value does not exceed the same voltage level of electrical insulation level. If the fuse used in the operating voltage is below the rated voltage of the grid, over-voltage multiple threat is likely to increase from 3.5 to 4.
2, the general condition Ue≥Uwe formula: Ue-- fuse rated voltage Uwe-- installed at the rated voltage grid that is fuse rated voltage (kV) should not be less than the fuse is installed at the rated voltage grid (kV).