Drop-out fuses and pull-load drop-out fuses are outdoor high-voltage protection appliances. It is installed on the high-voltage side of the distribution transformer or the branch line of the distribution line, and is used for short-circuit and overload protection of the transformer and the line, as well as the split and combined load current. The drop fuse is composed of two parts: an insulating bracket and a fuse tube. The static contacts are installed at both ends of the insulating bracket, and the moving contacts are installed at both ends of the fuse tube.