A high-voltage fuse is a safety device installed over a drop-out fuse to protect electrical equipment and circuits. When an overload current or short circuit occurs in the circuit, the fuse will blow and cut off the circuit to avoid dangerous situations such as equipment damage or fire. High-voltage fuses are usually used in power systems and industrial equipment. They have higher voltage ratings and can withstand larger current loads. These fuses are usually composed of insulating materials and conductive wires. When the current exceeds the rated value, the conductive wires will melt, cutting off the circuit and playing a protective role.