Selection Guidelines For Fuses In High-altitude Environments

At high altitudes, the decrease in air pressure and air density significantly alters drop out fuse working environment. Thinner air reduces heat dissipation efficiency, leading to increased internal fuse temperatures. For every 100 meters of altitude increase, the fuse temperature rises by approximately 0.1–0.5 K.

The decrease in ambient temperature does not necessarily completely offset the temperature rise caused by poor heat dissipation, especially in poorly ventilated or enclosed environments such as equipment enclosures. In such cases, the thermal load and electrical insulation conditions borne by the fuse tube and insulating support change.

Compared to ordinary fuses, these products designed for high-altitude environments are optimized for heat dissipation, insulation, and arc extinguishing performance, making them more suitable for long-term operation in thin air and low-pressure environments. This design takes into account the difficulties in arc extinguishing caused by low air density and adjusts the fuse tube's materials and structure to resist potential risks from electric arcs and overheating.