Causes And Mechanisms Of Hydrogen Generation Inside Fuses

Fuses play a crucial role in electrical systems, protecting equipment from overloads or short circuits by interrupting current. However, fuses can also produce gases during operation, with hydrogen (H₂) being a common byproduct. So why does H₂ gas form inside drop out fuse?

Electric Arc and Internal Reactions of the Fuse

When current flows through the metal wire or conductor of a fuse, an electric arc occurs when an overload or short circuit fault is encountered. The high temperature of the arc is sufficient to melt the metal wire, causing it to break rapidly and interrupt the current. Simultaneously, under the high temperature conditions of the arc, a chemical reaction may occur in the medium inside the fuse. These reactions lead to the generation of hydrogen gas between the metal and the medium. In particular, some special alloy materials used in fuses react with moisture in the air at high temperatures to generate hydrogen gas.

Chemical Reaction and Hydrogen Generation

The metal alloy inside the fuse may react with moisture in the air under the high temperature environment generated by the electric arc, releasing hydrogen gas. In some cases, the plastic or other dielectric materials inside a fuse can also decompose under the high temperature of an electric arc, producing hydrogen and other gases. This phenomenon is particularly pronounced under high loads or frequent current interruptions.