How is the capacity of a fuse determined?

The capacity of a fuse is primarily determined by its amp rating. The amp rating indicates the maximum amount of current that the fuse can safely carry without blowing. When the current exceeds this rating, the fuse will melt and interrupt the circuit to prevent damage to the electrical system.

While other factors like material composition, voltage rating, and physical size may influence performance or applicability in specific scenarios, they do not directly determine the fuse's capacity to carry current. The amp rating is the critical specification that dictates how much electrical load the fuse can handle in a safe manner. Understanding this fundamental aspect is essential for ensuring that the fuse is appropriate for the intended use within an electrical system.