What principle do expulsion fuses operate on?

Expulsion fuses operate on the principle similar to that of an expulsion arrester, which is a device designed to protect electrical equipment by interrupting excessive current flow. When an overload or short circuit occurs, the fuse melts, and the resulting gas created from the arc is expelled through a vent in the fuse. This expulsion effectively extinguishes the arc and interrupts the current flow.

Understanding the operation of this device emphasizes its role in circuit protection. Just like expulsion arresters, which are used to mitigate voltage surges, expulsion fuses specialize in protecting electrical systems from overcurrent while simultaneously ensuring the safe dissipation of the arc energy. This is why the correct choice focuses on the relationship between expulsion fuses and expulsion arresters, both of which operate on the same fundamental principle of using the expulsion of gases to interrupt current flow safely.