Fuse Boxes Explained | Electrical Safety First Fuses (may be found in place of circuit breakers) – rewirable fuses have a piece of special fuse wire running between two screws. When a fault or overload current flows through the fuse wire, it will become hot and melt. The melted fuse breaks the circuit, disconnecting the faulty circuit and keeping you safe. Getting to Know Your Fuse Box and Safety Tips | Direct Fuse Box & Circuit Breaker Safety Tips. February 20, 2019 / Written by: Vernon Trollinger. Most homeowners don’t think too much about their fuse boxes until they want to install an outlet, ceiling fan, or light fixture, or one of the fuses blows.