Fuses are simple devices that serve as protection of electrical circuits as well as equipment. Fuses are devices used for the purpose of limiting the current of a circuit, Gates A40 Hi-Power II Belts guaranteeing its interruption in case of short circuits or long overloads. The short circuit is a virtually unstressed connection between conductors under voltage or, it may also be an intentional or accidental connection between two points of a system or electrical equipment, electric motor, or a component, through a negligible impedance.

The fuse element has physical properties in such a way that its melting point is less than the melting point of copper and copper is the material most commonly used in general purpose conductors. Under these conditions, the current acquires a value that is many times higher than the operating current through a negligible transient resistance, so that the equipment and part of the installation may have a short-term or electrodynamic endurable current or thermal stress (rated current of impulse) exaggerated. Its action is due to the fusion of an element by the Joule effect, caused by the sudden elevation of current in a given circuit.