A electric fuse is the safety device which is used to limit an electric current in the electric device. A electric fuse is a small conducting wire of low melting point.
The unusual high current may be due to short circuit, power fluctuation in the electric line etc. The fuse wire is made of conducting alloy or metals of low melting point. Thin wires of metals such as: tin, aluminium, copper and thin wires of alloys of bronze, brass, nichrome are used as fuse.
Fuse can be connected in series in anywhere in the circuit but in household it is connected before the main meter to protect the household circuit from higher current which may enter from the mains.
Significance: It protects the household electrical system from getting damaged due to unusual high current.
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