The fuse is to prevent the circuit
The fuse is in series in the circuit, and its resistance is slightly larger than the wire, once the circuit has a short circuit,
The current is too large lead to accidents (for example, the circuit somewhere short circuit or the total power of the circuit caused by excessive current is too large)
the circuit will produce a lot of current through the fuse, the fuse will heat cut off the power to achieve the role of protection circuit to prevent the circuit
