Question

Question #71cbe

Answer 1

One works by fusion and the other is a thermal + electromagnetic device.

Explanation:

The fuse, as the name says, works by fusion of a conductor, when its temperature is higher than its fusion point.
The temperature is proportional to the current, according to Joule's effect (`R*I^2`). Once it's blown, it must be replaced.

The circuit braker operates in two modes: thermal and magnetic.

When an overcurrent occurs, a bimetal heats and bends, disconnecting the circuit. The disconnection time depends of the current. The higher the current, the shorter the time.

If a short circuit happens, the magnetic coil quickly disconnects the circuit.

In both cases it can be reset and turned on again.