Where should a fuse or circuit breaker be installed in a 120V AC power circuit?
In series with the hot conductor only✓Bonne réponse
In series with the hot and neutral conductors
In parallel with the hot conductor only
In parallel with the hot and neutral conductors
Explication
The protective device must interrupt the ungrounded hot conductor, because opening only the neutral would leave the equipment still connected to the hot side and energised. A fuse must also carry the load current, so it is wired in series, never in parallel.