Earthing and Fuses Prevent Fires and Shocks Flashcards
1
Q
If a fault develops in which the live somehow touches the metal case, what happens? (When case is earthed)
A
A big current flows through the live wire, the case and the earth wire
2
Q
What does this surge in current do?
A
‘Blows’ (melts) the fuse (or trips the circuit breaker) which cuts off the live supply
3
Q
What does the cutting off of the live supply do to the whole appliance?
A
Isolates it, making it impossible to get an electric shock from the case
4
Q
What does it also prevent the risk of?
A
Fire caused by the heating effect of a large current
