Flashcards in P2.4 Using Mains Electricity Safely and the Power of Electrical Appliances Deck (10):
Define alternating current.
Current in constantly changing direction.
What is the frequency and voltage of mains electricity in the UK?
About 230 V.
Most electrical appliances are connected to the mains using a?
Describe the structure of electrical cable.
Earth= Yellow and Green.
Neutral = Blue.
Which wire is attached to the fuse in a 3-pin plug?
Live - Brown.
What happens if an electrical fault causes too great a current?
The circuit is disconnected by a fuse or a circuit breaker in the live wire.
What happens when the current in a fuse wire exceeds the rating of the fuse?
Melt, breaking the circuit.
Some circuits are protected by residential current circuit breakers, what are they?
Operate by detecting a difference in the current between the live and neutral wires this device operates much faster than a fuse
Some appliances are double insulated what does that mean?
They have no earth wire connection.