Mains Electricity
Physics: AQA GCSE Higher, topic 2.4.2
Mains Electricity
Most electrical appliances are connected to the mains using a three-core cable (a cable containing 3 wires). The wires are colour-coded. The colour tells you the wire's purpose.
Live wire is brown
- The live wire is brown and carries a 230V potential.
- It provides the alternating potential difference from the mains electricity supply.
Neutral wire is blue
- The neutral wire is blue.
- It is at or close to earth potential (which is 0V).
- It completes the circuit and carries current away from the appliance.
Earth wire has green and yellow stripes
- The earth wire has green and yellow stripes.
- It has a 0V potential and only carries a current if there is a fault.
- It is a safety wire to stop the appliance becoming live.
Test yourself on Mains Electricity
What three wires are found in cables connecting to the mains?
Which type of wire is there for safety?