2.3 understand the uses of insulation, double insulation, earthing, fuses and circuit breakers in a range of domestic appliances

Safety precautions on appliances include:
Insulation: the covering of a live wire with a insulating material (something that won't conduct e.g plastic)
Double Insulation:

• This can be either on the live wire preventing it from touching the outer casing so no shock can be conducted that is not in the wires
• Or it can be the casing of an appliance being made an insulating material so no shock can be conduction

Earth wires: These touch the case and provide a low resistance path for the current to flow. It is attached to the outer casing and if that becomes live, the current will flow quickly down the wire and create a surge, blowing the fuse.

Fuses: These are thin pieces of wire, placed in the plug which will melt when a certain limit of current has been met. They normally melt during a surge (explained above).
Circuit breakers: A circuit breaker is an electromagnet that is turned on once a certain current limit has been reached. The electromagnet produces a magnetic field which then attracts an iron switch towards it. This opens the switch and therefore breaks the circuit.