Short circuiting: When the live and neutral wires comes into direct contact, resistance becomes almost zero and current in the circuit abruptly increases. Direct contact of wires is as a result of fault in the appliance or when the insulation of wires is damged.
This is called short circuiting.
Shortcircuiting results in heating up of the line wires and may damage the appliance. It may produce spark at the place of short circuit and cause fire.
Short circuiting can be prevented by using an electric fuse in live wire.
Overloading: When a large number of high power appliances are switched on simultaneously, they draw extremely large current from the mains. If the current drawn from the mains exceeds the safety limit i.e., 5 A for domestic line and 15 A for power line, then this is known as overloading.
The appliance may get damaged as a result of over-heating of the wires. This can be avoided by using an electric fuse in live wire.
