Draw a schematic diagram of household/domestic wiring . Give its essential features.

Explanation

Figure : Schematic diagram of domestic electric circuit Its main features are :
Electricity is supplied to our homes either from overhead electric poles or underground wires through mains using two wires. One is the live wire with red insulation cover and the other is neutral wire with back insulation. The potential difference between the two is 220 volts in India .
At the meter board of the house, these two wires pass into electric meter through a main fuse. The fuse is a safety device which cuts of electricity if a high current flows through it.
Through the main switch, the live and neutral wires are connected to line wires of the house which supply electricity of different circuits. The live wire of each circuit is connected to a separate fuse so that if excess current flows, only the electricity in that part of the circuit is cut off and others are not affected.
In any part of the house, all appliances are connected in parallel to each other across the live and neutral wires. This ensures full voltage across each appliance from the mains. Each appliance is provided with a separate switch in its live wire for its operation.
Generally these circuits are divided into heating circuits- which require 15 A current and draw more power (like air conditioners, geysers, etc.) and lighting circuits - which require 5 A current and draw lesser power (like bulbs, fans, etc.)
An additional earth wire with green insulation cover is connected to devices with metal bodies such as toaster, heater, etc. as a safety measure. One end of the earth wire is connected to metal part of the device and the other end is connected to a metal plate buried deep in the ground. Any leakage current in the appliance will then be sent to the earth through earth wire.
The burnt-out fuse should be replaced by another fuse of identical rating because if a fuse of less rating is used then is blows off when normal current is flowing through it and electric appliances shall not work. If the fuse of higher rating is used in case of short circuit or overloading, the fuse would not blow up and excess amount of current may harm the appliances.