Draw an appropriate schematic diagram showing common domestic circuits and discuss the importance of fuse. Why is it that a burnt out fuse should be replaced by another fuse of identical rating?

The diagram of domestic circuit is:

The electric power is supplied through electric poles by underground cables. In this supply, there are three wires: Live wire, insulation wire and the Earth wire. Live wire is of Red color, insulation wire is of black color and the Earth wire is of green color. At the meter board in the house, there electric wires are passed through main fuse into electric meters. Through main switch, they are connected to line wire in the house. There are two kinds of circuits used in the house which are: one is of 15A current for appliances with high power rating, the other is of 5A for low power devices. The earth wire is usually connected to metal plate deep in the Earth near the house to minimize shock due to short circuit effects. In each circuit, the different circuits can be connected across live and neutral wires. Each appliance is connected in parallel to each other so that each appliance has an equal potential difference.

An electric fuse is wire which is made of a material of high resistance and low melting point. Using an electric fuse prevents the flow of unduly high electric current and protects the appliances from the damage. Due to Joule heating, the fuse melts to break the electric circuit

A fuse with defined rating should not be replaced by the one with a higher rating because a fuse wire works due to its low melting point which is due to its rating and if a fuse with higher rating is used than it might not melt and thus failing in its purpose of using it.