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?
Solution:
Schematic diagram showing common domestic circuits:
Supply from the power distribution system first goes through fuse wire then it goes to the meter which calculates electricity usage.
After passing through the meter, the wires go to distribution box which has fuses four different circuits corresponding to different loads in households.
Fuse wire is a short length thin wire generally made of tin and lead in the ratio of 3:1.
If the supply become high-voltage which exceeds the current then after reaching at a specified value of current, the fuse wire melts and breaks.
As the fuse wire melts, the circuit of the whole household breaks and thus household appliances get protected from damage.
Fuse wire comes with a current rating and they melt for any current more than that.
If we use high current rating fuse, it will allow large current and home appliances can get damaged by them.