Question

Describe domestic electric circuit with the help of a diagram.

Answer 1

$$\textbf{Concept used:}$$

The appliances in a domestic circuit are in a parallel connection

$$\textbf{Explanation:}$$

$$\bullet$$ We receive a mains supply of $$220 \ V.$$ This voltage is supplied through two wires: $$live \ wire \ (red)$$ and $$neutral \ wire \ (black)$$.

$$\bullet$$ At the meter-board in the house, these wires pass into an electricity meter through the $$main \ fuse$$.

$$\bullet$$ The distribution board supplies electricity to separate circuits within the house.

$$\bullet$$ Often, two separate circuits are used, one of $$15 \ A$$ current rating for appliances with higher power ratings such as geysers, air coolers, etc. The other circuit is of $$5 \ A$$ current rating for bulbs, fans, etc.

$$\bullet$$ The $$earth \ wire$$ having $$green$$ insulation, is usually connected to a metal plate deep in the earth near the house. This is used as a safety measure, especially for those appliances that have a metallic body, for example, electric press, toaster, etc.

$$\bullet$$ In each separate circuit, different appliances can be connected across the live and neutral wires. Each appliance has a separate switch.

$$\bullet$$ They are connected $$parallel$$ to each other so that each appliance has an equal potential difference of $$220 \ V$$ and each appliance can be operated independently.

$$\bullet$$ The use of an electric fuse prevents the electric circuit and the appliance from possible damage by stopping the flow of unduly high electric current. The Joule heating that takes place in the fuse melts it to break the electric circuit.