Question

The diagram is Fig. 9.26 shown a three pin plug. Label the three pins.

(a) Why is the top pin thicker and longer than the other two ?

(b) Why are the pins splitted at the ends ?

Answer 1

The three pins in the plug are labelled as

Here E signifies the earth pin,

L is for live wire, and

N is for neutral wire.

(a) The earth pin is made long so that the earth connection is made first. This ensures the safety of the user because if the appliance is defective, the fuse will blow off. The earth pin is thicker so that even by mistake it cannot be inserted into the hole for the live or neutral connection of the socket.

(b) The pins are split at the end to provide the spring action so that they fit in the socket holes tightly.