In previous sections, we talked about what an earthing system is and what it does. Now we are going to list down some of the most important purposes for which earthing is in service. Electrical circuits are connected to the earth or indeed to the ground for some reason. Below are several reasons why it is important to use a grounding system.
Personal Security
Protection of the electrical system
Protection of electromagnetic pulses
lightning protection
A sufficiently low impedance to facilitate satisfactory safety operation under fault conditions.
Overvoltage protection, within reasonable range under fault condition
Graded insulation in power transformers.
Limit voltage to earth on the conductive material enclosing the electrical conductor or equipment.