What is earthing?

Earthing means connecting any non-current carrying conductor part of an electrical system with general mass of earth in such a manner that there is an immediate discharge of electrical energy to the earth in the event of electrical potential developed at that part of the system. For example, metallic frame work of electrical appliances, metallic covering of electrical cables, the earth terminal of three pin socket outlets, stay wires and also neutral point of single phase and three phase supply systems must be properly earthed. Earthing is done to ensure that no current carrying part of the system rises to be potential beyond its normal value, no non-current carrying conducting part of a system rises to a potential beyond earth potential that is zero. Proper earthing also helps to avoid electrical shock to the human beings also to avoid the chance of fire hazard due to leakage current through unwanted path.