Earthing is a safety device used to prevent a shock due to leakages arising from weak insulation, breaking of the element or otherwise. The metal bodies of appliances handled like the electric iron, kettle or refrigerator must be earthed, that is, connected to a pipe leading deep into the earth on to a metal plate. In case the metal body becomes live, the circuit is completed through the live wire and the earth, resulting in a high current. The fuse on the live-wire side should blow out immediately, and the matter should be investigated and the fault rectified. In case the fuse does not blow out, and a person touches it, a severe shock is still prevented. This is because most of the current flows directly to the earth via the earth connection which has negligible resistance. An extremely small current, if at all, may pass through the person’s body which offers a resistance, resulting in only a mild shock
The process of transferring the immediate discharge of the electrical energy directly to the earth by the help of the low resistance wire is known as the electrical earthing. The electrical earthing is done by connecting the non-current carrying part of the equipment or neutral of supply system to the ground.