This publication explains the general concepts of earthing of electrical networks and installations. It also discusses the reasons for earthing, the alternative types of earthing systems and legislation and codes of practice.

The main focus is on practical applications – how to install and maintain electrodes, and how to measure their impedance. The emphasis is on earth electrode, that part of the earthing system which is installed in the ground. General design guidance for typical earthing system is given, together with graphs, to illustrate the more important factors influencing its performance.