Proper grounding proves to be an important issue when designing and installing power and lightning protection systems. The goal of any grounding system is to provide a low-impedance path for fault and lightning-induced currents to enter the earth, ensuring maximum safety from electrical system faults and lightning.
A properly installed grounding system not only helps protect buildings and equipment from damage caused by unintentional fault currents or lightning surges, but more importantly, it also protects people.
Grounding is a very complex subject. The proper installation of grounding systems requires knowledge of national and international standards, grounding conductor materials and compositions, and grounding connections and terminations. However, designers and installers of grounding systems should not overlook another important factor—soil conditions.
Below, we explore what soil resistivity is, how it is determined and the ways in which grounding systems are affected by various soil resistivity.