Soil properties, GPS, arcview, and soil resistivity provide tools for protecting electrical equipment from lightning and heat

Resistivity measurements determine the number of chemically enhanced grounding rods needed to provide protection from lightning strikes and mechanical heating of electrical equipment. Soil physical properties such as texture, rock content, soil thickness, and water content determine resistivity and grounding potential. A study was initiated to (1) establish a database of electrical resistivity properties for several soil series in southwest Missouri, (2) correlate several soil properties to electrical resistivity, and (3) gather data to aid in determining the number of enhanced grounding rods needed at each site with electrical equipment. Recommendations made regarding installation of grounding rods have resulted in protection of electrical equipment at all sites.