What other types of grounding electrodes are there apart from ground rods?
What other types of grounding electrodes are there apart from ground rods? Grounding Plates Grounding plates are typically thin copper plates buried in direct contact with the earth. The National Electrical Code requires that ground plates have at least 2 ft2 of surface area exposed to the surrounding soil. Ferrous materials must be at least 0.20 inches thick, while non-ferrous materials (copper) need only be 0.060 inches thick. Grounding plates are typically placed under poles or supplementing buried ground rings. Grounding plates should be buried at least 30 inches below grade level. While the surface area of grounding plates is greatly increased over that of a driven rod, the zone of influence is relatively small as shown in “B”. The zone of influence of a grounding plate can be as small as 17 inches. This ultra-small zone of influence typically causes grounding plates to have a higher resistance reading than other electrodes of the same mass. Si...