Installing a copper bonded earthing rod in rocky or high-resistivity soils is challenging, but there are a number of tried and tested techniques to make grounding effective with long performance. 1. Site investigation and soil resistivity testing Do a soil resistivity test (e.g., the Wenner four-pin method) prior to installation to establish the best rod length, number of rods, a... https://www.pioneerpowers.com/copper-bonded-earth-rod.php