Measured and Computed Resistance Values for Vertical Ground Rods

This paper aims to identify the causes behind the discrepancy between measured and computed steady-state ground resistance (RDC) in grounding systems comprised of vertically oriented copper rod electrodes, installed at two different sites. The RDC is measured through the Fall-of-Potential (FOP) method and is computed through simulation using CDEGS software. From the results, it revealed that the factors that contribute to the difference between the measured and computed values may be due to the gap between the grounding electrodes due to a rod coupler and the changes in surrounding soil during the driving of multiple rod electrodes. Consideration of these factors is crucial in reducing the discrepancy between the measured and computed RDC values.