Ground Resistance Measurement With Alternative Fall-of-Potential Method

Abstract

An alternative fall-of-potential method is presented to measure on-line and in situ resistance of ground electrode systems in low-voltage distribution networks. It provides simultaneous resistance measurements of both equivalent ground electrode system of a substation and ground electrode of a premise. The method does not require usage of any auxiliary electrode, but employs two existing ground electrodes in the distribution network. The method has the advantage that it uses moderately high currents than the classical fall-of-potential method, and results are independent of test electrode positions. The method is especially useful in urbanized districts where it is difficult to apply the classical fall-of-potential method. Also, a capacitive potential probe was successfully tested in place of the current electrode used in the fall-of-potential method.