The relationship between the Earth current and the ground resistance meter´s indication

Recently, the current (that is to say earth current) including many frequency components, flow in the soil. The earth current may influence the grounding-resistance measurement and the noise reduction effectiveness by means of grounding. In this study, authors pay attention to problem in the grounding resistance measurement and shows for a grounding-resistance measurement of the buried grounding plate that the indication of grounding-resistance meter swings in a range between some values indicated on the meter when the driving frequency, f₀, of the grounding-resistance meter has a specified relationship with an earth current frequency, and it is quantitatively shown that the grounding-resistance meter indicates the different values from the correct resistance values when the ratio of f₀ to the earth current frequency is (2m + 1):(2n + 1) (m, n: positive integer), by experiment and by calculation using the proposed model of grounding-resistance measurement systems.