Validation of the Calculation and Measurement Techniques of Earth Resistance Values

Abstract

Much research has been published in the literature on the mathematical approaches to obtain the most accurate earth resistance and resistivity values. However, the published research only conducted the comparisons among the mathematical/computational techniques and so far none has conducted validation tests of these mathematical/computational methods against the real earth resistance measurement at real field sites. Thus, the main contribution of this research is to show the validity of the formulas available in the literature against the measured earth resistance value at field site. The earth resistance values at three field sites for the earthing systems consists of two, three and four rods were obtained with i) calculation, where the earth resistivity is first measured, which later interpreted into 2 layers earth and used to calculate for the earth resistance and ii) measurements using a Fall-of-Potential Method. The results from this present study can help to validate the mathematical approaches in some published work against the measurement results. Also, this is the first time this kind of comparison study between the calculated and measured for two layers soil model is presented, which can help to improve the earth resistance formulas in a future, since the calculation of earth resistance is important especially at the preliminary earthing system designs.

A Simple and Safe Electrostatic Method for Managing Houseflies Emerging from Underground Pupae

“…The prerequisite for normal functioning by the apparatus was to ensure successful grounding, to pick up the negative charge from the earth's ground by the voltage generator and send it back to the ground. In the laboratory experiments, we inserted the ground-line plug of the voltage generator into the ground-contact outlet of a wall socket, which was equipped with a conductive pipe or rod physically driven into the earth to a minimum depth of 8 feet (about 2.5 m) to protect buildings against fire resulting from leakage of electricity [35]. In the greenhouse experiments, it was necessary to create an effective ground for the voltage generator because the dry surface layer of the field could increase the ground resistance (earth resistance), thereby impeding the current flow to the ground [36].…”

Experimental Study of Electromagnetic Environment in the Vicinity of High Voltage Lines

“…In literature much mathematical and experimental approaches to obtain the earth resistance values at field site were published (Nor et al, 2008).In our case the earth is considered as a perfect conductor. Then, measurements were made at two meters intervals along a direction perpendicular to the power lines, in starting from the central pylon A and when moving in an east direction to the centre of pylon C, then in an west direction to the centre of pylon B using an referenced and calibrated electromagnetic field meter PMM8053A Fig.…”

“…This justifies the choice of experimental technique with well-defined exposure conditions to determine the levels of electric and magnetic fields near power lines. Experimental characterization of low frequency electromagnetic fields has been conducted in several publications (Paraskevopoulos et al, 2009;Nor et al, 2008;Cipo et al, 2005;National Radiation Laboratory, 2005). The mastery of techniques for measuring electromagnetic fields radiated by power lines and their compatibility, at our reference center (LGEG), is a precursor to involvement in experimental research on the impact of EMF on the biological environment generally and on health particularly.…”

Soil resistivity and ground resistance for dry and wet soil

“…A practical example of ground resistance measurement has been presented in a 154 kV substation under commercial operating condition [10]. In [11], a research study has been carried out to show the validity of the formula available in the literature against the measured earth resistance values at the field site. Ref.…”