الفهرس 
Object of present workOnly 14 pages are availabe for public view
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Abstract
Factors affecting the earth electrode resistance and the step voltages which appear on the ground surface are studied to choose the most suitable configuration for an earth electrode in any electrical installation a thorough study of the factors influencing the soil resistivity and the different methods of measurement and analysis of soil resistivity and earth electrodes resistance as well as the size shape and depth of the earth electrodes has been made a deep electrolytic tank has beenidesigned and constructed to simulate earthing problems which enables the study of different factors influencing the effectiveness of earthing experimentally the step-voltages and their rate of change have been obtained for different earth electrodes derived expressions give the values of the steady and transient voltages appearing under unsymmetrical earth fault conditions these are evaluated using digital computers it has been shown that the positive sequence resistances capacitive reactances and the angle of faolt incidence are the most important fActors affecting the over-voltage value.