A new method to increase the effective length of horizontal earth electrodes

In this paper, field experiments and computer simulations of a sectionalised 88 m length horizontal earth electrode under different energisations (dc, variable frequency ac and transients of different shapes) are reported. From measurements of the voltage and current at the injection point, and by incrementally increasing the length of the test electrode, the effective length of the horizontal earth electrode was determined under the different energisations for the soil conditions pertaining to this particular installation. The experimental and simulation results of voltage and current show reasonably close agreement, and it is demonstrated that satisfactory prediction of the effective length using simplified formulae is achievable. A new method to increase electrode effective length is proposed.