Soil surface potentials induced by Itaipu HVDC ground return current. II. Measurements

For pt.I see ibid., vol.3, no.3, p.1204-1210 (1988). A method used for the measurement of the potential curves in the soil surface is presented, together with its results, obtained at different electrode current levels (199 A, 600 A, and 2300 A). Circuits and instrumentation used are described. Information on measurement noise and on the overall precision obtained is reported. The results are presented in the form of equipotential curves.<
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