On Calculating Contact Current for Objects Insulated From the Earth and Immersed in Quasi-static Electric Fields

The shock hazard from touching a conducting object insulated from the earth and immersed in a large 50/60 Hz power line electric field is well known and has been studied in the past. The first goal of this paper is to introduce a new method based on reciprocity theory that has several advantages. It properly accounts for an electric field that is spatially nonuniform in amplitude and phase and can be used with any numerical method for solving electrostatics problems. Furthermore, calculating the contact current at a variety of different object locations and/or orientations with respect to the power line requires only one full numerical calculation and it is made clear why only the unperturbed electric field of the power line is needed. The second goal is to validate the method using a carefully conducted experiment with minimal difference between theory and experiment. With this validation, the theory can be used to characterize the accuracy of approximate methods.