Under line to ground fault conditions, the available Ground Potential Rise (GPR) on a grounding system and resulting Step/Touch voltages must be within safe and tolerable levels. These voltages are calculated using grounding system design software. Field measurements are taken for soil electrical resistivity to use as input for the design software used in these calculations.
This project provides a tool, in a spreadsheet table form, to predict GPR and Step/Touch safety conditions knowing the approximate design dimensions of a new grounding system to be installed. This spreadsheet is intended to be a high level “first cut” interpretation of safety conditions to be used in the field with soil electrical resistivity test results to determine how safe a particular ground grid design will be in the measured soil conditions. It does not represent a final design of the grounding system.
Grounding, Ground Potential Rise, GPR, Step Voltage, Touch Voltage, Substation