Thanks you for your question regarding earthing electrode calculations, it is our pleasure to help.
The following link will give you the simplified calculation for predicting the resistance-to-ground of an electrode:
Complex electrode systems often require some very detailed calculations, particularly in complex soil conditions. E&S Grounding Solutions has the complete CDEGS software package and we would be more than happy to help you with any computer modeling services you may need. We can even help you completely via email. All that would be required is your site plans and the soil resistivity data.
If this is a service you would like, please feel free to call us 310-318-7151 California time, or simply email us back and someone will be glad to make all the arrangements with you.
The Engineering Team at E&S Grounding Solutions
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