Thank you for your question regarding omni-potential grounding, it is our pleasure to help.
We have actually never seen that term in use before. “Omni-” means all or everywhere, so perhaps “omni-potential” means all-voltages? We suspect it just means that the ground system is at the same potential everywhere on your site, which is pretty much the goal of all grounding systems.
E&S Grounding Solutions uses an in-house guideline of a maximum 0.1 ohms resistance from any point on the grounding system back to the first service disconnect. We would more accurately use the term “equipotential” to describe a grounding system with an effective low-resistance path from any point within the system. “Equipotential” is also the term used by the National Electrical Code (NEC).
The NEC describes an “equipotential grounding plane” or “equipotential bonding” in Article 547.2, 682.2 and 680.26 in similar, but slightly different ways. In summary that definition is: Where wire mesh, rebar in concrete, other conductive elements, all metal structures, and fixed nonelectrical equipment that may become energized, are connected to the electrical grounding system to prevent voltage gradients from developing within the plane [E&S Grounding Solutions summarized definition].
In essence, a properly constructed equipotential grounding system would have virtually every piece of metal bonded to the grounding system. This would include things such as the rebar inside concrete foundations, building steel, columns, motor chassis, tanks, piping systems, water pipes, gas pipes, lightning protection systems, lighting poles, telecommunication & data grounding systems, conduit, cable trays, support stands, electrical cabinets, doors, gates, fence posts, fences, barbed wire, hand rails, fixtures or all types, etc.
We hope you find this answer useful. If you should have any further questions, please do not hesitate to email us again or call us at 310-318-7151, and someone will be happy to discuss your project, free of charge.
The Engineering Team at E&S Grounding Solutions
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