Grounding rings or loops

[donsoy]

We have a concept of placing ground ring or loop (bare copper conductor ranging from sizes of 4/0 to 2000 mcm) around a electrical vault to reduce step and/or touch voltage within the effective area in the vault. Do you guys have any experience on this? or any web site referances on this topic? Comments or any suggestions?

Thanks for your help

 

[busbar]

As isolated components, grounding rings or loops placed below grade around vaults or other electrical equipment do not limit touch-and-step potentials alone. Electrically and mechanically, they must be securely bonded to other local (and likely remote) ground electrodes and accessible conductive surfaces of electrical-equipment enclosures.

Two purposes are to reduce electric-shock potential and facilitate rapid operation of [overcurrent and other] protective devices associated with the equipment. [It is not a concept, but a very practical (though not always simple) procedure.] IEEE standards 80 and 837 may be applicable.