Down here, the Electric Utility (Austin Energy), is faced with rock
(limestone) down about 18 inches in Western part of city. They did some
modeling and experiments, and determined an effective Electric Utility
standard ground could be provided by burying no. 10 copper wire that deep,
and 200 foot circumference around a building or sub station as a perimeter
ground. All electrical ground wires go to that, and it is as effective as
the three rod types of grounds. Useful to know where driven rods bend and
stop 3 feet short of going all the way to earth.
73, Stuart K5KVH
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