On Thursday, July 11, 2013 04:48:48 PM Donald Chester wrote:
> All true, but there is one other factor to consider. Because of the rapid
> rise time of a lightning pulse, it is more like RF than it is to DC or 60
> Hz a.c., so even large gauge wire copper wire or copper strap, with on
> extremely low DC resistance, does not guarantee there won't be a potential
> difference between two grounding points. The lightning pulse generates
Very true Don. Low inductance is also important in the ground system because
lightning events act more like RF than standard AC
> The lightning ground is NOT the same thing as the a.c. power safety ground.
> A perfectly satisfactory safety ground may still be a lightning hazard, and
> an excellent lightning ground might not conform to the code requirements
> for a safety ground.
This is the exactly point that many overlook when designing ground systems. I
have found that it's quite possible to invest more time and money into
designing a proper ground system than the antenna system which it supports.
Sometimes it's hard to justify the cost involved to do it properly as you are
literally pouring money into the ground. ;)
73 Bill W4WHW
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