arth@cushcraft.com wrote:
>
> In many cases, a lightning strike at ground can have a peak current of
> over 35,000 amps (for a few microseconds). Imagine the size of ground
> wire required to handle this much current without melting.
>
where i work we routinely pump 35ka through a #10 wire, for a few
microseconds.
in that time there isn't enough time for the wire to heat up enough to
be
damaged. also note that the lightning shield wires on top of power
transmission
line towers is commonly 1/4" or 3/8" hs steel wire and survives
lightning
strokes that can reach 150-200ka.
--
David Robbins K1TTT (ex KY1H)
k1ttt@berkshire.net or robbins@berkshire.net
http://www.berkshire.net/~robbins/k1ttt.html
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