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Jon Elson[_3_]

wrote:

If you get a 100,000 ampere lightning strike directly to anything
other than a metal building, the V=IR (voltage = current x resistance)
drop is going to raise the voltage of everything tied together many
many volts. All you can do is try to keep everything at the same
(elevated) voltage to avoid killing people/animals. This is done by
tying everything to the same local internal "ground".
This is a fantasy, unless you have 1/4 " x 3" bus bars running the
length of your house, and from the main service panel to the ground
field, which would be maybe half an acre of bare welding cable
buried in the earth.

Otherwise, you simply can't get a low enough impedance to keep
the IR drop anywhere within reason. And, the induced voltages across
various points such as plumbing and plugged-in appliances can
be lethal. (later part of your post seems to agree with this.)

So, mostly, you want to try to conduct lightning strike currents
away from the building, not THROUGH the building. So, what I have
is a ground rod driven directly under the antenna, and connected
to the mast via 4 gauge cable. If the lightning current goes through
the house, it can easily set it on fire.

Jon