[TowerTalk] lightning protection

[Dan Zimmerman N3OX]

>
> but unless your shack is
> absolutely properly engineered, you will still have damage from a strike,
> perhaps far worse than with disconnection.


If you don't drag your cables far outside, or have them grounded to a good
bulkhead at the house that's bonded to the rest of your system, you risk
burning your house down with disconnection.

20kA traveling through a 6AWG or 2AWG wire  for a few tens of milliseconds
will not cause enough heat to light anything on fire.

20kA traveling through a 3 foot arc to the nearest grounded thing on/in your
home for a few tens of milliseconds certainly will.

So you're not just protecting your ham gear.

K5MO says:

"There was induced voltage enough to leave  a large black zorch from mark
the (floating) plastic
enclosure the coax ends were in, about 1' to the heavily grounded metal
bulkhead  near the
house, which apparently conducted the energy to ground."

Which it would have happily done without involving an arc as hot as the
surface of the sun if the cables had still been plugged into it.

Just something to think about.  Sounds like your arc and zorch was on the
outside of the house, but ...

73
Dan