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From: Mark Mowery AA8TC (no email)
Date: Sat May 12 2007 - 21:31:16 EDT
> A set of battery jumper cables or a length of anchor chain with one end
> shackled to a shroud and the other dangling in the water for each upper
> shroud, fore stay and back stay during possible lightning conditions
> probably affords as much protection as any other system.
Finally! I've been waiting for someone else to say that. Now I guess I'll
jump in here too.
I attended a seminar in Chicago several years ago and had occasion to listen
to a presentation by a representative of the Polyphaser company. This
company has a huge web site. They specialize in lightning protection to
telecommunications towers. They did and continue to do extensive research in
Florida, lightning capital of the world. The presentation I attended was
highly technical: how lightning forms, "cones of protection" (not really
cone-shaped, they say), streamer formation and dissipation, etc. Lots of
charts and graphs, raw statistics, and showy Powerpoint stuff. I consumed
several Excedrin afterward.
The main thing that stuck with me is that ACCORDING TO THEM, you cannot
dissipate enough static charge through the air to make one single whit of
difference because air simply has too much electrical resistance. The best
way to dissipate static charge is through the ground (or water). Their
lightning protection schemes rely on extensive tower grounding. I don't
believe you'll find a single "bottle-brush" style lightning dissipater or
old-fashioned lightning rod (like I have on my boat, whaddaya know!)
anywhere on their web site.
Mark Mowery
Gazelle
Lake Huron
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