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Radioguy made this statement in another topic: Lightning is a major factor in Hawaii...
It made me wonder, having seen some heavy lightning, why we do not have lightening rods required here. Especially considering that we use so much metal in our roofs.
I am not an electrician - so - any experts out there want to put forth some theories?
Mahalo
Assume the best and ask questions.
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Where would you ground it in lava? You need a good ground for your rod and I don't think we have any unless you have a lot of soil or go down to water.
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The code requires ground rods for the electrical systems at this time. My home has three. It makes me wonder, if lightning is a hazard, why lightening rods aren't required. Perhaps lightning simply isn't a factor here. There are places on the mainland where every home has one or two.
Assume the best and ask questions.
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Lightning rods on your house are a bad thing.they attract lightning and the wire cant dissipate the huge amount of energy. if you want protection a grounded flag pole away from the house will work. ( the area inside a 45deg line from the top of the pole is protected.
as for ground rods they dont trip test them here and if there not in soil whether there doing any good is up in the air.
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My house came with the most humongous television antenna I have ever seen. Fortunately, it is on the garage and not the house. I think that thing (which resembles the Sutro Tower in San Francisco) is my lightning rod.
The sun, on the other hand is my lightening rod, but I have a hairdresser who takes care of that.
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Here is a REALLY wonky explanation, but here goes.
You would think that houses with steel roofs would get hit by lightning. You would thing, more so, that sailboats with aluminum masts would get hit too. The fact is, they very very rarely do. Why?
The answer is that IF the metal roof isnt bonded to the ground, it behaves in much the same way as a Van de Graff generator. As the wind blows across the roof surface, certain quantities of electrons are literally carried away by the wind, especially with clean water in it. They are not readily recovered because the structure under the roof is typically insulating. This imparts a charge-negative-which is more like the thundercloud than the ground around the house. If you panic, like many do on sailboats, and you bond the whole thing together and to the water, you not only lose this magic forcefield but electrolyze the whole works.
Electrolysis is the single most common cause of rig failure in boats I've seen.
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whoops, reread for edit, positively meant negative--wha? Absolutely we mean positive.
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I know our solar/pv systems have lightning arrestors. Not sure if relevant to discussion
David
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JWFITZ, wouldn't that actually act more like a Faraday cage?
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OK, I know that Van de Graff does not refer to a Zeppelin, and Faraday is not a busy exposition schedule, but generator and cage don't compute with this nincompoop! Anyone care to explain?
