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Tekart posted a really great review of his system in another thread. I was a little worried about his approach to grounding and lightning protection
Here is a couple of things to think about:
1. Try to avoid cutting off ground rods. Hitting a granite shelf? Then you are really in deep doodoo. Not because your ground rod won't go in, but because granite is a poor conductor of electricity. Areas with granite are more vulnerable to lightning damage, precisely because granite is a terrible conductor and it is hard to get a good solid ground.
If you hit rock with a ground rod, don't reach for a hacksaw! Reach for a shovel. You can bury your ground rod at an angle, but it must be full length to meet code and do a good job. The deeper the better and the wetter the soil the better. In fact you'd be better off with a #6 bare copper wire buried in a ring around your house, in granite country, than a sawed-off ground rod. And don't let the building inspector see saw marks on top of your ground rod, unless you want to incur his wrath!
2. OK, homemade lightning rods. Why? UL master label lightning protection components are *expensive*. I am playing around with this idea as well. Here is where the hacksaw might come in handy - a short ground rod section might make a pretty good lightning rod. It also makes part of a nice decoration on top of my chimney cap.
3. How many lightning rods? A UL master label lightning system would use a rod every 20-30 feet on the peak ridge of the roof. Is that guaranteed to work? No, there are no guarantees when it comes to lightning protection. But that is what the code says to do (NFPA 780, which is thankfully optional and can't be enforced by the building inspector)
--LAwrence
Here is a couple of things to think about:
1. Try to avoid cutting off ground rods. Hitting a granite shelf? Then you are really in deep doodoo. Not because your ground rod won't go in, but because granite is a poor conductor of electricity. Areas with granite are more vulnerable to lightning damage, precisely because granite is a terrible conductor and it is hard to get a good solid ground.
If you hit rock with a ground rod, don't reach for a hacksaw! Reach for a shovel. You can bury your ground rod at an angle, but it must be full length to meet code and do a good job. The deeper the better and the wetter the soil the better. In fact you'd be better off with a #6 bare copper wire buried in a ring around your house, in granite country, than a sawed-off ground rod. And don't let the building inspector see saw marks on top of your ground rod, unless you want to incur his wrath!
2. OK, homemade lightning rods. Why? UL master label lightning protection components are *expensive*. I am playing around with this idea as well. Here is where the hacksaw might come in handy - a short ground rod section might make a pretty good lightning rod. It also makes part of a nice decoration on top of my chimney cap.
3. How many lightning rods? A UL master label lightning system would use a rod every 20-30 feet on the peak ridge of the roof. Is that guaranteed to work? No, there are no guarantees when it comes to lightning protection. But that is what the code says to do (NFPA 780, which is thankfully optional and can't be enforced by the building inspector)
--LAwrence
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