Lightning conductors

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The general consensus seems to be that this is not a wise thing to attempt. I concur.
Does your friend live atop a barren hill? Do they really need, or simply want, one of these things? Are they aware of the downside of having one?
A conductor will attract the very strikes they seek to avoid. Which can be quite dramatic, scary in fact.
I lived in South Africa for quite some time and I must say the electrical storms around Johannesburg are spectacular, and quite dangerous to boot. Those of us that lived in houses of bricks and mortar with tiled roofs had little to fear, not so for those that chose the picturesque thatch style. Storms, and fireworks, were a worry. While little could be done to combat fireworks much was done to combat lightning.
This meant having a dirty great metal pole or two sticking up way higher than the rooftops. Rather like giant tapered flagpoles. These flagpoles were situated a metre or two from the outer walls. And they were sufficiently high that the building being protected fell within a 60 degree cone as drawn from the point of the rod.
They did work, mostly. But they draw lightning like you can't believe. With one of those things you get to see, hear and smell all the effects, real loud and real quick. The thatch dwellers had little choice as the gasses given off by wet thatch render them at risk. Your friends perhaps do have a choice.
With a lightning conductor you can be reasonably sure that you will get struck. Again and again. So I think a risk assessment might be in order because the fright you get when you do get struck is not pleasant.
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wrote:

Just wondering aloud - there is an awful lot of instantaneous power transferred when lightning makes contact. I imagine that this would fry any puny lightning conductor on the first occasion.
Presumably lightning conductors are designed such that they can carry the enormous load the instant of a second?
PoP
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Correct. I have a graph somewhere of the current flow during a lightning strike. The vertical axis is calibrated in (units of) kiloAmperes. Fortunately, the horizontal axis is calibrated in (units of) milliseconds.
Friends who have had amateur radio antennae struck have had them vanish altogether, or had to sweep up the congealed droplets of metal afterwards.
I certainly wouldn't consider installing a conductor myself. It is entirely possible to make the situation worse.
--
"The road to Paradise is through Intercourse."
The uk.transport FAQ; http://www.huge.org.uk/transport/FAQ.html
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Huge wrote:

lightening struck, it vapourised the glass fuse in his radio equipment. It didn't just melt - it simply disappeared. The noise was terrifying, and the smell wasn't great, either. My mother refused to have the antenna reinstalled.
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If a lightning conductor is struck, it has failed in its main purpose. What it is supposed to do is to cause a gradual discharge of the potential difference between earth and cloud, thus preventing a high enough charge from building up to create a strike. A proper installation has a number of air terminals, to create a brush discharge effect, and numerous conductors, to distribute the load across as wide an area as possible. While copper tape is widely used, some engineers prefer iron, because it has a higher impedance.
Colin Bignell
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On Sun, 26 Oct 2003 03:39:55 -0000, gandalf wrote:

Then there is the noise from explosive expansion of the ionised air and the stromng smell of ozone. B-)
--
Cheers snipped-for-privacy@howhill.com
Dave. pam is missing e-mail
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Thanks to you all for the very informative and interesting responses.
I had no idea there was so much involved or to be considered. Therefore I will use from stores: a No 1, Pole, Barge, Avoidance, for the use of. and recommend that my friend contacts e.g. Furse if he is really sure he needs one.
Thanks again all, I was very impressed by the level of knowledge out there and found it fascinating reading.
Dave

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Wimp! One small flash-bang-wallop!!.........
Seriously I suggest that you have a butchers in the Yellow pages. If you haven't anyone out your way then there is a firm W.Gray of somewhere in the Essex area who do travel over quite a wide area, but I still reckon that its not going to be cheap.
Perhaps you mate might like to DIY himself!..
--
Tony Sayer


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Thanks Tony,
Wimp, maybe.. but at least a non-fried wimp :)
My mate couldn't change a torch battery safely so this is sci fi league to him. He's checking with the architect who drew up the plans if he really needs a conductor, I'll pass the info on in case he does.
Thanks again.
Dave
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