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#55244 08/21/05 01:36 PM
Joined: Jun 2004
Posts: 176
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Anybody here ever been struck, or been close to being struck by lightning?

When I was 13, I was watching a thunderstorm out my front window. I saw lightning hit a phone pole a few blocks away, and at the same time, I thought to myself "why does it feel like i'm falling backwards?" I was on the floor for a few seconds before I got up, when I felt my brother searching for a pulse. He told me that a spark jumped from the radiator to my knee. I remember not being able to move my legs to keep myself from falling. I wasn't scared until after I knew what happened. I'm just glad that it wasn't full force.

#55245 08/21/05 02:08 PM
Joined: Jul 2004
Posts: 9,923
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In Florida lightning is a regular thing. I have had it popping around me lots of times. The most exciting is when it blows the top out of a nearby tree and you are showered with little sticks, on fire at both ends.
It hit the 125kv tower behind my boat dock this spring and lit the place up with an eerie blue for what seemed to be minutes but I have to believe it was only a few milliseconds. The image was still burned in your eyes for a while.

There are plenty of opportunities to sell lightning protection tho.


Greg Fretwell
#55246 08/21/05 04:09 PM
Joined: May 2002
Posts: 1,716
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I was born and raised (34 years) on lightning alley, (central FL) and growing up I remember my parents house was hit only once, and none of the other houses I lived in were ever hit.

Moved to N.C., bought a two story log house built in 1939. The first 9 years we lived here the house suffered lightning damage 7 times from either direct hits, or trees being hit within 50 feet of the house.

Once it came in on the phone lines (buried) and vaporized every phone conductor in the home, this came closer to causing a fire than any of the other times, although there was always damage.

I had the opportunity to talk to an gentleman who had lived here in the late 40's to early 50's as a teen, and he informed me the house was hit a few times when he lived here.

The area the house is built on is pretty much a sheet of mica (as in insulator) which I suspect has some bearing why this is such a hot spot.

I had sworn that I would add a ground ring around the house to help the poor lowly rods each time, but have never gotten around to doing it, and with the mica considered, I question if this may in fact be more of a path back into the structure.

I removed the tin roof (not for this reason though) and primitive lighting rods after the 5th time and don't know for sure if this had anything to do with the reduction in the frequency of events, but for the last 4 years we have not been hit. (knock on wood)

I do remember a story which I think is true, I don't remember the exact details though.

It seems as though it had to do with two brothers in FL that were killed by lightning within a few feet of each other at different times (years apart I believe) when I was growing up.

Anyways, I have a great respect for it.

Roger

[This message has been edited by Roger (edited 08-21-2005).]

#55247 08/21/05 08:46 PM
Joined: Dec 2001
Posts: 300
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It was an exceptionally hot summer day and I was tired and dirty from work.

I decided to get a cool bath. I was in the tub and saw the dark clouds rolling across the fields toward us and knew this was going to be a bad storm. Figured I had better get out of the tub. Then I felt it.

A little tingle through the tub drain cover plate as I saw a strike a mile or so away. So being the smart guy I am, I figured the voltage was discharged and I was safe so I stayed in the tub to watch the storm.

It turns out that the guy who said "lightining never strikes the same place twice" was a liar. A few minutes later, my wife saw the lightning strike a telephone pole about 1/4 mile down the road, and saw the flash come down the pole directly in front of our house.

I felt it bad. I jumped from the tub and screamed like a little girl. Took about 30 gallons of water onto the bathroom floor with me. I ran into the living room naked screaming that I had been struck by lightning.

After being struck, I tried all the standard super powers: flying, invisibility, x-ray vision...nothing.

#55248 08/21/05 09:01 PM
Joined: Jul 2004
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Sorta makes you want to go and tighten up all your ground/bonding clamps huh?

[Linked Image]


Greg Fretwell
#55249 08/22/05 06:40 AM
Joined: May 2001
Posts: 717
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Roger,
I taught a "Grounding and Bonding" class for apprentices for a long time. Someone talked me into opening it up to all a long time ago.

One of the first classes open to all, was strangely full of communications engineers from the local phone company, which has since been sucked up by GTE. We had some fine arguments until ya put the math up on the board and they said, "Wow, this guy has a point"

Their own installation manuals said to connect all grounds to electrical service grounds. They were in the habit of simply driving their own 4' ground rods and calling it done, setting up a capacitor in the structure AS A LIGHTNING ATTRACTANT!

I found out why they were all there from a friend of mine that worked for them and 'slipped' me the manual. The separate grounding system also caused a lot of induced voltage problems on their equipment from proximity to the overhead power lines.

Since your problem is coming from the comm, suggest you take a #6 from the Network Interface Device (or whatever they use for such, especially if it is a carbon block) to your service ground.

BTW, I have a pretty extensive grounding system at my house, and a #6 to the NID from the ring. I've argued with several of their installers over the years about this, usually let 'em take it off to make them happy, and put it back when their tail lights disappear.

Be willing to bet it would help a bunch. If you've already done it, check your rods and their connections. I switched to cadwelds a long time ago, check Erico's web site for some independent testing documents, you'll be convinced.

[This message has been edited by George Corron (edited 08-22-2005).]

#55250 08/22/05 09:50 AM
Joined: May 2002
Posts: 1,716
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Member
Good morning George, the phone system is tied to my service grounding and was only affected once out of the times we have been hit, so I don't think that is necessarily a major player.

As I said in my earlier post, I have had trees get hit, two Poplars on two different occasions about 50'-60' from the house (actually saw one get hit) and then run into the house, I assume through the GE.(rods) On both of these occasions it took out the lower water heater element, and tripped individual branch circuit breakers.

On one of the other occasions, the fuse was nailed on the pole mounted transformer.

Taking into consideration the mica that is underground, what I question is, does the charge travel above this sheet insulator and find it's way to the MGN via my GES.


Roger



[This message has been edited by Roger (edited 08-22-2005).]

#55251 08/22/05 01:08 PM
Joined: Jul 2004
Posts: 9,923
Likes: 32
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When you are protecting equipment inside a building, bonding is more important than grounding. There is always going to be a significant voltage spike. The objective is to make everything ride that wave in unison. Your house becomes a helicopter lineman for a few miliseconds.
That is one reason why the Ufer works so well, even when the building is floating on a bed of dry sand.


Greg Fretwell
#55252 08/22/05 08:11 PM
Joined: Feb 2002
Posts: 2,233
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I came close to being hit by lightning, twice. Once I was walking into work when WHAM! A lightning bole and followed by the loudest clap of thunder I ever heard. I said to my self. Gee that was a close hit. I went into work and all the lights were out. That is when I found out that the pole outside that I just walked past was hit. Another time a tree on my property about 75' from the house was hit. It burnt out a modem, several light bulbs and lots of dimmers.


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