Lightning Rods

[Foreverford]

I have put up a tank tower with galvanized Pipe. It is about ten meters high (3 meters square) and have also put on a lightning rod on the roof. i really don't have much of an idea how the darn things work. I am going to enclose the tower in wood to create a two story house. Will the lightning rod be sufficient to keep the place safe or should I put up another lightning rod on maybe a cement post slightly away from the structure that is a few meters higher than the structure to hopefully have the hits get it instead of the one on the structure ideally. I've thought of the Lee Trevino method of putting my one iron on the top of the tower as we remember his famous quote "Heck just hold up a one iron in a storm to protect you from lightning because even god can't hit a one iron". Clueless on a Ford Forever

[Mosha]

This might help

http://en.wikipedia.org/wiki/Lightning_rod

I was taught also that the idea was to spray the atmosphere to negate the charge being built up.

[VocalNeal]

This may also help.

ERICO is a company I have seen before installed in Thailand.

I will assume that there is nothing within 100m or so that is higher, trees etc. If there is lightning will strike that first.

If there is nothing higher around you and lightning strikes are common in your area then you have more likelihood of attracting a strike than protecting against it.

[BuckarooBanzai]

I installed lightning rods above the TV antenna mast on two houses here in Surin where lightning is commonplace. I have been present at both of these houses, at different times, during thunderstorms and witnessed a lightning strike on each. The lightning pathed down to earth through the lightning rod and ground wire with no damage to houses, TV's, or anything else. Worked great. I also was taught that the lightning rod helps disperse charge differentials between the ground and atmosphere and therefore reduces the chances of a strike but as some of these thunderheads move quickly there is insufficient time for this process to work effectively and so you do get struck. I use a heavy gauge copper for the ground wire which was unaffected by the strikes. I do not see why you would need two rods for a small structure.

[BuckarooBanzai]

Just thought I would add that you need to install a ground rod as well for earthing the ground wire. I assume most already know this but just in case.

[IsaanAussie]

I remember the LT quote well. I also seem to remember he got hit once and exclaimed "Thank you God for straightening my back swing up!" or something like that.

Seriously, I watched a TV show a day or so ago that stated that Thailand suffers from 80,000 lightning strikes daily at this time of year. About 200 of those hit either houses or people. My wifes brother's house, in the middle of a group and the same wooden structure as the neighbours, got struck twice. The brother in law concerning was killed by a strike while bringing my cows home while in the paddies. A very real danger in rural Isaan and definitely not a pretty sight.

FEF, your tower should be fine if the rod is connected to the tower frame and at the base there is a "wick" connecting the frame to a copper ground stake. The issue is the concrete footing at the base of the tower is a good insulator which BB referred to. If your don't bridge the gap the concrete may explode when the tower is hit.

Shocking subject

Isaan Aussie

[David006]

Seems you ain't gonna get a definitive answer..to me lightning does not obey any perceived rules...once had a major discussion among engineers that lightening actually strikes upwards..case not proven even before the bottles were empty ..lol

There was a cow struck about 2ks from our house..it was down in the valley standing near a cellular tower...it died I think ..and they never invited me to the barbie...

[Foreverford]

Thanks all. I'm getting slower and slower by the day and probably due to ending up on my head everytime I crashed. Lee Trevino was hit twice by lightning actually. I was thinking of using a rod that was an image of him (a yuk a yukka). Again thanks for the input. The rod is on top of the peak of the metal roof at the edge of the ridge not in the middle (I don't think that will make any difference) and then has the grounding wire running down the outside of the structure to a large copper grounding rod pounded into the ground. That part seems to be standard installation (I assume) from the reading I've been doing. I guess one of my big concerns is the fact that the entire structure is iron pipe and it just seems to me the perfect conduit for the lightning but I guess the many communication and satelite towers here in the LOS have the same issues and must use a similar system for lightning.

The reason for a second rod would be to put it on a remote single pole about 20 meters away from the structure and ideally about 5 meters or so higher such that it would attract any hits and maybe keep them from even hitting the structure with the other rod on it. A bit of expense but I may not be able to get any Thai family to occupy the building otherwise as my s-i-law won't even use her cell phone in the wood house when it is storming outside. Sometimes maybe ignorance is bliss. Again thanks to all who responded as it appears that this forum has really gone quiet in regards to input from the masses. I can't believe that a previous request for some info on bananas only solicited one response but such it is. FF

[BuckarooBanzai]

Seems you ain't gonna get a definitive answer..to me lightning does not obey any perceived rules...once had a major discussion among engineers that lightening actually strikes upwards..case not proven even before the bottles were empty ..lol

There was a cow struck about 2ks from our house..it was down in the valley standing near a cellular tower...it died I think ..and they never invited me to the barbie...

Per your major discussion . . .

Multiple tower upward lightning flash captured at 9,000 images per second

http://www.youtube.com/watch?v=-bvmEYxEYiA&tracker=False&NR=1

[David006]

Seems you ain't gonna get a definitive answer..to me lightning does not obey any perceived rules...once had a major discussion among engineers that lightening actually strikes upwards..case not proven even before the bottles were empty ..lol

There was a cow struck about 2ks from our house..it was down in the valley standing near a cellular tower...it died I think ..and they never invited me to the barbie...

Per your major discussion . . .

Multiple tower upward lightning flash captured at 9,000 images per second

http://www.youtube.com/watch?v=-bvmEYxEYiA&tracker=False&NR=1

yup it's been proven ..but everybody likes to argue and drink.especially know it alls like P.Engs....lol

cheers

david