lightning and ufer

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FionaZuppa...Thanks for the link to the thread. That is impressive damage for sure.
I installed a CEE system this morning....20' #4 cu, tied to rebar, etc. It got me thinking....if the electrical equipment is struck by lightning, would it be better to NOT direct it down through the block wall and into the footing....and to use a different type of grounding electrode system?

Lightning is something I do'nt know too much about.
 

iwire

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Buck, I am not an expert here but I look at it this way.

If the lightning strike was/is so direct that it blows apart the ufer there is nothing you can do. Take away that ufer and something else is going to be damaged.


There will always be odd events, consider seat belts, more often than not they save peoples lives but sometimes they are the cause of death. You just got to go with the odds and hope for the best.

Here is some uffer info and if it was good enough to protect military ammo dumps I am good with it for a normal building. http://www.psihq.com/iread/ufergrnd.htm
 
Buck, I am not an expert here but I look at it this way.

If the lightning strike was/is so direct that it blows apart the ufer there is nothing you can do. Take away that ufer and something else is going to be damaged.


There will always be odd events, consider seat belts, more often than not they save peoples lives but sometimes they are the cause of death. You just got to go with the odds and hope for the best.

Here is some uffer info and if it was good enough to protect military ammo dumps I am good with it for a normal building. http://www.psihq.com/iread/ufergrnd.htm

Many thanks Bob for the link you provided. I remember reading this article about Mr Ufer some years ago as a result of this forum, but I've since forgotten much of the important information. You're right...there will always be odd events, especially with lightning. Thanks again.
 

FionaZuppa

Senior Member
Location
AZ
Occupation
Part Time Electrician (semi retired, old) - EE retired.
MH has a few videos discussing the pros-cons of bonding things together, and taking that bonding to the service gnd, discuses a lightning strike issue.

i would not include a building ufer for lightning arresting purposes, etc.

unless the site has a lightning arresting system there's really nothing you can do. a large bonded mesh around the site with 1,000ft radius tied to a bunch of ground rods, along with proper aerials to direct lightning strike into the earth, the earth grounded electrodes that exist at the site are vulnerable to lightning damage whether its a direct hit on the electrical service itself or just a ground strike, etc.

and just for clarity, the ufer ground electrode is not a special item that performs better because a metal rod is encased in concrete. it was a simple observation that the big wire mesh that is typically found within concrete slabs/footings can be used as an effective grounding electrode. that is, as long as the concrete is not poured over a vapor barrier, etc. many locales use or require vapor barrier for slabs.

for wet/damp locations, why tie the service egc/N to slab mesh? think about it.
 
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