Lightning arresters
Lightning arresters
(OP)
What type of lightning arrester would you recommend to be installed at the roof deck of a 12-storey commercial buliding?
encon5
encon5
When was the last time you drove down the highway without seeing a commercial truck hauling goods?
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RE: Lightning arresters
RE: Lightning arresters
Two floors of the building are being used as school for computer sciences courses and installed in those floors called computer labs are 300 units of PCs with servers and routers. Thunderstorm is prevalent in the area hence we want to protect the computers as well as other electrical equipment installed.
Is this enough info? Again thanks
encon5
RE: Lightning arresters
Don Phillips
http://worthingtonengineering.com
RE: Lightning arresters
RE: Lightning arresters
A good source of information is from one of the manufacturers of lightning protection equipment and systems. Thompson Lightining Protection Inc, (www.tlpinc.com) has a very good design guide and equipment descriptions and specifications. You need to consider especially for your voice/data systems that it is critical to provide as much isolation from the system's equipment, power sources and grounding system as possible. Extreme care with regards to the building steel in routing of the downleads from the lightning arrestors is also critical. Hope you get enough information to help.
Good luck,
RE: Lightning arresters
Ricardo
RE: Lightning arresters
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this is your protection zone. and entire building needs to be inside cone made when you rotate this thing up. If you can not put high spike pole you can chose to put 4 on corners their height should suffice to get the same principle on roof surface (you can put 5th in middle also )
Lets not try to make science from lightning protection :)
(My professor words and he was doing researches on lightning protection for 20 years) This simple solution and calculus is still the best protection for 99% of purposes. (I am protecting gas power plants on exact same basis)
RE: Lightning arresters
"Lightning arrestor" is the wrong term for what you want -- an arrestor is more akin to the surge suppressor you plug your computer into than a lightning rod, something to "drain" spikes off the power lines to ground. You'll just confuse people asking to put the arrestor on the roof, when everybody knows that arrestors belong inside your switchgear or on your power pole.
For a lightning protection system, most on this site (including me) would recommend an old-school Franklin type rod designed and installed per NFPA 780 as previously mentioned. Copper is usually the material of choice, unless you have a lot of aluminum on your roof (HVAC equipment, etc), then in that case you'd probably want aluminum.
There's also a new-fangled type that look like Christmas ornaments, known as "early stream emittors" (ESE's) or some such. Most engineers would probably recommend you stay away from those. See http://www.straightdope.com/columns/010824.html for more on ESE's, including a brief struggle to get a new NFPA 781 adopted. So far as I know, NFPA still does not recognize ESE's.
PS -- you can see NFPA 780 for free (along with all other NFPA codes) at h
RE: Lightning arresters
RE: Lightning arresters
I don't know much about how the Brits do lightning protection. But the few installations that I've seen, they seem to use something more like flat iron straps run flat along the roof and welded together into sort of a mesh. No vertical elements at all.
Us Americans would all just wave our NFPA 780 books at you and tell you how silly that was, we've known ever since Ben Franklins time that you need a vertical rod. But at least your neighbors wouldn't laugh at you if you put one of those strap systems on -- at least not until your house got hit by lightning just after you got done installing it.