[BC] Lightning Prevention?????

[Mark Humphrey]

I agree with Mike -- I don't consider these devices a total solution, but until I see evidence that they might make matters worse by encouraging streamers to form where they otherwise wouldn't -- thus causing an *increase* in lightning strikes -- I figure they can't hurt.  And, when viewed in the context of a new tower construction or upgrade project, the additional cost isn't a major issue.  Ben Franklin is no longer with us, otherwise I would ask him for advice.
 
In any case, a low-impedance ground system and proper surge protection is essential.  At one of the sites I manage, several of the tenants decided to add to the original ground (at their expense) to meet their particular specifications.  Nextel, for instance, insisted on a Lyncole XIT rod -- which I was more than happy to approve, but I asked them to bond it to the existing ground ring with a heavy, straight conductor.  There is so much copper buried now at that site that the measured resistance is less than one ohm.  So, despite the fact that we still use a traditional rod on that tower, we haven't seen any equipment damage since upgrading from the EIA's basic grounding standard.  
 
I'm currently working on another project where we plan to use a Dialight LED beacon.  In that situation, the Nott "Eagles Nest" appears to make the most sense because this will completely surround the beacon fixture and form a type of "Faraday cage".   Anyone else using the newer Dialight product (with plastic dome) and have you had many lightning-related problems? 
 
Mark
 
 
Mike McCarthy <mre at ais.net> wrote:

I am a believer in dissipation devices to the extent that I believe 
they help de-ionize the atmosphere near the structure to some extent 
or "steer" the lighting towards them as opposed to my antennas or 
other more sensitive top of tower device(s). Mr. Whitehair's tower's 
experience should helpt bear that out.

My view is rather simple... If a dissipation array which cost me $3K to 
install saves me one major outage or antenna reapir, then it's money 
well spent...or at least we think so.

While I have no proof one way or the other, my preferred device are the 
ERI sunflowers. Heavy duty, easy to install...not too expensive.

MM


		
---------------------------------
Yahoo! Mail
 Stay connected, organized, and protected. Take the tour