Great questions … and something I should have elaborated on for sure… Yes - each portion of the tower had it’s own isolated grounds besides the tower itself. These went into a grounding grid built around the base of the site. The guy wires were of course all grounded out into their own grids as well.
The top of the tower was grounded and the bottom portion of the tower was grounded - both on separate isolated runs. The point of entry including the raceway to hold the cables were grounded - the cabling (Heliax, LMR, and ethernet) all had grounded surge suppression in that section on the building exterior. On the building interior, there was an exact replication of the outside (everything surge surpressed and grounded away from building itself). The building itself was elevated on concrete posts and two grounds for the building itself were tied to the grid as I recall. The concrete was made from a special mixture - wish I could remember the name of this stuff but it’s supposed to provide for additional protection going out to the grounding grids around the building… Each raceway, and portion of the lineups were tied into an interior grounding block which was then ran outside. This is all by memory …. It was literally at $2mil site with equipment and tower. There was a company brought in for the engineering aspects and another company specific to the grounding portions. Thanks, Paul > On Aug 16, 2017, at 10:21 AM, Chuck McCown <[email protected]> wrote: > > So, was the tower mounted equipment isolated with its own ground wire? > Curious about the improper isolation at the entry point. > What was the proper way and what did the improper installation do to violate > that? > > From: Paul Stewart <> > Sent: Wednesday, August 16, 2017 8:05 AM > To: [email protected] <> > Subject: Re: [AFMUG] how far and much > > I’ve only ever encountered one tower (at former job) that was pretty > “bulletproof” … > > The tower was 350ft and located on the highest elevation for about 100 square > KM area … so it was a prime target for lightning strikes. I don’t know > exactly how many times a year it took a hit but would guess at 8-10 times per > year it would have a direct hit. There was only one time where any damage > occurred and it was because of some shoddy updates by a 3rd party contractor > whom didn’t do proper isolation at an entry point (effectively bypassing some > layers of protection). > > That site had a full cellular deployment along with several PTP600’s for > backhaul and PMP320/PMP100 - with the cellular being at the very top and the > Cambium gear further down. > > Paul > > >> On Aug 16, 2017, at 9:11 AM, Eric Muehleisen <[email protected] <>> wrote: >> >> No such thing as a bullet proof tower. At least not in my area. All the >> over-engineering in the world can't stop a direct strike. Some days you get >> lucky, some days not. It's a roll of the dice. >> >> On Wed, Aug 16, 2017 at 7:29 AM, David Milholen <[email protected] <>> >> wrote: >>> I am asking for pure simple curiosity. >>> How far would you go and how much would you spend to have a bullet proof >>> Tower site? >>> I am looking for answers in small class tower to super duty types or leases. >>> What I mean by bullet proof is How many time a year are you replacing gear >>> due to weather complications >>> or how many times are you going to back to the site to reboot something . >>> How many times are you remoting into a >>> site to adj power or channels to avoid interference. How many times are you >>> having to make adjustments to ethernet ports. >>> All these tasks add up in time. >>> Our team this year has only had to visit 2 sites unexpectedly due to >>> weather and take the next step in making it bullet proof. >>> >>> >>> -- >>> <Davidmvcf.jpg> >> >> > >
