My 2 cents. Never assume ANYTHING about existing ground at the tower, at the shelter, at the service panel. Measure everything. If you get a sub-Ohm measurement you are tied into a loop which may or MAY NOT actually be “effectually” grounded. Remember that CADWelds can break with a strong enough strike, so a ground ring around in or outside of a shelter may indeed have poor grounds to the actual earth. We put in inspection boxes (sprinkler boxes) at every connection point to be able to come back later and test.
50% of the commercial towers we tested had at least one leg of their tower grounds be under spec. For us, (and the cell guys) spec is <5ohm, but if all points were at 8 ohm I wouldn’t freak out. More than 50% of the electrical panels we pull from had poor ground. We either forced the tower companies to fix the problem or if they didn’t, magically it would get fixed in the middle of the night. Pays BIG dividends in Florida. From: Af [mailto:[email protected]] On Behalf Of Justin Wilson Sent: Friday, December 2, 2016 1:21 PM To: [email protected] Subject: Re: [AFMUG] CAT5e/6 tower grounding http://wirelessestimator.com/content/standards/eia_tia_222/protective-grounding-standard this is a good start. https://sites.auburn.edu/admin/facilities/spw-bid-calendar/11-150%20AU%20Regional%20Airport-Construct%20a%20Self-Supporting%20Radio%20Tower/Project%20Documents/1/Motorola_R56_2005_manual.pdf Justin Wilson [email protected]<mailto:[email protected]> --- http://www.mtin.net Owner/CEO xISP Solutions- Consulting – Data Centers - Bandwidth http://www.midwest-ix.com COO/Chairman Internet Exchange - Peering - Distributed Fabric On Nov 22, 2016, at 7:54 PM, Dev <[email protected]<mailto:[email protected]>> wrote: I’ve heard it’s good to ground multiple places, like up by the radio, down by the turn to the ice bridge and inside the shelter, but how do you that (and is it necessary) with CAT5e/6? Do you strip a section off the insulation and tie the drain wire to multiple ground lugs? Sounds hard to do and not get water in the cable. I just have been running surge suppressors inside the building that the cable plugs into before heading to the switches/etc. What should I be doing?
