Ken, This is exactly the other option we are considering. 48v (or 24v, since we already have 24v as the standard in our network) up the tower, with Transector protectors on each end, and a RSD to provide some isolation after that.
The solar consideration just came into view today, and I wanted to explore that with all due diligence before I make a final decision. At first glance it seems like the panel surface area to charge a sufficient 24v battery supply / run the gear, might make it a bit big for a standard tower install. I love this list and all the input From: Af [mailto:af-boun...@afmug.com] On Behalf Of Ken Hohhof Sent: Thursday, September 10, 2015 10:39 PM To: af@afmug.com Subject: Re: [AFMUG] a new one, I think... Or run 48 VDC up the tower and put a Mean Well RSD up there. A few years back, a WISP near here had a solar site up on a water tank. Every year they added more panels, and they never had enough. It got pretty ridiculous looking with all those solar panels hanging off the railing around the side of the tank. Granted, this is northern Illinois, not Florida. From: Paul McCall<mailto:pa...@pdmnet.net> Sent: Thursday, September 10, 2015 9:24 PM To: af@afmug.com<mailto:af@afmug.com> Subject: Re: [AFMUG] a new one, I think... Where in line to use it? We haven’t had great luck with placing those at the start of the AC path. From: Af [mailto:af-boun...@afmug.com] On Behalf Of Lewis Bergman Sent: Thursday, September 10, 2015 10:23 PM To: af@afmug.com Subject: Re: [AFMUG] a new one, I think... Why don't you use an isolation transformer? Much cheaper than solar and less tricky than hanging it on a tower. On Thu, Sep 10, 2015, 9:04 PM Paul McCall <pa...@pdmnet.net<mailto:pa...@pdmnet.net>> wrote: We charge our batteries now and a 24v array using a Samlex charger. But, that doesn’t isolate it from grid power. The charger (powered by 110) 24v output goes to the same “bus” that feeds the batteries. So, BOTH charger output and battery output are “on” at the same time. I asked here last week about a way to just run off the batteries, and no workable solution was found. From: Af [mailto:af-boun...@afmug.com<mailto:af-boun...@afmug.com>] On Behalf Of Cameron Crum Sent: Thursday, September 10, 2015 9:59 PM To: af@afmug.com<mailto:af@afmug.com> Subject: Re: [AFMUG] a new one, I think... If you are just looking for AC power isolation, then why not just a bank of batteries charged by grid power? This would isolate you from powerline surges. Cell sites have been running this way since the beginning of time. On Thu, Sep 10, 2015 at 8:38 PM, Paul McCall <pa...@pdmnet.net<mailto:pa...@pdmnet.net>> wrote: In most cases, yes we own the tower. From: Af [mailto:af-boun...@afmug.com<mailto:af-boun...@afmug.com>] On Behalf Of Lewis Bergman Sent: Thursday, September 10, 2015 9:32 PM To: af@afmug.com<mailto:af@afmug.com> Subject: Re: [AFMUG] a new one, I think... Do you own this tower? I can't imagine what I would charge someone to put a solar site on one of my towers. On Thu, Sep 10, 2015, 8:19 PM Josh Luthman <j...@imaginenetworksllc.com<mailto:j...@imaginenetworksllc.com>> wrote: If you get enough panels and batteries you'll be fine. If you cheap out and don't get enough battery run time you'll hate yourself. You're in Florida so I think with the lack of winter and a proper budget (batteries) you'll have no problems. Josh Luthman Office: 937-552-2340<tel:937-552-2340> Direct: 937-552-2343<tel:937-552-2343> 1100 Wayne St Suite 1337 Troy, OH 45373 On Thu, Sep 10, 2015 at 9:18 PM, Paul McCall <pa...@pdmnet.net<mailto:pa...@pdmnet.net>> wrote: You are correct on your calculations… my spreadsheet formula was wrong ☺ I just came up with 104 watts. I will ask the question naively.. why would you expect a headache? Isn’t solar tried and true these days? I am dealing with every aspect of surge protection I possibly can at every level already, as this summer has been a monster for us on surges. So, am doing the fiber up the tower in some cases, so I WILL have gear up there, which has its own sets of “concerns” regardless of how I power them. So, is a solar setup not reliable? The “expert” claims that he seeing it more and more in the cellular world, up the tower Paul From: Af [mailto:af-boun...@afmug.com<mailto:af-boun...@afmug.com>] On Behalf Of Josh Baird Sent: Thursday, September 10, 2015 9:10 PM To: af@afmug.com<mailto:af@afmug.com> Subject: Re: [AFMUG] a new one, I think... I would at least allow 7.5W per ePMP radio (specs say 7.5 is typical, can spike to 10), and 10-15W per 320. Maybe another 5-10w per MT radio. That would be close to 100W. You don't want to underestimate power consumption. Regarding your solar question.. I'm not sure, but that sounds like one hell of a headache. Josh On Thu, Sep 10, 2015 at 9:00 PM, Paul McCall <pa...@pdmnet.net<mailto:pa...@pdmnet.net>> wrote: OK, so I am working with a grounding expert today, getting some opinions on a couple difficult towers, and one of the first suggestions he has for me as I mention that I am looking to do fiber / DC up this tower is… “Have you considered going solar up the tower?” (to eliminate power surges completely from going up the tower) Hmmmm… So my brain starts wrestling with that… Is it practical? Say on a tower with a Netonix DC powered switch running at 48v or 24v, powering 6 ePMP APs and 2 320APs, 2 Mikrotik Bhs, and a small Mikortik router. Would be about 50 watts maximum according to my quick calcs. Not knowing anything about solar, has battery technology developed enough that it would be practical (size wise) to have enough batteries and a charge controller up in a box on a tower? And what size solar panel would I need to drive that? Paul Paul McCall, Pres. PDMNet / Florida Broadband 658 Old Dixie Highway Vero Beach, FL 32962 772-564-6800<tel:772-564-6800> office 772-473-0352<tel:772-473-0352> cell www.pdmnet.com<http://www.pdmnet.com/> pa...@pdmnet.net<mailto:pa...@pdmnet.net>
