Skipp, A low-voltage disconnect (LVD) is normally incorporated in commercial solar charge controllers, and does not need to be purchased separately. I use SunWize solar charge controllers in my commercial repeater systems, one of which has been in service 24/7/365 since 2003, and they display a state of charge at 90% or higher on every site visit.
73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of skipp025 Sent: Sunday, January 24, 2010 11:17 AM To: [email protected] Subject: [Repeater-Builder] Re: Low Voltage Disconnect and Very Remote Site Operation > Thomas Oliver <tsoli...@...> wrote: > skipp, can you recommend a good low voltage disconnect? > tom Hi Tom, Sure... in the keep it simple world I like the Newmar units like the LVD 12-30 and LVD 12-75. http://www.newmartelecom.com/LVD-Wall-Mount/LVD-Wall-Mount.html <http://www.newmartelecom.com/LVD-Wall-Mount/LVD-Wall-Mount.html> There is also a rack mount version of the same animal and it's just the addition of a rack panel bolted to the box. I see the rack mount units being sold on Ebay fairly cheap and would buy more if I hadn't already bought/stocked a supply. Just between you and me... the only difference between the 30 and 75 amp model is the size of the internal disconnect relay (made by Bosch). And I reverse engineered both these model and they are pretty well designed (thought out) and constructed. I "try" to run a tight ship on a number of very remote location solar only sites... but even as fool-proof as I like to try and make things... I have these units protecting my battery bank(s). A few times a year some event from left field will fart off the charging system(s) and the LVD action prevents the equipment from completely draining and damaging the batteries. An interesting example of using an LVD at a very remote radio site follows: One remote site I maintain doesn't have enough solar energy or battery capacity to stay on 24/7. But the customer only needs to use the linked remote repeater during the day-time hours. So... the site uses a single 8D truck battery (very cost effective), a Newmar LVD and the fairly limited solar charging energy (panels). Each morning the remote site wakes up, the LVD allows the battery to partially recharge before reconnecting equipment. The site comes back on the air early in the morning. The solar panels charge the battery back up and run the equipment. In the evening the site operates well past sunset and goes to sleep some hours after sunset. This site has been operating as described above for a number of years... in a location where previous radio shops could not reliably keep a single repeater on the air for any length of time while keeping operations cost effective (IE keeping the Customer on the air and happy to pay the maintenance of...). During the long summer days, enough available solar charging energy (from the panels) actually keeps the repeater site on 24/7. 8D truck batteries cost me about $159 each at Sam's Club. The site only needs one battery.. So a well thought out remote site game plan doesn't have to include expensive deep cycle batteries, a lot of over-kill infrastructure costs and maintenance if you have realistic expectations of how it's supposed to behave. Since the drive in is about 4.5 hours each way we don't care to see the Bears and very full-size mountain lions living near the site (up close) more often than we have too... Last visit we only saw a number of very nice deer, a full grown fox and much later some really nasty looking eyes staring back at us (for a while) from well up the road as we drove out. I wasn't curious enough to hang around and see what it was... s. > > skipp025 wrote: > > Do you have a low voltage disconnect on the system? > > s. > > > >> "rrath" <rrath@> wrote: > >> I would like to thank all of you that > >> replied. I asked the question because > >> I thought the batteries they were bad. > >> After removing from the site, I > >> charged them both up and took them > >> to two battery shop here in Yakima. > >> The results were, they are still good. > >> So now I need to track down why the > >> system keeps going down. They are > >> 5 years old, but the repeater get very > >> little use; maybe two hrs per week > >> during the winter and about 6 hrs per > >> week during the summer. Thank you > >> all. > >> > >> Rod kc7vqr > >> > >> > > > > > > > > > > ------------------------------------ > > > > > > > > Yahoo! Groups Links > > > > > > > > > > >
