or smog cover. ;-) There's more usable sunlight here in Chicago than there is in LA and they're a bit south of us.
----- Mike Hammett Intelligent Computing Solutions http://www.ics-il.com -------------------------------------------------- From: "Christopher Erickson" <christopher.k.erick...@gmail.com> Sent: Friday, January 15, 2010 1:21 PM To: "'WISPA General List'" <wireless@wispa.org> Subject: Re: [WISPA] Solar suggestion for ultra low use site? > Latitude and average cloud cover will be factors. > > I would use MorningStar MPPT solar charge controllers. Get every > last watt of solar charging you can manage. Each controller can > handle one to three 75 to 200 watt panels. If you end up needing > more than three panels, add controllers and panels until > sufficient charging is obtained. > > Avoid as many power conversions as possible. Power conversions > never have 100% efficiency and many of your precious watts end up > wasted as heat. > > 6V golf cart batteries are the best bang for the battery buck and > can be deep cycled much better than 12V automotive-style batteries > because they have much thicker plates. > > Dusty and/or snowy areas can be a problem. If so, schedule > regular PMI visits to inspect and clean the panels. > > Use security screws on the solar panel mounting brackets. Solar > panels are starting to become a popular theft item. > > "My advice is free and worth every penny!" > > -Christopher Erickson > Network Design Engineer > Waikoloa Village, HI 96738 > N19°57' W155°47' > > > >> -----Original Message----- >> From: wireless-boun...@wispa.org >> [mailto:wireless-boun...@wispa.org] On Behalf Of AJ >> Sent: Friday, January 15, 2010 8:38 AM >> To: WISPA General List >> Subject: [WISPA] Solar suggestion for ultra low use site? >> >> Thought I'd tap in to the collective intelligence of the WISP >> group for this >> question... >> >> >> Looking at setting up a solar powered VHF ham repeater in the >> middle of a >> metro area for infill coverage... Site is land locked by >> ghetto on one side >> and rail tracks on the other - commercial power is not an option. >> >> We have available a dozen or so surplus Alpha 85 amp hour gel >> cell batteries >> which test out at roughly 90% capacity (PM swaps)... >> >> The first thought was to simply charge up a battery for each >> event we work >> in the downtown core, drop by the site and swap out whatever >> battery is in >> place.. Not quite the most efficient plan. >> >> Our next thought was to place a decent sized array, maybe >> 300-400 amp hour, >> then supplement with an off the shelf solar panel or two to maintain a >> charge... >> >> Our equipment consists of an ancient GE MastrII repeater >> turned down to 25 >> watts and an NHRC controller. Standby draw is 125 mA, >> transmit ramps up to >> about 3.5 amps... >> >> Duty cycle is key here - we work perhaps a dozen events a >> year within the >> coverage of this repeater for about 4 hours each on about a >> 10% duty cycle >> (TX 6 out of every 60 minutes). The rest of the time the >> repeater sits idle >> and will not transmit unnecessarily (no IDs or anything >> unless it's actively >> in use)... >> >> What is out there on the market for a low cost solar site? >> >> Thanks! >> -AJ >> >> >> -------------------------------------------------------------- >> ------------------ >> WISPA Wants You! Join today! >> http://signup.wispa.org/ >> -------------------------------------------------------------- >> ------------------ >> >> WISPA Wireless List: wireless@wispa.org >> >> Subscribe/Unsubscribe: >> http://lists.wispa.org/mailman/listinfo/wireless >> >> Archives: http://lists.wispa.org/pipermail/wireless/ >> > > > > -------------------------------------------------------------------------------- > WISPA Wants You! Join today! > http://signup.wispa.org/ > -------------------------------------------------------------------------------- > > WISPA Wireless List: wireless@wispa.org > > Subscribe/Unsubscribe: > http://lists.wispa.org/mailman/listinfo/wireless > > Archives: http://lists.wispa.org/pipermail/wireless/ > -------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
