1 amp, 48 volts, I would say 48 watts (round to 50 so I don’t have to use a calculator) 50 * 20 = 1000 watts of panels minimum and a 350 aH 48 volt battery minimum. Probably want a remote controlled generator too. But this is a tried and true recipe for 40 degrees north. No idea how much to upscale it for 49 degrees. Bill’s approach below will certainly get the job done. With a 2 week battery you don’t need to have as much panel.
From: Bill Prince Sent: Tuesday, March 10, 2015 5:52 PM To: [email protected] Subject: Re: [AFMUG] kWh/month and actual W load figures for new 256QAMradios I would recommend (lacking any other information) that if you're going to be running those things in a solar application that you want the highest voltage you can. Probably a 48 volt system. For an AirFiber, that is still going to be a constant 1 amp load. That's 1.2 KWH per day. At 49 north, you won't have many hours to recover, even on a sunny day. I would try to get a week's worth (Chuck would say 10 days worth) in the 2 hours of sunlight you "might" get on the winter solstice. Sooooo. That would be 1200 WH * 10 = 12,000 WH (aka 12 KWH). You need to be able to generate 6KW per hour. On my little scratch pad, that is going to be about 25 300 watt panels (best to figure about 80% efficiency on your solar panels). I shudder to think how much battery that is, and that is only one radio. bp <part15sbs{at}gmail{dot}com> On 3/10/2015 4:41 PM, Bill Prince wrote: Watts is watts. If you're drawing (for example) 50 watts. 110 VAC at ~~ .45 amps is 50 watts 48 VDC at ~~ 1 amp is 50 watts 24VDC at ~~ 2 amps is 50 watts Looking at power consumption in watts eliminates having to figure out what the voltage is. It does not deal with conversions though. The aforementioned 110VAC will surely involve some conversion efficiencies (or lack thereof). Not having any specific information, I figure at least 10% loss each time you convert. So if you're powering an AF24 on 110VAC, you can rule of thumb estimate that the real amperage (on the 110 VAC is going to be closer to .5 amps (instead of .45 mentioned above). bp <part15sbs{at}gmail{dot}com> On 3/10/2015 4:23 PM, [email protected] wrote: Looking at the mimosa b5c, AF5X and other new low cost 256QAM radios for an off grid solar application. Will be used with the tycon dc-dc poet injectors. Manufacturers, do you gave any real world figures for constant W load? Are the figures for wattage in your datasheets as measured on the AC or DC side of the POE injectors included with your radios? At latitudes above 49 north, we need to calculate very precise kilowatt hour per month figures to survive reliably through December and January.
