How about just connecting a bigger capacity battery (leisure caravan type) to the UPS in place of the 17ah ones, or wouldn't the UPS charge them?
Quote from BigFunky:
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Marine electronics use DC. No converter is needed.Quote from Banjo:
I have done this , I don't have time to get into it. Find a west marine store or like boating supply. The deep cycle batts are closed, no fumes, chargers /inverters/ converters are calibrated to cope with senstive marine electronics, rader, navigation etc. They will have an expert that can guide you thru it. The big bugaboo is as Tums mentioned, proper sine waves. Marine equipt can deal with this as the eletronics are just computers. Don't fall into the trap of gettinng cheaper RV stuff, it's not the same. If I remember, 2 older batts I replaced on baot ran 2 screens and 1 box for about 5 days, 24/7 before needed recharging. Big gel batts meant to cold start diesels tho, don't remember the amps.
Yep. That's why I said "very good inverter". That cheap Coleman junk at Wal-mart probably wouldn't work very well.Quote from Tums:
the problem is, only a few inverters produce a true sine wave...
Most of the inverters produce a "modified" square wave; depending on the quality of your electronic equipment's power supply, it might get fried by the square wave in prolonged use.
Different friend though. 