RV's all contain power supplies that are designed to use 120 volts from either generator or park power, to provide fifty-sixty-ish DC amperage to the 12 volt (13.8) rails and "house" batteries around the RV. RV's run a LOT of stuff on 13.8: fridge controls, Air Cond. controls, fans, furnace, lights, alarms, water pump, etc. The difference between these power supplies and an automotive changer, is that the RV supplies are designed to work with a deep cycle battery (often a pair of 6V T105's in series) floating on the 12 volt rail, and have the 14.4 v bulk charge, 13.6 v maintenance or "absorbtion" charge and 13.2 float settings logic built in. The power supplies are also designed to provide up to charger max current rating to the 12 volt rail once battery(s) are charged. Typical power supply size for a pair of T105's is 55 or 65 amps, which will nicely power a station with a pair of K3's plus a lot of 12v accessories. T105's are more commonly known as pro golf cart batteries, with six in series a typical battery array in a golf cart.
The power supply has to match the house batteries' rated max sustained charge current. When "house" 12v draw plus battery charge current exceeds the rated current, the power supply voltage drops to limit the current at the rated amperage. This is what I have in my RV. Camping World prices for these units can be beaten on the internet. http://www.campingworld.com/shopping/item/wf-9800-series-converter-charger-55-amp/58324 My RV is a self-contained field day station that can put everything on the 12 volt rail.The generator or park power runs the microwave, the air conditioning and the aforementioned RV 12v supply. The T105 house batteries could easily handle a 2 x QRP entry for the 24 hours. Using this kind of power supply at home to run a battery float system is very easy, once the venting and safe location of batteries issue is settled. The batteries and power supply can be quite a distance from the shack if single aught copper is used to bus the current from battery to shack and distribution/fuse device. 73, Guy. > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
