power sytem for travel trailer

I'm trying to put together a power system for a travel trailer.

Basically, I need a battery charger/inverter that takes 120 volts input and provides 12 volts output as well as keeping a 12V deep cycle battery charged. This allows the 12V lighting and 12V appliances to operate whether or not the the trailer is plugged into AC power. I was looking at this:

www.mccampingsupplies.com...


But; I also need to add a twist to the equation. When the trailer is away from AC power for an extended time, I want a 100 watt solar panel to recharge the battery thru a charge controller. I wrote one company and asked them if I could add a solar panel/charge controller in tandem with the iota charger/inverter but I did not receive a reply.

So ..... how can I make this idea work? Any suggestions for make/model/vendor of equipment that will fulfill my requirements? Any ideas really appreciated......

ok - first off IMHO that powersupply looks quite expensive for what it does - yes it is very hi spec - but the way i read it its really designed for several days ` on grid ` / a couple days off grid use .

to acheive what you want - i would go with virtually independant circuits

curcuit one - external AC > inverter > batterycharger

circuit two - sollar panel > battery charger

and have a manually switched issolator - so that you can draw appliance power from either the battery bank OR the invertor output

because you are never going to have both the inverter and solar panel in use simeltaneously

reply to post by rko_radio


I currently live in a small RV trailer and unless you're full time off grid, there's no way you can have enought battery and charging capacity built in to sustain more than a few electrical devices with a 100 watt panel for very long. 3-500 watts maybe but not 100 watts. With a lack of space, you might be able to pack enough battery to power 8 amps for a day with out recharging but that's about it. You'll need either a gas/diesel generator or wind charger to back up your PV cell(s).

I have direct power to my lights and fans, and 4 cigarette ligher style plugs. Inverters eat into you efficiency which doesn't help your limited storage capacity. For refrigeration, I use a 5-day cooler inside another well insulated box that has heat reflective roof coating on the outside. I use big blocks of ice in water tight containers and not loose ice. With normal daily use, my ice box will stay at 45 degrees even on the hottest of summer days. It will take about a week of normal use in the summer to complete melt the blocks in the cooler. One of these very small 12v freezers can re-freeze one of my blocks in about a day, so I just cycle the blocks through once a day. Your fridge is your biggest power draw and your most necessary after your lights and radio. Everything else is just luxury.

reply to post by crgintx


Hey, thats a great idea! I'm going to start doing that. I gotta make a good effiecent icebox first though. So you just freeze a new block about once a week and replace the one thats melting away right? I've heard of that being done on boats but it never hit me for whatever reason to try it on a trailer/RV.

BTW, theres a website, fiberglassrv.com I think its called, that has a forum w/ a section on DIY projects for trailers/RVs. I bet they could help.

[edit on 9-4-2009 by JJRichey]