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rodwha's avatar
rodwha
Explorer
Nov 15, 2016

Understanding Power

I've been reading up on power needs and uses, but things aren't quite clear.

For starters I'm looking at the Keystone Passport 2920 BH.

From what I read not all A/Cs run on DC power. How does one figure this out?

To be able to run the A/C during a hot summer I read one would need to have a 3000-4000 watt inverter, but that most trailers have a 1000-2000 watt inverter. I don't see anything on their site or in their brochure that gives specs on this either.

It seems there's some sort of inverter that works off of your propane? Maybe I've just had an overload of info reading from several sites.

I read lithium batteries are the better choice. Again a lack of info. Is this the typical battery on RV's? The Passport seems to be a bit more than a mediocre trailer.

30 amp service seems to be standard unless one has a 2 A/C trailer. I'm guessing there's no issues with upgrading to 50. This would mostly fix issues with running the A/C along with plenty of typical appliances, right?

I'm a bit fuzzy on the load divider. It ensures there's never an issue where the amp draw is too high?

It seems most trailers come with two batteries. This shows two banks of two. No desire to add any?

If 600 watts of solar panel can be set up well enough and the days are partly cloudy how long could this extend a boondock adventure in the summer running the A/C? What of a winter with the lows around 20* F? I'm guessing with neither the A/C or heat working this amount might keep everything else running indefinitely?

Do the trailer batteries do fine when constantly hooked to AC power? I know many batteries don't do well over time like that as batteries are meant to be well used and then charged. I ruined an iPhone keeping it charged.
  • Oh, and the RV has heat ducting to the tanks in a covered basement. R 11 in the floor and ceiling and 7 in the walls.
  • I was vague when I asked about an A/C system running on DC power. I meant with an inverter as I know these run strictly on 120 v AC. It was this inverter coming installed in an RV I was questioning as it stated they typically come with about half of that. Keystone doesn't mention this.

    I was wondering, if with the proper sized inverter, running an A/C could be done using a generator to recharge during the day. It seems a bank of 4 (unknown output batteries) aren't up to the task for long enough. And with quiet time at parks you couldn't run it at night.

    I don't think I'd want to install solar panels on the RV, though being 32' 10" I'd think there'd be plenty of room as the 315 watt panels I looked at briefly were 65 x 40" each. I'd prefer o park under shade and use a stand to support the panels. Each weigh 40 lbs which isn't too ridiculous individually.

    We would typically set up at a place with power and water but don't want to be confined to such. And it is for that that we'd like some solar and a generator. But I was curious how well just solar would do in helping extend the stay not knowing the A/C would drain the batteries that quickly. As such it might run for a few minutes?
  • rodwha wrote:
    I've been reading up on power needs and uses, but things aren't quite clear.

    For starters I'm looking at the Keystone Passport 2920 BH.

    From what I read not all A/Cs run on DC power. How does one figure this out? Lights will rin on 12VDC. AC will run on 120VAC

    To be able to run the A/C during a hot summer I read one would need to have a 3000-4000 watt inverter, but that most trailers have a 1000-2000 watt inverter. I don't see anything on their site or in their brochure that gives specs on this either.There is not enough batyeries to run an AC unit for more than a few minutes. Forget this notion

    It seems there's some sort of inverter that works off of your propane? Maybe I've just had an overload of info reading from several sites.

    I read lithium batteries are the better choice. Again a lack of info. Is this the typical battery on RV's? The Passport seems to be a bit more than a mediocre trailer.

    30 amp service seems to be standard unless one has a 2 A/C trailer. I'm guessing there's no issues with upgrading to 50. This would mostly fix issues with running the A/C along with plenty of typical appliances, right?Lots more involved than simply adding a 50 A cord set. Can be done, but usually cost prohivitive

    I'm a bit fuzzy on the load divider. It ensures there's never an issue where the amp draw is too high?

    It seems most trailers come with two batteries. This shows two banks of two. No desire to add any?

    If 600 watts of solar panel can be set up well enough and the days are partly cloudy how long could this extend a boondock adventure in the summer running the A/C? What of a winter with the lows around 20* F? I'm guessing with neither the A/C or heat working this amount might keep everything else running indefinitely?Thsts a lot of panels. I doubt you have sufficient roof space

    Do the trailer batteries do fine when constantly hooked to AC power? I know many batteries don't do well over time like that as batteries are meant to be well used and then charged. I ruined an iPhone keeping it charged.
    Modern converters do this fine keeping batteries up
  • rodwha wrote:


    From what I read not all A/Cs run on DC power. How does one figure this out?



    I've never heard of an rv AC running on anything but 120vac. You either have to have shore power, generator power, or inverter power.....all are 120vac.

    However, using an inverter will deplete your 12vdc battery power quite quickly and is never a good idea. Most rv solar panels are only good to keep your starting battery(s) charged and even if it is connected to your house battery(s), it could not keep up with the DC draw by the inverter
    when running one or more AC units.

    Ron
  • Most if not all ac's run on AC power , you would need a very large and expensive inverter and battery bank to run your air conditioner on a DC converted to AC power source. Most people that require the use of there AC without hookups either have one 3000 watt generator or a pair of 2000 watt generators with a parallel kit which is what we use . We also have a 100 watt solar panel that keeps the house batteries charged most of the time and LED bulbs have been installed to use less power when dry camping. is your trailer a 4 season trailer if not and even if it is your going to being using a lot of battery running your heating furnace blower motor (DC) if your out below 20 degrees. good luck with your adventure
  • For air conditioning you need 3000+ watt generator burning gasoline, diesel or propane.

    Solar? You would need 3000+ watts and a very large lithium battery and inverter. Easy $15/$20,000

    Most trailers come with a small 12v battery that may run 12v lights and furnace for 12 to 24 hours if you conserve. The rest is on you.

    Honestly if I need air 24/7 I am looking for hookups or sweat it out.
  • running some aCs on battery/solar will take a bunch of expense to do. AFAIK, all standard ACs run on 120 volt AC, not DC.
    you will need a 3000 and up generator.
    bumpy