There is a large amount of information on this subject, but most of it assumes a level of knowledge that I do not yet possess! I just bought a small toyota class C motorhome and I have a very limited amount of time to sort out the electrical so was hoping someone could help me out. My goal is to be able to go 3 days without plugging in, and run a swamp cooler all day plus tv and laptop a few hours a day. I bought 2 6v deep cell batteries. From what I can tell, I need a battery monitor, a generator, an inverter, and a battery charger - is this correct? What is a shunt for the battery monitor? And I'm sure this is a stupid question, but do I have to unplug the batteries to charge them? My batteries will be vented to the outside, but they are located in the RV and not easily removed except through the inside of the RV.
Any insight would be very much appreciated! Thanks!
Welcome,
There is no way in heck you are going to be able to run a swamp cooler from battery power alone. Remember for every 1 amp of 120VAC power you will remove approx 10 amps of 12VDC power from your batteries. Your 6 volt batteries will have around 150 amps total for you to work with. Running a small electric motor could kill your batteries in less than 6 hours. You need to educate yourself about power and power management. Search the web for "12 side of life" as a start
Watching TV for a couple of hours a day is not too bad. But you still need to figure out how to recharge the batteries during the day or you could be DOA be the end of the second day.
For the rest of it, no you do not have to unplug the batteries to recharge them. You simply plug the generator into the shore power cord from the MH.
As for battery monitor, you can buy from EBAY sellers inexpensive XX.XX digital gages that will read battery voltage. The same sellers also sell battery amp meters complete and ready to install.
Donn,Lorri,Max (The Rescued Lab)
Resident Know It All
I've never used a battery moniter so I can't help you there.
If you have a generator, I would run it when you need to use the swamp cooler. Chances are you will charge the batteries as well provided your generator has capacity beyond the draw of the swamp cooler.
The inverter will supply power for the laptop and TV you should be able to go for 6-10 hours with two batteries, using just the TV & laptop.
I used a 1000 watt generator to charge my 2 batteries during the day and then we would watch TV and use the laptop off of the inverter from 5PM to midnight.
ok, that's definitely helpful! The swamp cooler (TurboKool) is supposed to draw less than 5 amps @ 12 v, which I interpreted as easily being able run all day off battery power....
Solar panels would help keep the batteries up. And you ought to visit these guys: http://www.toyotamotorhomes.com/
Welcome aboard. My first motorhome was a 1987 Sunrader on a Toyota chassis.
And really your post should have been in the Class C forum
After researching boondocking and power needs all over the internet and finding bits and pieces of information, the two best overview sources I came across are this PDF
and the book "The Complete Book of Boondock RVing" by Bill and Jan Moeller.
This book is well worth the $16.95 cost and it is available from amazon.com. It covers all aspects of boondocking and half of the book covers developing a power budget, conserving usage, and power generation with gensets and solar. Lots of good information that is very well organized and easy to read and understand by anyone.
The Jack Danmayer site is quite nice. It is slightly dated and there are some new controllers out there to be considered such as the Rogue 3024.
Start with an energy audit. For a battery only system take the total 24 hour use and multiply by 7. This will allow three days on battery and also allows for aging and a "cushion".
If space is a concern then a small 1000 watt inverter generator will probably be on your "list" of items to consider.
I prefer solar myself and could, with my system, run a swamp cooler and laptop 24/7 literally forever.
I always camp in the woods. Have never been in a rv park. I use walmarts everstart maxx grp 29 marine/deep cycle (2). I run the gen about an hr in the morning doing coffee & breakfast. 300w invertor for movies @ night. Never run out of power and Batt are 7 yrs old. A lot of it is the elec system and convertor in the rv. Some trailers I have owned were not this good.
Glen
04 Tail gator XT 34' 5th wheel garage model
99 F350 CC DRW 7.3 ais intake, adrenaline hpop, JW valve body,
cooling mist water inj, DP tunes, 4" turbo back exh sys
trucool trans cooler added
08 Arctic Cat Prowler 700XTX
Let's say the swamp cooler draws 4 amps and is used for ten hours per day. 4 x 10 = 40 amp-hours. Typically an rv may draw 30 amp-hours a day for "parasitic" loads. Let's add 10 more amp-hours for other uses. The total demand so far, is 80 amp-hours per day.
Battery capacity for an 80 amp-hour draw needs to be at least 160 amp-hours. Three day's worth suggests a battery bank of 480 amp-hours. It may not be possible to add that much capacity and weight to a smallish motor home.
There has to be some way to replace that 80 amp-hours. I chose to do it with solar. Another way is to beef up the OEM charging circuit from the alternator to the house battery bank. A third way is to have a good 3 stage "converter" in the RV and use a small generator.
Amelda3 wrote: ok, that's definitely helpful! The swamp cooler (TurboKool) is supposed to draw less than 5 amps @ 12 v, which I interpreted as easily being able run all day off battery power....
Amelda3 wrote: ok, that's definitely helpful! The swamp cooler (TurboKool) is supposed to draw less than 5 amps @ 12 v, which I interpreted as easily being able run all day off battery power....
It it is true that the cooler will only draw 5A, then you probably could do this, particularly when you plan to run a generator at least several hours in the evenings for TV and such. But there is another serious problem with this plan if you are expecting to park somewhere with no utilities and that is a supply of water for an evaporative cooler. They use large amounts of water and if that water is hing in mineral content it will also very quickly built up deposits on everything.
Good travelin! ........Kirk
Professional Volunteer
Fulltimer for 11 years, URL:www.adventure.1tree.net