I need help w/ 6V batteries and converter and inverter

Discussion in 'The Projects Forum' started by wconant, Jun 28, 2012.

  1. wconant

    Thread Starter New Member

    Jun 27, 2012
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    Hello,
    I'm new to all this and trying to figure out how to hook up a battery system for my camper trailer.
    This is what I'm looking at.....

    Generator to AC Breaker box. Box breaks to the outlets and appliances one way and then to a converter/charger another way. From the converter it goes to the battery bank (which would be 2 6V batteries) from the battery bank to an inverter and then back to the AC Breaker Box.

    I think that is a good system. But my questions are........

    1. Since I'm using 6V batteries does my inverter have to be 6V or because the 2 6V make 12V it should be a 12V inverter?

    2. Similar - the converter - should it be 6V or 12V because of the batteries. I'm confused because they will be 6V but be putting out 12V.

    3. Plus I'm not even sure how to wire everything at the AC Breaker box.

    Please advise.
    Thanks
    William
     
  2. bountyhunter

    Well-Known Member

    Sep 7, 2009
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    You can stack two similar 6V batteries in series for auto usage. That's how cars did it back in the 50's when they transitioned from 6V systems to 12V.
     
  3. wayneh

    Expert

    Sep 9, 2010
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    Then please move slowly with extreme caution and post plenty of questions and pictures here, to get help. Mistakes on such things can be costly at best and fatal at worst. And mistakes are stunningly easy to make, even for the most experienced. That's just the way nature works.

    You've described your goal but it's not clear (to me, anyway). Consider posting a block diagram with as many details as possible regarding the individual components you are using; voltage, current, frequency specs, whatever you can find. Take and post pictures of anything that's faster to show than to describe - and that's almost everything. Remember, we can't read your mind.
     
  4. Brownout

    Well-Known Member

    Jan 10, 2012
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    Not a good idea to wire the inverter back to the breaker box. You need a "switchover" device to switch between the generator and inverter. Never wire the two together!


    Why are you using 6V batteries? The conventional way to do this is to use a 12V deep cycle battery. It has to be deep cycle, or else you'll destroy the batter eventually.
     
  5. wconant

    Thread Starter New Member

    Jun 27, 2012
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    Thank you with your help.
    I am posting a picture of what I am trying to do.

    As far as 6V batteries, I was told that they last longer than 12V batteries, even if they are deep cycle. Maybe someone else could advise?

    Thanks for your help
    William
     
  6. wconant

    Thread Starter New Member

    Jun 27, 2012
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    Anyone have a recommendation for an inverter that is modified sine with a charger all in one. Just looking for a good brand that is dependable and not gonna break the bank.
    Thanks
    William
     
  7. strantor

    AAC Fanatic!

    Oct 3, 2010
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    I assume your 2 6v batteries are in series so they output 12V together. in this case your inverter and charger should both be 12V.

    What is your amp requirement for the 120VAC? If You don't have this figure, we can figure it out. Just post the rated power from the nameplate of each device you intend to power simultaneously.
     
  8. wconant

    Thread Starter New Member

    Jun 27, 2012
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    Thanks Strantor,

    So I tried to go online and makes these all the same but I got too confused and didn't want to mess up. So here is the list....

    Fridge - 1/8 H.P 115V 60 CVC A.C - that would run 24hrs
    2 Lights - 60 Watts - probably run 2 hours a day
    Blowdryer - 900-1500 watts (from internet) less than an hour a day
    ipod player - 60 watts - 12 hours a day
    ipod charger - 5V 1.0A - 12 hours a day

    That is probably all we would use. I put the amount of time in hopes that someone could help me figure out AMP Hours. and also then I could know what size watt inverter I would need.

    Thanks for your help.
    William
     
  9. strantor

    AAC Fanatic!

    Oct 3, 2010
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    you're not going to flick on a 10 million candlepower spotlight at any point?
     
  10. strantor

    AAC Fanatic!

    Oct 3, 2010
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    I'm thinking 2KW is the minimum. When I add it all up it's around 1800W but i round up to be safe. never know, maybe the kids want to bring the laptop in the future or something.

    So This camper thing is sort of a grey area as I see it. It's not residential, commercial, or automotive. I don't know if (i doubt) any code applies to it. If I were in your situation I would probably not use the grid tie transfer switch that (I think) brownout is talking about; I would use a pair of interlocked 20A contactors to switch between inverter and generator. Or, get a 2kw UPS that is your "an inverter that is modified sine with a charger all in one" plus batteries.
     
  11. strantor

    AAC Fanatic!

    Oct 3, 2010
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    A bit of reading has uncovered what Brownout was more likely referring to. these. I actually would recommend these over the contactors; they are about the same price.
     
  12. wconant

    Thread Starter New Member

    Jun 27, 2012
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    Strantor,
    Thanks so much for your help.

    I am really confused about the contactors. I don't know what they are or where they would go.
    Any chance you could give me a diagram?

    Also, this guy has a switch and fuses. Do I need something like this?
    http://www.macandchris.com/12vdcElectricSystem.htm#Inverter

    Also, I was thinking of getting rid of the converter and just using a inverter with a charger in it. Not sure if I already made that point.
    Do you recommend that?

    Thanks
    William
     
  13. strantor

    AAC Fanatic!

    Oct 3, 2010
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    It's either the contactors or the transfer switch. Since the I found the transfer switches to be just as or more affordable as the contactors, I recommend the transfer switch instead.

    Yes you should have a main disconnect switch. I apologize but I frequently forget to specify that yes, fuses should be used; I get so used to fuses that I consider them a given. The load you've specified is around 16A max; what guage wires are you using?

    The inverter/charger setup sounds ideal since you already have batteries. It's basically an UPS without the batteries. However I couldn't find one >750W. You need 2000W. if you can find a 2000W inverter/charger than that would be good. The only thing I could find in that range were UPSs and they are around 700-1500$.
     
  14. wconant

    Thread Starter New Member

    Jun 27, 2012
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    0
    Thanks

    Here is a inverter/charger I was looking at. Its a little pricey but it looks like a really good one. Tell me what you think. If you know of one that is almost as good but cheaper, please share. haha
    http://www.donrowe.com/inverters/me_series.html

    Any chance you could draw me up a diagram with where the fuses would go and the main disconnect switch?

    Here is what I think it should look like, without fuses and disconnect switch.
     
  15. wconant

    Thread Starter New Member

    Jun 27, 2012
    19
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    I messed up on my picture.

    It should go from Battery bank to Inverter, then to the plug.

    New picture.
     
  16. Brownout

    Well-Known Member

    Jan 10, 2012
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    Be advised that you will not be able to run all your appliances in a modified sine wave inverter. I use one for camping, and I can run some, not all appliances. You'll need to test each appliance you're planning to run. Some things, like refrigerators I would not even try.
     
  17. wconant

    Thread Starter New Member

    Jun 27, 2012
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    Brownout - Thanks for the advise, I'll get the pure sine wave then.

    Can anyone please take my diagram and recreate it with the proper placement for the fuse(s) and the shut off switch. I really need some
    help with this.

    Thanks
     
  18. wayneh

    Expert

    Sep 9, 2010
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    You may change your mind when you price the pure sine inverter. :D You could buy a LOT of ice for the cooler.
     
  19. wconant

    Thread Starter New Member

    Jun 27, 2012
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    Wayneh,
    Ya, I've been trying to swallow that pill for a few days now.
    Do you know of any good inverter/chargers that are pure sine wave that won't break the bank?
    Or would getting a pure sine wave inverter and then a separate charger be a better and cheaper way?

    Thanks
     
    Last edited: Jul 2, 2012
  20. wayneh

    Expert

    Sep 9, 2010
    12,153
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    I don't.

    I stayed on a floating cabin once in British Columbia, way off grid. It had a utility room with a bunch of batteries which we had to recharge by running a generator every once in a while. All the power for the cabin, including small but normal kitchen appliances, was provided by the batteries.

    My point is, what you want is probably out there and if you look around in the right circles, you might find more options.
     
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