Thread: 120V AC to 12vDC power converter for fridge?

  1. #1
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    Default 120V AC to 12vDC power converter for fridge?

    Unlike the more expensive models, my Dometic CF18 fridge does not have a 120vAC option. However, wife and I will be camping out, most likely at a developed campsite, next month and we will probably have 120Vac power. Can someone recommend a 120vAC to 12vDC power converter that can run the fridge? I guess I could look at an RV shop, they should have something, but I wanted to see if there were any specific recommendations.
    Martin AKA Zapp Branigan KD0PHH
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  2. #2
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    Actually, check out any places that salvage RV's and campers. Most have one and they are easy to find cheap. I paid about $30 for mine. It charges the batteries and also provides the voltage for the lights, etc.
    Tom Houston - Past NAXJA Colorado Chapter President - Past National NAXJA President
    Loveland, Colorado
    My Teardrop Build http://www.expeditionportal.com/foru...ardrop-trailer

  3. #3
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    Most of the better "battery chargers" are also "power supplies". Iota and Samlex both say in their brochures that they can be used as power supplies.

    My little Norcold 323 says on the sticker that it uses 11.7a running on 12v - so I'd say any decent MULTI-stage (so it eventually goes to float and doesn't overcharge the battery) charger hooked up to shore power should not only supply enough power, but also might just keep your battery topped up at the same time - as long as it is rated to supply at least however much your fridge draws.
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  4. #4
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    Quote Originally Posted by dwh View Post
    Most of the better "battery chargers" are also "power supplies". Iota and Samlex both say in their brochures that they can be used as power supplies.

    My little Norcold 323 says on the sticker that it uses 11.7a running on 12v - so I'd say any decent MULTI-stage (so it eventually goes to float and doesn't overcharge the battery) charger hooked up to shore power should not only supply enough power, but also might just keep your battery topped up at the same time - as long as it is rated to supply at least however much your fridge draws.
    Sorry, I guess I should have made it clear: The 4runner may not be around when the fridge is plugged in.

    We have a teardrop trailer, and what I'm thinking is that we will get to the campsite, set up the trailer, and put the fridge in the teardrop while we go into town, go fishing, etc. That way our stuff stays cold (running on 120vAC power at the campsite) while we're gone. Our teardrop has a shore power connection with standard 120vAC so what I would need is something I can plug into that 120vAC power strip that has a socket I can plug the 12vDC fridge into.
    Martin AKA Zapp Branigan KD0PHH
    2007 Toyota 4runner SR5, 4.0 V6

    Wife's Vehicle: 1995 YJ "Captain Morgan"

    And our Homebuilt Teardrop Trailer "Bubbles!"Other Rides: 2008 Triumph Scrambler; 1997 Mazda Protege (Daily Driver)

    "I am the Man with No Name - Zapp Branigan!"

  5. #5
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    This is what they are talking about
    http://www.iotaengineering.com/dls30.htm
    dlm30_10.jpg

    30 amps of clean 12v supply, afuse and matching socket and your done

  6. #6
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    here's a bargain

    15amp 12V
    for only 18usd !

    http://www.amazon.com/Switching-Powe...p+power+supply

  7. #7
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    You're using this to do nothing more than power the fridge from 120VAC? (there's no battery in your trailer)?

    If so, I would say find a simple 120VAC to 12 VDC power supply (like what you'd test a car stereo with or to run a mobile ham radio with in your home) and just run it off that. Get one that's sized at least 50-75% above what current your fridge pulls while it's running (say the fridge pulls 4 amps, get a 6-8 or so amp unit. This so it hopefully won't hit max temps running on a hot day).


    Looks like a unit actually made for your application:
    http://www.amazon.com/Schumacher-PC-.../ref=pd_cp_e_3

    This would work too, but may be overkill (unless you have other stuff you want to run off it):
    http://www.amazon.com/Pyramid-13-8-V...ef=pd_sim_hi_1
    1990 Ford Bronco II, dual t-case, locked up on 35s

  8. #8
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    I'd suggest finding a way to install a battery, such as an AGM and a power supply/charger to "match". This way the battery acts as a sponge to minimize voltage fluctuations. Unless I've had a fully regulated power supply, the unloaded voltage goes way up. This caused me some issues with electronic stuff, until I got smart and got a battery.

    An AGM battery will give off essentially no fumes. I have an Odyssey PC2250 in a cargo trailer, under the bunk, with an IOTA charger attached as DWH recommended. NO fumes and it is just there for use as needed. I do connect to the tow vehicle for charging when traveling along the road, the IOTA when connected to shore power.

    HTH

  9. #9
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    You might be able to get away with an old pc power supply. Can't recall how many amps they put out...
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  10. #10
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    Quote Originally Posted by Douglas S. View Post
    You might be able to get away with an old pc power supply. Can't recall how many amps they put out...
    This is exactly how I power my dometec/waeco model that lacks the on board power supply. They are not all rated the same. The old power supply I found is rated at 12A. I added a large capacitor on the output for powering the fridge so the voltage does not dip to cut out level when it powers on. I also use it to supply 12V DC to a universal smart battery charger.

    Here is a great link for learning how to mod the computer power supply.

    http://jumperone.com/2011/06/atx-power-supply-tutorial/

    Since I use my power supply to run the fridge as a beer cooler in the house I also added a usb outlet for charging various things. The 5v side is rated at 20A so it could charge a lot of usb devices.
    http://servicedriven.org

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