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allen8106's avatar
allen8106
Explorer
Oct 23, 2014

12 Volt Power to My Outlets

So I am wanting to start boondocking some. I plan to start out slow with short excursions, 2-3 days. My problem is that my wife uses a cpap at night. It runs on 12 volts because the output of the power transformer that came with it says the output is 12 volts. My problem is that based on a review of my rig wiring schematics none of my electrical outlet are in the 12 volt circuit. Two questions:

1) Is it normal not to have any of the outlets in the 12 volt circuit?

2) Assuming the above is true any recommendations for getting 12 volt power in a few outlets? Either the original outlets or a couple new ones I would install.

I assume it's not a good idea rewire the original outlet into the 12 volt circuit.

27 Replies

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  • steveh27's avatar
    steveh27
    Explorer
    Oct 23, 2014
    Inverters draw power on their own. Not good for boondocking. MY tv was the same with a power cord which had the 12 volt converter built in. I made a 12 v power cord from Radio Shack & plug into 12 v now & draw much less power than through an inverter.
  • beemerphile1's avatar
    beemerphile1
    Explorer
    Oct 23, 2014
    allen8106 wrote:

    1) Is it normal not to have any of the outlets in the 12 volt circuit?


    Typically there is one 12v receptacle at the location for the television.

    allen8106 wrote:

    2) Assuming the above is true any recommendations for getting 12 volt power in a few outlets?


    Go to your local auto parts store and buy 12v receptacles and install where you want them. I have installed several in every RV I have owned.

    robsouth wrote:
    bob213 wrote:
    Does your cpap transformer plug into 120v and then reduce down to a 12v output? If so, an inverter hooked to your battery array will give you 120v that you can plug the transformer in to. You can plug directly into the inverter or run a line to a new surface mount 120v receptacle dedicated to the cpap.


    Correct answer!


    No, wrong answer. It makes no sense to convert from 12vdc to 120vac and then back to 12vdc when you can just plug directly into 12vdc. My wife's CPAP operates directly from 12vdc with the appropriate cord and receptacle.
  • PaulJ2's avatar
    PaulJ2
    Explorer
    Oct 23, 2014
    I have a cpap with a 120v to 12v transformer output. However it's 12v output cord unplugs from the unit. You then use a 12v cord to plug into a standard round 12v outlet. It is a Philips Co unit.
    If not like that then an inverter is the way to go.
  • robsouth's avatar
    robsouth
    Explorer II
    Oct 23, 2014
    bob213 wrote:
    Does your cpap transformer plug into 120v and then reduce down to a 12v output? If so, an inverter hooked to your battery array will give you 120v that you can plug the transformer in to. You can plug directly into the inverter or run a line to a new surface mount 120v receptacle dedicated to the cpap.


    Correct answer!
  • bob213's avatar
    bob213
    Explorer
    Oct 23, 2014
    Does your cpap transformer plug into 120v and then reduce down to a 12v output? If so, an inverter hooked to your battery array will give you 120v that you can plug the transformer in to. You can plug directly into the inverter or run a line to a new surface mount 120v receptacle dedicated to the cpap.
  • pianotuna's avatar
    pianotuna
    Nomad III
    Oct 23, 2014
    Hi,

    You would need to run a line from the 12 volt distribution box with an appropriate size fuse. Use fairly thick wire (#8) to prevent voltage drop.

    Standard outlets (similar to your house) are never 12 volt DC. They are 120 volts A.C.
  • rvten's avatar
    rvten
    Explorer
    Oct 23, 2014
    1. Is yes.
    Install a 12 volt power outlet. Like you have on your dash.

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