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cac43's avatar
cac43
Explorer
Apr 04, 2021

how long of a 12 ga extension cord is safe to use

our daughter she would help us when we go visit her with our class C. she installed a singles 30 amp rv plug in at the side other house for us to use. problem is the outlets almost 100 feet
away from where we park. because of power loss from distance, I'm afraid that it will not work from that distance even if we only have fridge and ac running- would turn off ac if need to use microwave. any advice ? thanks. chuck

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  • JRscooby's avatar
    JRscooby
    Explorer II
    Apr 04, 2021
    When thinking about voltage drop you need to also think about how long is the run from breaker to outlet.
    My AC has a 20 AMP plug on the cord. When I want to run AC when not plugged into a 30 Amp, I don't plug in the trailer, I plug in the AC
  • pianotuna's avatar
    pianotuna
    Nomad III
    Apr 04, 2021
    Hi,

    You have correctly identified voltage drop as a problem. #10 wire may not be enough to solve this issue.

    On 30 amps, it is not advised to run the air conditioner and microwave at the same time.

    The best solution may be an autoformer. See my signature for the one I use. If you have a friend who travels to Mexico--they are an off the shelf item.
  • RichB3125's avatar
    RichB3125
    Explorer
    Apr 04, 2021
    Buy three 30A extension cords plus the one on the rv. Then you should not have any problems unless you really overload the system.

    Rich
  • Ed_Gee's avatar
    Ed_Gee
    Explorer II
    Apr 04, 2021
    Without AIr Condx I have often used 2 50' 12Ga extension cords with no problems on my 30A RV. If possible, you might try using 1 50' 12 gage cord to your RV's shore power cord ... which is 10 gage.... if it will reach.

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