Rv Electrical Plug Configuration

Discussion in 'General Community Discussions' started by FosterImposters, Sep 9, 2009.

  1. FosterImposters

    FosterImposters
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    Preparing to join family this fall in the Midwest, and have a question: thought I'd discover if any of you all may help.

    I'm thinking that some of you (?) have their 50amp rigs housed beside your home/garage when not in use, and have already addressed the question with plugging your 50amp RV into the 220volt home/garage receptacles.

    In year's past, we traveled in a 30amp Class C RV and could just plug-in at arrival at a correctly fused 110 volt outlet at the family's home/workshop at their ranch. Used one of their workshop outlets as this was traditionally used (and fused) for running all kinds of compressers, generators and tool-stuff. (They run a heavy equipment repair business).

    Now we travel in a 50amp Class A RV. All the 220 volt equipment and plugs (at their workshop) have what they call a 'crowsfoot' configuration...3 slots.

    Do I just need to purchase a 'configuration adaptor' to fit our RV 50amp cord plug (one prong, one L-shaped and two flats), into their 3 slot 220volt receptacles?

    I wish to arrive with the correct plugs/cords/adaptors... :rolleyes:
    Thanks for your insights folks.
     
  2. Denali

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    QUOTE(FosterImposters @ Sep 9 2009, 03:31 PM) [snapback]18825[/snapback]
    Now we travel in a 50amp Class A RV. All the 220 volt equipment and plugs (at their workshop) have what they call a 'crowsfoot' configuration...3 slots.

    Do I just need to purchase a 'configuration adaptor' to fit our RV 50amp cord plug (one prong, one L-shaped and two flats), into their 3 slot 220volt receptacles?

    I wish to arrive with the correct plugs/cords/adaptors... :rolleyes:
    Thanks for your insights folks.

    If by 'configuration adaptor' you mean an RV "dog-bone adapter" that is used to allow you to plug your four-prong 50-amp RV into a three-prong 30 amp RV plug, then no. That would put 220 volts on your 110 volt equipment, allowing the blue smoke to escape.

    An RV 50 amp system keeps the neutral and ground separated inside the RV. Older 220 volt systems in buildings, with those three-prong connectors, bond neutral and ground. If you jury-rigged an adapter to use one of those receptacles, you would have a dangerous situation.

    Newer 220 volt wiring uses four-prong connectors similar to your RV, although the connectors are shaped differently.

    The only good solution is to install a dedicated 50 amp RV plug. That's what we did.

    (BTW, for some reason what we previously called 110/220 volt systems are now 120/240 volts.)

    --
    Dave Rudisill
    Coos Bay, OR
     
  3. RV Camper1

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    The three pin plug that you have does not have the required four leads which your RV needs. What you need is a four pin, 120/240V plug and it should be supplied by a properly protected circuit breaker. Most dryer outlets in new homes are of this configuration.

    Your RV plug is a standard 120/240V plug. To wire one you need to have from the power distribution panel, a ground, a neutral, and both L1 & L2 hot leads, which means both phases of power. What you have not does not have the ground lead to it and there is no safe way to get around that shortfall.

    By the way, I am a retired electrical service tech and worked in the field for 40 years. There are ways to connect to what you have, but if you make a mistake you will damage the equipment in the RV and if something goes wrong you my set it on fire or electrocute someone.
     
  4. Denali

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    QUOTE(Kirk @ Sep 13 2009, 08:41 PM) [snapback]18904[/snapback]

    The three pin plug that you have does not have the required four leads which your RV needs. What you need is a four pin, 120/240V plug and it should be supplied by a properly protected circuit breaker. Most dryer outlets in new homes are of this configuration.

    Your RV plug is a standard 120/240V plug. To wire one you need to have from the power distribution panel, a ground, a neutral, and both L1 & L2 hot leads, which means both phases of power. What you have not does not have the ground lead to it and there is no safe way to get around that shortfall.

    By the way, I am a retired electrical service tech and worked in the field for 40 years. There are ways to connect to what you have, but if you make a mistake you will damage the equipment in the RV and if something goes wrong you my set it on fire or electrocute someone.

    Kirk:

    When you say that "Your RV plug is a standard 120/240V plug" and "Most dryer outlets in new homes are of this configuration", someone could misinterpret this to mean that an RV plug is the same as a dryer plug.

    As you know, the neutral prong on a dryer plug is L-shaped, unlike an RV plug. An RV plug is the same as a stove plug, though, isn't it?

    --
    Dave, no electrician
     
  5. RLM

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    There was an article on this very subject in a recent FMCA magazine. Even if you aren't a member you may be able to browse the website and find it. http://www.fmca.com/

    I absolutely agree with Kirk. Despite having some experience, I hired a master electrician to do the connection on my RV pad. Piece of mind is priceless.
     
  6. FosterImposters

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    Sure appreciate everyone's replies here. I've learned this is NOT as simple as just using some kind of converter plug...(yikes). :p

    Thanks so much for everyone's patience with my naive electrical questions. Good grief: the more I read the more I can understand how we can get ourselves into a very dangerous pickle with very little effort.
    And yes: there WILL be an electrician pressed into service when we arrive in the boondocks of southwest Iowa. (Piece of mind is indeed, priceless!)

    Cheers!
     
  7. RV Camper1

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    Dave, no electrician

    You are correct, but no RVer will plug into it because the RV plug will not fit and there is no adapter to make it so. The difference in the two plugs is due to the current rating and not the voltage. Codes do not allow the use of a plug that will fit into the lower rated outlet with heavy equipment. I am not quite sure where the adapters that we find so common for RVs between the 30A & the 50A cords fit into the codes, but the rules for homes and businesses are very specific and pretty narrow.

    Were it not for the pin shape, it would harm nothing at all for a 50A RV to be plugged into the modern 4 pin dryer outlet, but it would be limited to 30A per leg, rather than the 50A per leg that we are used to. I do know how they are wired as I just finished putting one in today.

    And while I am not a licensed electrician, I have worked in electrical work for more than 45 years and am familiar with most electrical codes for homes and RV, but not industrial.
     
  8. John316

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    QUOTE(Kirk @ Sep 16 2009, 10:30 PM) [snapback]18972[/snapback]


    And while I am not a licensed electrician, I have worked in electrical work for more than 456 years and am familiar with most electrical codes for homes and RV, but not industrial.



    Kirk,

    You are quite the guy. I wouldn't mind if you pass on, just 75 years of your experience to me :D Just kidding.

    With our setup, I had to wire a new plug in for switching from shore power, to generator (we don't have a switch yet). When we made ours, we just used a standard HD receptacle. Works for me.

    BTW, I haven't experimented, however, often one can switch the prongs out. Might be able to make an adapter that way.

    God bless,

    John
     
  9. Texasrvers

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    QUOTE(Kirk @ Sep 16 2009, 10:30 PM) [snapback]18972[/snapback]

    I have worked in electrical work for more than 456 years



    My goodness, are you like the world's first electrician?? :huh: :lol:
     
  10. RV Camper1

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    There was a bit of a typo there! I edited it to be more accurate as I may be over the hill, but I didn't invent electricity!
     

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