Forum Discussion

Trackrig's avatar
Trackrig
Explorer II
May 18, 2016

Making sure how to test new RV outlets.

I'm having 400A service and RV outlets installed on a piece of property we bought in Washington. There will be three outlet boxes installed like you find at most RV parks with 1ea 50A, 1ea 30A 2ea 20A outlets and their respective breakers. When the outlets are installed I'll test them before plugging in. I want to be sure this is what I should find.

When I test it with voltmeter, this is what I believe I should find - look down about 5" from the top of the page - for some reason I couldn't cut and paste just the testing / readings part. There are examples for both 50A and 30A. Go to the upper left corner to the Electrical Testing tab.

RV outlet readings.

If something is wrong that my testing misses somehow, I have a hardwired 50A Surge Guard that should protect me. It is interesting that so far in being out for 6 months a year for three years I haven't run across any bad power in an RV park that the Surge Guard hasn't liked. We've been in a lot of places as we never stay anyplace long than 3 - 4 days.

Thanks,

Bill
  • RoyB's avatar
    RoyB
    Explorer II
    May 18, 2016
    50A SERVICE from NOSHOCKZONE


    30A-20A SERVICE from NOSHOCKZONE


    This is how a typical PEDESTAL is wired for RV Service...

    From GOOGLE SEARCH...

    I may have sent this to you before...
    Roy Ken
  • rockhillmanor's avatar
    rockhillmanor
    Explorer
    May 18, 2016
    Can't offer you advice on testing BUT:
    It is real good to hear you are going to TEST them before using them.

    I sound like a broken record but I too 'hired and electrician' to put my shore station pedestal in on my property. I explicitly showed him what 30 amp RV outlet to use and that it was not 220.

    I came home from a trip late at night after it was installed and just plugged in. Boom. $3,000 in damage to the MH. He wired it wrong.

    So kudos for taking the initiative to test first even if you hire an 'electrician', and hopefully other forum members reading this will do the same and avoid a costly mistake.
  • Trackrig's avatar
    Trackrig
    Explorer II
    May 18, 2016
    Dusty R wrote:
    Why a 400 amp service? That is a LOT of power.


    Yes, it is a lot, but when I remodeled the current house we put in 200A and I find myself running short for some things I'd like to do.

    On this piece of property it is especially a lot of some MHs, but there will be a large shop built first that two MHs can be stored in, plus work areas and then a house. During the summer months I would expect to have one or two friends visiting in their MHs and it's often around 90F so there will be a bit of A/C running. (And they don't charge any more to put 400A service in.)

    Bill
  • rockhillmanor's avatar
    rockhillmanor
    Explorer
    May 18, 2016
    RoyB wrote:
    50A SERVICE from NOSHOCKZONE


    30A-20A SERVICE from NOSHOCKZONE


    This is how a typical PEDESTAL is wired for RV Service...

    From GOOGLE SEARCH...

    I may have sent this to you before...
    Roy Ken

    Thanks for posting this
    This is by far the GREATEST diagram. Far better than the myrv.us/electric/

    This should be a 'sticky' marked important electrical info. If it is not already one.
  • DrewE's avatar
    DrewE
    Explorer II
    May 18, 2016
    As you're (presumably) using prewired pedestal boxes that just need the main feed wires connected and they're good to go, I would not generally expect any electrician to have difficulty. That's not to suggest that checking things is at all a bad idea, if only because everybody can make a mistake or two from time to time.

    The main difficulty with wiring RV outlets is with the 30A receptacles. 50A RV receptacles are identical to current 4 wire electric range outlets that any electrician should be familiar with. The 30A RV outlets, though, are superficially similar in appearance to old 30A 240V 3 wire clothes dryer outlets, but unlike them must not be wired for 240V service.
  • time2roll's avatar
    time2roll
    Nomad
    May 18, 2016
    Trackrig wrote:
    If something is wrong that my testing misses somehow, I have a hardwired 50A Surge Guard that should protect me. It is interesting that so far in being out for 6 months a year for three years I haven't run across any bad power in an RV park that the Surge Guard hasn't liked. We've been in a lot of places as we never stay anyplace long than 3 - 4 days.

    Thanks,

    Bill
    Must stay in fancy places. My EMS finds something every year at least. High voltage, low voltage, bad ground seem most common. Have yet to see reverse polarity. All this trouble is probably less likely on 50 amp service.
  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    May 18, 2016
    Industrial transformers are used on 400 ampere 240 3-wire service drops. Usually they have cooling fins on their exterior. The Kernuy nut clamps used on the distribution lines are twice as thick and are double clamped and many utilities seal 400 A service drops with weatherproof sealant. Once a year flood the grounding rod area with water if you live in a dry climate.

    Phase to phase (240) must be rational as would be each phase to neutral. No more than 5-volts difference. When you go to install your main 400-amp panel make it so load (breaker) wires can be switched phase to phase if necessary to keep the load balanced.

    Potential between phase to earth ground must be exactly the same at outlets as it is at the place where the earth grounding rod from the service drop is positioned. Potential at any point between neutral and earth ground is not to be permitted.
  • BB_TX's avatar
    BB_TX
    Nomad
    May 18, 2016
    Trackrig wrote:
    ...............

    RV outlet readings.

    Thanks,

    Bill

    I made one of the 50 amp testers as shown in the link you posted. The first thing I do after pulling into a new site is plug the tester in the pedastal to make sure wiring and voltage are correct. Quick and easy. If I happen to be in a 30 amp site I just use my 50/30 adapter and use the same tester.

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