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NEMA 14-50 outdoors

Discussion in 'North America' started by Effects, Aug 8, 2013.

  1. Effects

    Effects Member

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    What precautions and special installation practices for the NEMA 14-50 should be considered for charging in the rain? Thinking of safety for the operator.
     
  2. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    NEMA 3r (outdoor) rated enclosure for the receptacle is the big one, closed when not in use and preferrably one of the ones that opens upward rather than to the side (to provide shelter against rain from above.. Because of the size of the UMC's plug with an adapter attached, the typical RV box won't close on the cord, which would be better. Something like this: Eaton 50 Amp 1-Space 1-Circuit Temporary RV Power Outlet Box-CHU1S at The Home Depot

    The UMC is designed for weather-resistant use, so you're fine there, and the "coupling means" (the Tesla end of the connector) is relatively safe because the power is not applied to the longer portion of the cable until the car is attached and signaling with the UMC.

    The Tesla UMC contains ground fault protection circuitry, so the only thing you have to be concerned with is holding the plug correctly when you plug it in - don't have your hands near the prongs, grip the plug by the back of the barrel.
     
  3. wycolo

    wycolo Active Member

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    #3 wycolo, Aug 9, 2013
    Last edited: Aug 9, 2013
    At a campground the 14-50 box is right next to the meter and the breaker switch. Proper procedure is to be sure breaker is OFF, then hook up your charge cable, then finally flip breaker to ON. You could also wear a rubber high voltage glove on the one hand. And high voltage rubber boots like Tesla techs wear while digging into your MS. Your call.

    I can't remember if the breaker was part of the meter box and the 14-50 was separate, or if they were all part of the same unit. It was specially made for campgrounds, nice & compact.

    My 14-50 box (made by Eaton, bought at HD - same as link below) has room for a good sized breaker or switch to be installed in the box, but there is no knock-out for such. If the distribution panel is far away from the 14-50 location then it would be convenient to mount a DPST 50 Amp switch in the box (50 Amp minimum). If it won't fit then in its own box.

    From 14-50 box: "Turn disconnecting means or circuit breaker OFF before inserting or removing plug. Plug must be fully inserted or removed." So this seems to ok use of switch in series with the remote breaker. Flasher, please chime in!
    --
     
  4. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    #4 FlasherZ, Aug 9, 2013
    Last edited: Aug 9, 2013
    Code doesn't call for anything in particular - NEC 625 calls for an EVSE disconnect to be "accessible", but the 14-50 counts as a disconnect, and the code requiring GFCI's is limited to 125V/15-20A receptacles.

    It really depends on how safe you feel. You can always get a box with an integrated breaker, a la New Midwest Rainproof Power Outlet Box U054C w 50 Amp RV Receptacle Breaker | eBay (if unavailable, just search for "RV outlet box with breaker" in Google and you'll see a bunch). I would not try to engineer something in the Eaton box above, as you start to run near box fill issues and you'd violate listing on the device by modifying it.

    An even safer alternative would be to use that receptacle box I posted above with a GFCI breaker in your panel, such that it trips if there is any current that gets sunk to ground. You may end up with occasional nuisance tripping, though in rare cases -- and older RV's that bond neutral to ground will cause trips as well, in case you ever use it for that too.
     
  5. aaron.s

    aaron.s Member

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  6. Lloyd

    Lloyd Active Member

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    Here is a slim box that I mounted outside.

    photo123.jpg

    photo1234.jpg
     
  7. Iz

    Iz EVs are here to stay

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  8. neroden

    neroden Happy Model S Owner

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    Because of the RV usage of 14-50s, it's actually really easy to find outdoor-rated receptacles for NEMA 14-50 with suitable enclosures which open from the top and seal up well. There are a lot of different ones available, they're all cheap, my electrician just took one off the shelf. Mine is just plastic with a plastic door.
     
  9. Leon Mege

    Leon Mege New Member

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    If you don't mind me asking -what is the manufacturer's name and the model number of this box?

    - - - Updated - - -

    If you don't mind me asking -what is the manufacturer's name and the model number of this box?
     
  10. Lloyd

    Lloyd Active Member

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    HBL 7777A 2 gang weatherproof cover
    for $44
     
  11. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    To add to Lloyd's reference, the box itself is a standard weatherproof 2-gang available at any home improvement store, the receptacle is a standard 14-50, and the cover is as Lloyd mentions.
     
  12. Leon Mege

    Leon Mege New Member

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    Thank you!!!
     
  13. Matthew Lock

    Matthew Lock Member

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