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Replace a 15-50 with HPWC?

Discussion in 'North America' started by brkaus, Jan 14, 2017.

  1. brkaus

    brkaus Active Member

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    Can I remove a 15-50 and replace with an HPWC? Of course, switches would need to be set for appropriate circuit capacity and charge at 40A.

    I read the HPWC manual and said must be connected with non flammable conduit.

    Is a face plate with a short conduit stub into the back of the WC appropriate?

    Looking for a cheaper way to get going, but eventually have the longer cable wall connector.
     
  2. Craig-Tx

    Craig-Tx Member

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    DISCLAIMER: NOT A LICENSED ELECTRICIAN

    As for the non flammable conduit, I believe that means if using conduit, it must be conduit meant for electrical.

    If this is in a garage, or other area where weather isn't a direct concern, I don't believe conduit is required. As long as the physical wires are long enough to reach out of the box and into the HPWC, and as long as they can be physically protected from damage (i.e. not exposed and not able to be cut / scraped during install) then you should be fine.

    I would also check the type of wire. Depending on the gauge and wire type, you may be able to bump up to a 60 amp breaker to make use of up to a 48 amp charge rate. (It's a possibility, but likely you'll still be limited to a 50 Amp circuit.)

    Of course your local jurisdiction may have other requirements.
     
  3. brkaus

    brkaus Active Member

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    Thanks! I'm not a licensed electrician either, and I will have an electrician install. I'm trying to be forward thinking - install cheap but prep for the "easy" upgrade.

    Good point on the 60A upgrade. From the tables, it looks like 6 Ga THNN in conduit will serve 60A. Instructions say it is supposed to be wired with 6, so I'll have to make sure.
     
  4. Rocky_H

    Rocky_H Active Member

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    I'm not sure from the apacity tables if you can go to a higher level circuit. I would probably just keep it as the same 50A circuit just to keep it simple. By the way, it's a 14-50 outlet, not 15-50.
    As to changing out the install, you wouldn't necessarily need to do any conduit. The wall connector can be mounted right over top of where the outlet was.
    Also, regarding wiring, a 14-50 has four wires: hot1, hot2, neutral, and ground. The neutral isn't being used by the Tesla charging system, but electric code requires it to be there for a 14-50 outlet. The wall connector won't need the neutral and doesn't have a place to connect it, so you just need a cap on that wire to keep it covered.
     
  5. MorrisonHiker

    MorrisonHiker S 90D 2017.28 c528869

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    NEMA 15-50 does exist. I think 14-50 would be most likely in a residential install...but there's a possibility it could actually be a 15-50 outlet.
     
  6. Cosmacelf

    Cosmacelf Active Member

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    A 15-50 is a 3 phase outlet. Very unlikely to be installed in a residential garage, and cannot be used to charge a Tesla without an interesting home made adapter, so yes, thinking it is a 14-50.
     
  7. MorrisonHiker

    MorrisonHiker S 90D 2017.28 c528869

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    Yeah, that's why I mentioned residential. OP didn't mention if it was residential or commercial. It's most likely 14-50 but I just wanted to point out that 15-50 does exist.
     
  8. Jlwine

    Jlwine Member

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    When I had the electrician install my 14-50 last year I had him run proper gauge wiring so--as I did at a later date, I could swap it out with a 60 AMP breaker and install the HPWC to charge at 48 AMPS. Tesla provides clear instructions and the installation was simple. I really like the HPWC, the short cord and design make for a much cleaner install and of course allows me to always have my mobile charger with me.
     
  9. brkaus

    brkaus Active Member

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    Yes, residential. I messed up my numbers - planning on a 14-50. Thanks for the correction.

    My conduit question comes from the updated manual for the WC that states -
    • Conduit openings are sized for 1" (25 mm) conduit.
    • Conduit needs to be metal and fame retardant.
    • Use an appropriate circuit breaker.
    I'll talk to my electrician about sizing for possible future upgrade. I do think sizing for 60A breaker may be a good idea with the 48A chargers on the cars now.

    Appreciate the comment on the neutral wire as well. Totally forgot about that part. Wire cost probably isn't that much, so I think I'll still go the 14-50 first. Maybe never need the WC.
     
  10. Saghost

    Saghost Active Member

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    If it helps your decisions/planning, keep in mind that there's no technical reason an HPWC can't have a 14-50 plug wired on to it and get plugged in (with appropriate amperage settings, of course.)
     
  11. FlatSix911

    FlatSix911 918 Hybrid

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    Great idea ... :cool:

    IMG_3843.JPG
     
  12. Craig-Tx

    Craig-Tx Member

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    Even if installing ONLY a HPWC, I would pull a Neutral. The wire cost is minimal, and it helps to future proof the install such that if you ever move or get a different vehicle, you can remove the HPWC and put a NEMA 14-50 or other EVSE in its place.
     
  13. Rocky_H

    Rocky_H Active Member

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    I personally wouldn't see any benefit to that. If you do get a different electric vehicle, you could still get a different J1772 EVSE that is hardwired, so those still will not need a neutral wire. The only reason for a neutral is if you need to make it an actual outlet. Those 14-50 and 14-30 outlets are supposed to have a neutral to be code compliant, but electric car charging never needs the neutral, so why bother with putting in the outlet on purpose instead of hardwired? It kind of seems like the cart pushing the horse. They sell those J1772 stations with plugs so that if there is an outlet already existing some place, you can just buy that and use it without needing to get an electrician, but intentionally putting in an outlet and an EVSE with a plug just seems like putting an unnecessary hurdle in front of yourself.
     
  14. miimura

    miimura Active Member

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    Also, many of the EVSEs that do come with a cord, use a 6-50 instead of a 14-50 because the neutral is not used.
     
  15. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    The wiring will be in the house forever, but the current owner may not be. Best to have a proper installation that can be repurposed later. Also, having a 14-50 and HPWC (with a switch so that only one could be used at a time) will provide redundancy (HPWCs can break).
     
  16. Rocky_H

    Rocky_H Active Member

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    It IS a proper installation! Most people don't need to plug in a mobile home or RV into their garage, so why would a 14-50 outlet be the only "proper" thing? The hot/hot/ground wiring being available at the wall is all that is necessary for any kind of future car charging station. I don't see the point in extra expense to try to guess what a future hypothetical owner of the house might want.
    This is the valid point. If you want redundancy in case your wall connector dies, that's a fine idea. Depends on what other backup plans you have available.
     
  17. brkaus

    brkaus Active Member

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    Turns out my utility pays for part of the install. So no reason to not get the HPWC from the start. Going to have oversized conduit put in so I can easily upgrade in the future.
     

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