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GFCI Breaker is Code for EV Charging

Discussion in 'Model Y: Battery & Charging' started by caffeinated, Sep 17, 2020.

  1. caffeinated

    caffeinated Member

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    In preparation for getting our MY we had an electrician install a NEMA 14-50 outlet on a dedicated 50A breaker in our sub-panel. We didn't want to pay a Tesla tax, so we said it was for a family member's RV (which is true) and that we hoped to use it for a future electric vehicle (also true). Today we had the county inspection and we were told that the new code for EV charging requires a GFCI breaker and he signed off on it only for use for the RV. Had I known, I would have had the electrician install a GFCI breaker as I definitely want to be following code and I do think we should have been advised of the new requirement by the electrician. That said, we passed inspection and we have our charging outlet. Should we change it? It is in an enclosed garage and it is hard to imagine that there is any real risk here. Has anyone had issues with a GFCI breaker tripping without cause? I think the company that did the install will correct it upon request, with minimal additional charges. I also have a family member who can do it the next time they visit. Any experience or advice in regards to GFCI breakers for EV charging? Should I correct this, or just use it as is?
     
    • Funny x 3
  2. strider

    strider Active Member

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    #2 strider, Sep 17, 2020
    Last edited: Sep 17, 2020
    Swapping the breaker is trivial, but GFCI breakers are expensive. $100 vs $10. You can grab one at Home Depot and swap it yourself or have your family member do it.

    Square D Homeline 50 Amp 2-Pole GFCI Circuit Breaker-HOM250GFICP - The Home Depot

    I'm used to GFCIs being used in wet locations and I guess a garage could get wet. But there are so many safety features built into EVSEs (that's what the mobile cable is, the charger is in your car) I can't imagine the cable would energize if something was amiss.

    There are tens of thousands of 14-50s being used for EVSEs on standard trip breakers. The only thing you have to weigh is with your homeowner's insurance. Since you now know that you need a GFCI breaker if something were to happen and the car starts a fire the insurance company could try to not cover it.

    If it were me I'd go ahead and have your family member swap it. If it nuisance trips then swap it back and return it to Home Depot. If not then run it with the knowledge that you are code compliant.
     
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  3. qdeathstar

    qdeathstar Active Member

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    Therefore, it is not a tesla tax. Not only did you not pay for the gfci, but also, for an EV, your installer would have also ran 6 awg instead of 8awg, because the charger represents a high continuous load. so while you didn’t pay the “tesla tax” the outlet you installed is not suitable for EV charging.

    Swapping a breaker isn’t trivial, and can result in death or fire if done by improperly trained people.
     
    • Disagree x 8
  4. MY-Y

    MY-Y Member

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    One data point..
    From the Gen 3 HPWC manual: "
    For maximum power output, install a standard double pole 60 amp circuit breaker. Wall Connector
    includes integrated GFCI protection - do not install a GFCI circuit breaker."

    Maybe one is a good idea with the mobile charger? Rocky will know...
     
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  5. GHammer

    GHammer What a long strange trip its been.

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    I wish I knew why they changed the code to require a GFCI on an EV outlet, It makes no sense. If an inspector required me to put in a GFCI breaker the first thing I would do when he left would be to replace it with a regular breaker. There have been numerous reports of nuisance trips caused by the mobile connector testing for ground.
     
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  6. GHammer

    GHammer What a long strange trip its been.

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    8 GA THHN wire is perfectly acceptable for an EV outlet, 6 GA is only necessary if using NM-B (romex).

    Changing a breaker is very easy, anyone with a modicum of electrical knowledge can do it.
     
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  7. caffeinated

    caffeinated Member

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    Family member did our sub-panel which was done with a permit and passed inspection. No concerns on that front. I do want to be in compliance with code for EV charging, and outside of the GFCI breaker, it is. I did a quick internet search and I couldn't find any instances of a person getting injured while charging, so maybe this code change is an abundance of caution for a possible issue that has not yet occurred. So do I change the breaker to meet the new EV code, or just use it as is. Almost as hard as choosing the paint color....
     
  8. jstjohnz

    jstjohnz Member

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    I think it is in 2017 code, moist areas won't have adopted that yet. AFAIK GFCI for EVSE is only needed if the EVSE does not have built-in shock protection ( not sure if that must be GFCI or can just be intrinsically safe by design not allowing contact with any exposed live contacts}.
     
  9. qdeathstar

    qdeathstar Active Member

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    What would happen if the ground fault was on the line side of the ev charger?
     
  10. qdeathstar

    qdeathstar Active Member

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    romex was likely used in a residential setting. And in my house I would definitely want 6 ran for a car charger. Do you have any information to share that would indicate the OP has a “modicum of electrical knowledge”??

    “sure, poke your hands into something that can kill you bro”

    my suggestion to the OP is request your electrician install the gfci breaker for you and you provide it.
     
    • Disagree x 1
  11. Rocky_H

    Rocky_H Well-Known Member

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    Well, congratulations, this did get me to burst out in cackling laughter, so thank you.
    So you intentionally misled him about the purpose of the outlet, but then were miffed and indignant that he didn't out of the blue explain some NEC obscurity about outlets which are installed for a completely different purpose that you didn't tell him about?!?! :eek::p That's rich!

    OK, now, since @MY-Y has invoked my name for remembering this code trivia, yes, this requirement about GFCI's was added into the 2017 version of NEC. I think it's about a little over half of states have adopted that, but many are still on 2014. Here's a really cool map of that:
    Learn where the National Electrical Code® (NEC®) is enforced. | NFPA

    Mostly. The distinction in the code says that any receptable that is being installed for the purpose of EV charging must have a GFCI breaker. Hardwired ones are exempt, because people won't have access to the wires. So that's where that condition does exist where people can be plugging or unplugging and can be exposed to energized prongs. It's not really about devices that don't already have their own built-in GFCI. Tesla's wall and mobile connectors both have internal GFCI, and I think every mobile EVSE does have that, but that is in an electronics box that is farther along the cord, so it protects issues at the charging handle end. But that can't protect if you touch a prong while plugging it into the outlet.

    So it is one of those rare and overprotective things that probably isn't very necessary.
     
  12. caffeinated

    caffeinated Member

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    @Rocky_H.... Glad you find it amusing, and I hope that anyone looking to still looking to install the 14-50 will be aware of a possible code issue if the breaker is not GFCI. We did say it was for a future EV and for a motor home, and both are true. We chose the basic 14-50 outlet as we don't want to be tied into a Tesla charger when we may have a different EV in the future. And it will be used as an RV outlet when family is visiting.
     
  13. Rocky_H

    Rocky_H Well-Known Member

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    If it's for the RV, then it's not violating code. That's one of the things that is so useless and hokey about that provision in NEC. Regulations for things like this should not be based on state of mind or intentions. Those same outlets would have the same plugging in dangers regardless if people are plugging mobile homes into them, but electric car equipment generally has better protection built into it, so if anything, there is less risk or need for GFCI.

    It reminds me of the ridiculous alcohol laws in Utah.

    And sorry, I forgot that you did say that you hinted that it might be used for an EV someday also.
     
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  14. MXLRplus

    MXLRplus Active Member

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    GFCI should not to be used for EVs. There is GFI logic in the EVSE and the car. A third one is just asking for false failure mode.

    You don't have to believe it, you'll end up learning it anyways.
     
    • Like x 2
  15. jstjohnz

    jstjohnz Member

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    I don't think your inspector was correct in approving the receptacle without GFCI and telling you that it would need to be updated to GFCI in the future if you used it for EV charging. I think a receptacle either is or is not code-compliant when it is installed. If it is compliant when installed, it isn't required to be updated later.

    Note: for anyone who has an existing 30 to 50 amp receptacle for EV charging, those receptacles do not require GFCI just because current code requires it, it is based on the code that was in effect in that area at the time of the install.

    The wording has a bit of a built-in loophole, since the GFCI requirement is based on the "intended" use of the receptacle at time of installation. Also this is a NEC 2017 requirement and a lot of areas aren't using 2017 yet.

    This will become a moot point before long since the 2020 code will require GFCIs on all receptacles installed in garages, regardless of intended use.
     
  16. strider

    strider Active Member

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    The OP installed a 14-50, which means they are going to use the Mobile Connector. The latest Mobile Connector will only charge at 32A on a 14-50. 8 awg in all but the cheapest aluminum is PLENTY for a 32A continuous load.
     
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  17. caffeinated

    caffeinated Member

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    Yes, we intend to use the Mobile Connector. We generally drive less than 5,000 miles/year although we expect that to go up a bit now that we are a one car household. And tbh we could get by with the mobile connector and the regular 120V 20A garage outlet. I just didn't like the idea of 300 watts going to keeping the computers running for hours while the charging was happening. The cost of installing the outlet is more than the cost of the electricity we'll save with faster charging, but the inefficiency would drive me crazy. With the 32A charging it will run less than an hour most nights. Plus we will have some flexibility going forward. I have long admired Tesla and the advances they have made with electric cars, although I never expected to buy one. When there are more choices out there for an AWD EV with decent range and some towing capacity, it is possible we might choose differently.
     
  18. qdeathstar

    qdeathstar Active Member

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  19. qdeathstar

    qdeathstar Active Member

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    I would want #6, and we havnt even discussed voltage drop. You are conflating minimum code requirements with best practices.


    14 awg with stablock connectors meets code for bedroom living rev but it’s chincy AF
     
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  20. Rocky_H

    Rocky_H Well-Known Member

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    Just stop. That wall connector with 14-50 plug has been gone and discontinued for over a year. It is not available.
     
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