TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker and becoming a Supporting Member. For more info: Support TMC
Start a Discussionhttps://teslamotorsclub.com/tmc/tags/

Need help determining if I can use the charger in my garage

Discussion in 'Charging Standards and Infrastructure' started by ChrisH, Feb 10, 2018.

  1. ChrisH

    ChrisH Member

    Joined:
    Jun 4, 2013
    Messages:
    161
    Location:
    Milton, wa
    Hello all.

    A couple of years ago, we had a house built and an electric car charger was an add on option so we went for it. I did not know anything about electric car charging back then so I think I may not have the best set up for charging a model 3 when I eventually get one.

    What was installed is a NEMA 6-50. Should be good right? Well, it looks like it has its own circuit, but was installed with only a 40amp breaker and what I think is 8 gauge wiring. Tesla’s guidance seems to be that a 6-50 should have a 50 amp breaker and be installed with 6 gauge wiring. I believe some of the charging systems such as the Watt Station only needed the type of set up that was installed in my garage.

    Can I still use this outlet, but dial down the the amp draw to 32 amps to be safe or am I out of luck because the gauge wiring is incorrect in addition to the breaker?

    Here is a pic of my electrical box. Not a great picture, but the wiring for the 6-50 is the second set of two breakers on the left hand side.I’m guessing that’s only 8 gauge?

    [​IMG]

    We also have a NEMA 14-30 in our garage (because we had washer and dryer outlets roughed in as well) so I might be able to use that, but I’d really like to use the electric car charger we paid for if at all possible.

    Any guidance would be much appreciated!
     
  2. AEdennis

    AEdennis Active Member

    Joined:
    Jul 23, 2013
    Messages:
    2,320

    If you have the new UMC that only draws 32a on the NEMA 14-50 and 6-50
     
  3. Lloyd

    Lloyd Well-Known Member

    Joined:
    Jan 12, 2011
    Messages:
    5,494
    Location:
    San Luis Obispo, CA
    Use the 6-50 at 32 amps. You will find that it is sufficient.
     
  4. ChrisH

    ChrisH Member

    Joined:
    Jun 4, 2013
    Messages:
    161
    Location:
    Milton, wa
    Thanks guys...it’s okay to do that even with the smaller wiring and breaker?

    I guess if I get the SR Model 3 it only comes with a 32amp on board charger anyway right so it should all be safe?
     
  5. fasteddie7

    fasteddie7 Member

    Joined:
    Aug 12, 2016
    Messages:
    453
    Location:
    uniontown PA
    8 gauge should handle 32a just fine and your 40a breaker falls under the 80% rule when charging at 32a. You should be a-ok
     
  6. BerTX

    BerTX Active Member

    Joined:
    May 2, 2014
    Messages:
    2,346
    Location:
    Texas/Washington
    Just to help out in the future -- the NEMA 6-50 is a receptacle, not a charger. The charger built into the car, your Mobile Connector connects the receptacle to the charger in the car. It is a little confusing to call the receptacle a charger, just like someone might be confused if you pointed to an outlet in the kitchen and called it a toaster.

    You will need to get an adapter for your NEMA 6-50 receptacle from Tesla for $35 to plug in the Mobile Connector.

    Model 3 NEMA Adapters
     
  7. ChrisH

    ChrisH Member

    Joined:
    Jun 4, 2013
    Messages:
    161
    Location:
    Milton, wa
    Thanks for the clarification. The builder just called it an electric car charger and installed it in the garage haha.

    Glad to hear the 6-50 should work and thanks for the reminder about needing the adapter!
     
    • Like x 1
  8. swaltner

    swaltner Member

    Joined:
    Oct 13, 2012
    Messages:
    759
    Location:
    Kansas, USA
    Also, contact your builder and let them know that if they're going to offer a "car charger" as an option on new house builds, they should do it "right". They might want to install a NEMA 14-50 outlet in the garage (would require an extra wire for neutral, which is why they did a 6-50 outlet instead of the 14-50) but they really should be using 6 gauge wire and a 50 amp circuit breaker. The NEMA 14-50 is the low-cost option that has the most wide spread use on EVs, mostly because it's widely deployed at RV parks. Installing the proper wire and circuit breaker avoid issues when charging cars like the Tesla Model S, which would attempt to draw 40 amps continuous and be unsafe on your setup.

    However, as mentioned, you won't have a problem charging your Model 3.
     
  9. ChrisH

    ChrisH Member

    Joined:
    Jun 4, 2013
    Messages:
    161
    Location:
    Milton, wa
    Absolutely. When I started looking into Teslas I was upset to learn it was a 6-50 and not a 14-50 and then was more upset to learn it only had a 40 amp breaker. My fault for not doing research prior to paying for something though!
     
  10. TexasEV

    TexasEV Well-Known Member

    Joined:
    Jun 5, 2013
    Messages:
    5,508
    Location:
    Austin, TX
    Some 30 or 32A J1772s are made to plug into a 6-50 outlet. Maybe the builder was saying it was EV charger ready (actually EVSE ready) rather than the charger itself?
     

Share This Page

  • About Us

    Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.
  • Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


    SUPPORT TMC