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/

Rate of charge at using a NEMA 14-50 outlet

Discussion in 'Model X: Battery & Charging' started by volkerbradley, Jun 24, 2016.

  1. volkerbradley

    volkerbradley Member

    Joined:
    May 29, 2013
    Messages:
    78
    Location:
    United States
    I've made arrangements to charge my P90D at a campground in the Upper Peninsula of Michigan. They have NEMA 14-50 plug.
    If my battery is at 20% when I start charging and I plug in at my Tesla 80 AMP home charger, the display states that the charging rate is about 41 miles/hr.
    If the car battery is 20% when I start charging, what would the charging rate be at a 50 AMP connector at a campground?
     
  2. Joe Harsanyi

    Joe Harsanyi Member

    Joined:
    Jun 23, 2015
    Messages:
    40
    Location:
    Pasadena, MD
  3. eye.surgeon

    eye.surgeon Active Member

    Joined:
    Nov 18, 2014
    Messages:
    1,000
    Location:
    California
    Yes it will be aprox 30 mph. That's my set-up at home. Keep in mind a 50 AMP connector is going to actually put out 40 AMPs.
     
  4. MorrisonHiker

    MorrisonHiker S 90D 2017.50.3

    Joined:
    Mar 8, 2015
    Messages:
    3,621
    Location:
    Colorado
    I'm assuming the OP is asking about an X, not an S since this was posted in an X forum and they have a Sig X listed in the signature.

    From Home charging installation:
     
  5. rypalmer

    rypalmer Member

    Joined:
    Aug 22, 2014
    Messages:
    760
    Location:
    Canada
    Slower in Canada unfortunately. In Canada the 14-50 connector is limited to 32 amps continuous, 80% of what it will do in the US.
     
  6. TexasEV

    TexasEV Well-Known Member

    Joined:
    Jun 5, 2013
    Messages:
    5,429
    Location:
    Austin, TX
    Also know that battery state of charge doesn't matter with AC charging as it does with a supercharger. The 25 miles/hr for an X or 29 miles/hr for a S is if you're charging from a 14-50 at the full 40A. At many campgrounds the wiring isn't good enough to sustain 40A and you have to set the charging to a lower amperage, maybe 30A. You can calculate the charge rate ahead of time based on the ratio, or it will be displayed on the screen.
     
    • Informative x 1
  7. Evbwcaer

    Evbwcaer Member

    Joined:
    Jun 21, 2014
    Messages:
    535
    Location:
    Minnesota
    So an X on a 14-50 in Canada would be only charge about 20 miles of range per hour?

    (25mph/40amps = 20mph/32amps)
     
    • Like x 1
  8. SabrToothSqrl

    SabrToothSqrl Active Member

    Joined:
    Dec 5, 2014
    Messages:
    2,084
    Location:
    PA
    Great... now I have to ask... why is it slower in Canada if it's the same connector?
     
  9. eye.surgeon

    eye.surgeon Active Member

    Joined:
    Nov 18, 2014
    Messages:
    1,000
    Location:
    California
    US mandates a 20% reserve from rating to output for safety, hence 50amp rated outputs 40amps. Canada for whatever reason mandates more of a safety buffer. Maybe because they're more polite.
     
    • Funny x 4
    • Informative x 1
    • Love x 1
  10. Evbwcaer

    Evbwcaer Member

    Joined:
    Jun 21, 2014
    Messages:
    535
    Location:
    Minnesota
    So how does Tesla comply with this limiting?

    If a Canadian Tesla comes to the US, will it pull 40a from a 14-50?

    Just wondering how this is implemented: umc, car's home, gps?
     
  11. MorrisonHiker

    MorrisonHiker S 90D 2017.50.3

    Joined:
    Mar 8, 2015
    Messages:
    3,621
    Location:
    Colorado
    I believe that the resistor in the 14-50 adapter is different.

    This thread should have all the details that were discussed last fall: New UMC?
     
  12. umeshunni

    umeshunni Member

    Joined:
    Jan 4, 2016
    Messages:
    391
    Location:
    San Francisco, CA
    Well, once you convert it back into kmph, it all works out (32kmph/32amps) :)
     
  13. Evbwcaer

    Evbwcaer Member

    Joined:
    Jun 21, 2014
    Messages:
    535
    Location:
    Minnesota
    I read through MorrisonHiker's linked thread. If I was in Canada I would buy a US spec 14-50 UMC adapter and use it whenever I can confirm a 50 amp breaker is serving the outlet.
     
  14. rypalmer

    rypalmer Member

    Joined:
    Aug 22, 2014
    Messages:
    760
    Location:
    Canada
    Probably something about most NEMA 14-50 outlets being on 40 amp circuits instead of 50 amps. Just speculating.
     
  15. ccutrer

    ccutrer Active Member

    Joined:
    Sep 3, 2015
    Messages:
    1,154
    Location:
    Saratoga Springs, UT
    My X is charging at 40A, 236-240V, 26mph on my 50A breaker, 6-3NM 14-50.

    Hmmm.... a 14-50 adapter that automatically limits to 32A? That would be perfect for the 14-50 at my parent's house on a 40A circuit with 8-3NM.
     
  16. volkerbradley

    volkerbradley Member

    Joined:
    May 29, 2013
    Messages:
    78
    Location:
    United States
    Thank you for the information
     
  17. gfb107

    gfb107 Member

    Joined:
    Sep 3, 2015
    Messages:
    184
    Location:
    Cary, NC
    Brought out Model X 75D home last night, and plugged it into out 14-50 outlet. It was at ~50% charge, both the in-car screen and the iPhone app showed it was charging at 28mi/hr.
     
  18. TexasEV

    TexasEV Well-Known Member

    Joined:
    Jun 5, 2013
    Messages:
    5,429
    Location:
    Austin, TX
    That's what is expected, 28-30 mph depending on what voltage the car actually gets (240V isn't always exactly 240V). The SOC does not affect AC charging rate as it does with supercharging-- until the very end at 98% or so.

    In car screen and iPhone app will always say the same as they're reporting from the same data source.
     
  19. volkerbradley

    volkerbradley Member

    Joined:
    May 29, 2013
    Messages:
    78
    Location:
    United States
    I charged at that campground. I noted that it charged at 22 mph.
     

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