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Rate of charge at using a NEMA 14-50 outlet

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

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  1. volkerbradley

    volkerbradley Member

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    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

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  3. eye.surgeon

    eye.surgeon Member

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    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 Beta Tester

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    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

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    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 Active Member

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    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.
     
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  7. Evbwcaer

    Evbwcaer Member

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    So an X on a 14-50 in Canada would be only charge about 20 miles of range per hour?

    (25mph/40amps = 20mph/32amps)
     
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  8. SabrToothSqrl

    SabrToothSqrl Active Member

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    Great... now I have to ask... why is it slower in Canada if it's the same connector?
     
  9. eye.surgeon

    eye.surgeon Member

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    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.
     
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  10. Evbwcaer

    Evbwcaer Member

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    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 Beta Tester

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    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

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    Well, once you convert it back into kmph, it all works out (32kmph/32amps) :)
     
  13. Evbwcaer

    Evbwcaer Member

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    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

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    Probably something about most NEMA 14-50 outlets being on 40 amp circuits instead of 50 amps. Just speculating.
     
  15. ccutrer

    ccutrer Member

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    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

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    Thank you for the information
     
  17. gfb107

    gfb107 Member

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    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 Active Member

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    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

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    I charged at that campground. I noted that it charged at 22 mph.
     

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