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Options to Charge from a NEMA 6-30 Plug?

Discussion in 'Model S: Battery & Charging' started by Black/Black MS, Oct 17, 2016.

  1. Black/Black MS

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  2. gregd

    gregd Member

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    Probably would work, but I expect the circuit's only got a 30 amp breaker (the "-30" in the connector type), not the 50 amps which the 14-50 socket is usually rated for. Since it's only safe to pull 80% of the rated load, be sure to tell the car to charge at no more than 24 amps. Pulling 40 amps (80% of a 14-50 socket) could be very bad.

    I charge from a 10-30 plug (old style dryer), and do something similar. 24 amps isn't all bad, if the alternatives are worse.
     
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  3. Alketi

    Alketi Member

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    There are better values for 14-50 extension cords if you make your own, but yes, that combination would work. Set your car to charge at 24A as @gregd mentioned.
     
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  4. Black/Black MS

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    Cool. How many miles per hour of charge do you get?
     
  5. Brass Guy

    Brass Guy Member

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    That will work, dial back the current as mentioned above, and it's probably what I'd do. But a better way would be to get a Tesla 14-30 adapter for your UMC and make a 6-30p to 14-30r adapter.

    I think Tesla made a 6-30 adapter early on. If they did it'd be tough to find one now.
     
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  6. gregd

    gregd Member

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    You know, I've never actually measured it... Always just plugged it in and went about my business.

    Based on the logs, it looks like about 18 mi/hr or so. Last charge was about 45 miles worth in 2.5 hours, but not sure how much of that was tapered. SOC went from 65% to 83%, 321 wh/mi for the charge. This is for a Roadster 2.0, if that helps.
     
  7. miimura

    miimura Active Member

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    Tesla made a 6-50 adapter when the Model S was first introduced, never a 6-30 for the Mobile Connector.

    The best solution for the OP is: Mobile Connector -> Tesla 14-30 Adapter -> 14-30 socket -> 8-3 SOOW cable -> 6-30 plug. This cable needs to be marked "Tesla Charging Only" because the Neutral will be open and it could damage any other equipment that might be plugged into the 14-30 socket. The Tesla Mobile Connector does not use the Neutral.
     
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  8. Black/Black MS

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    That's actually pretty good. About 5x what I get plugging into a regular outlet.
     
  9. Black/Black MS

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    Very interesting. So I buy the 14-30 adapter, then I essentially build my own extension cord with a 14-30 receptacle on one end and a 6-30 plug on the other?

    If I do it this way do I still need to manually manage the amps or will the car automatically draw the right amount of power?
     
  10. Rocky_H

    Rocky_H Member

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    No, you won't need to manually dial it in; that's why this is recommended. The physical Tesla-branded adapter tells the cable and the car what amp level to limit to. If you are using a Tesla 50A piece, but converting it to a 30A plug with a separate pigtail, the car can't see that, and it will think there is a 50A circuit there. You can manually adjust it down, but then if something glitches or resets it might try to pull 40A from that 30A circuit. In a good case, it would flip the breaker, but if the breaker malfunctions, that's very bad.

    This is why they are recommending making an adapter from an official Tesla 30A to a different 30A plug. It will automatically have it limited to the right level.
     
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  11. Rocky_H

    Rocky_H Member

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    Informative side note: That's why this was shortsighted/dangerous/stupid that Tesla had discontinued all of their adapters that were at the 30A level. There was no way to have an adapter to 6-30, 10-30, 14-30, TT-30, etc. that would properly limit the current. Thank goodness they finally got enough of an earful to make the 14-30 again.
     

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