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NEMA 16-20 @ 16 amps?

Discussion in 'Model S: Battery & Charging' started by Stasla, Apr 16, 2016.

  1. Stasla

    Stasla Member

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    I have a 20 amp NEMA 16-20 outlet relatively near the driveway. From what I can gather, one can order a 16-20 to 15-20 adapter from evseadapters.com ($59 + shipping) and should theoretically be able to pull 16 amps from that outlet, as long as the car is dialed down to that amperage. Anyone with real life experience with this setup?
     
  2. Stasla

    Stasla Member

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    #2 Stasla, Apr 16, 2016
    Last edited: Apr 16, 2016
    Not able to edit OP for some reason...

    Of course I meant 6-20 and 5-20, not 15/16-20 (damn you, autocorrect!)

    Also forgot to mention that the EVSE adapter would be used with a NEMA 5-20 Tesla adapter and UMC in this scenario.

    So: 6-20R => 6-20P..(EVSE adapter)..5-20R => 5-20 Tesla Adapter => UMC.

    Any feedback on pros/cons/risks of this solution as a daily charging setup would be greatly appreciated.
     
  3. TexasEV

    TexasEV Active Member

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    You don't need to dial the amperage down. The UMC 5-20 adapter will automatically draw 16A maximum. That's the advantage of this setup using a native UMC adapter. This is a great solution if you already have a 6-20 outlet and don't need to charge faster than about 12 mph.
     
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  4. linkster

    linkster Member

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    All yups! :) And it is one of the reasons why I believe all owners should own this versatile/muti-purpose
    5-20 UMC adapter. I will also deploy an unmodified 5-20 terminated 50' 12awg extension for 240 or 120v charging that requires no manual amperage adjustment for safe charging if my 50' UMC wont reach.
     
  5. Stasla

    Stasla Member

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    #5 Stasla, Apr 16, 2016
    Last edited: Apr 16, 2016
    Your UMC is 50' ?! Is that a mod? I thought it came with a 20 foot cable.

     
  6. Stasla

    Stasla Member

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    Another thought, and this may be a bit more risky, why not just wire the 5-20r outlet into the 240v instead of the 6-20r one and cut out the EVSE adapter altogether. I realize it will fry any 120v appliance inadvertently plugged into it, but with lots of labeling it could work! Am I missing something?
     
  7. linkster

    linkster Member

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    #7 linkster, Apr 17, 2016
    Last edited: Apr 17, 2016
    Will work, but a very bad/unsafe strategy all around IMO.

    Unless you need the extra ~3mph charge rate, I would just deploy the Tesla 6-15 UMC adapter as it will still provide you
    with a 1/2 tank ;) overnight without the hassle of using 3rd party adapters that add additional failure points. I have not seen any (not that they don't exist) NEMA 6-20 receptacles that don't accept 6-15 plugs.

    These guys "stretched" my UMC to 50' in 2 days.

    Tesla UMC extension
     
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  8. tga

    tga Active Member

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    How does it look when they are done? Are there obvious splices in the cable? Do they extend the existing cable, or replace it in its entirety, giving you a longer, splice-free UMC?
     
  9. MorrisonHiker

    MorrisonHiker Beta Tester

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    I guess you haven't seen an L6-20 receptacle? ;)
    [​IMG]

    I have one of those in my garage in addition to two 14-50 outlets. I don't plan on using it until a third Tesla is parked on the garage. Now that the new HPWC is out which can balance the load, I may end up going that route instead and remove the L6-20.
     
  10. linkster

    linkster Member

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    Actually, I am quite familiar with the "L" series (twist-lock line). The OP stated that he/she has a NEMA 6-20 receptacle with no mention of any "L" wiring device.
     
  11. MorrisonHiker

    MorrisonHiker Beta Tester

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    Ah ok. You had mentioned
    so I was thinking you meant any 6-20 receptacle wouldn't require adapters. I guess you were just referring to a regular 6-20 and not the L subset.


    It would be nice if Tesla offered a wider range of adapters for the UMC.
     
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  12. Stasla

    Stasla Member

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    That's right a non-locking 6-20r

     
  13. James Anders

    James Anders Member

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    So that's what I have is a 6-20 (i believe) with a 2 ganged 20A breakers. So what are the options here (other than getting new 14-50 wiring and receptacles)?

    IMG_7890.jpg
     
  14. linkster

    linkster Member

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    #14 linkster, Apr 18, 2016
    Last edited: Apr 18, 2016
    Option 1 (safe, recommend)
    Purchase the $45 Tesla 6-15 UMC adapter that will charge at [email protected] and provide ~9mph charge rate on an S (probably 1-2 additional on a ☰)

    Option 2 (safe, recommend)
    Install an HPWC and set the dip switches for 16/20 amp charging

    Option 3 (safe)
    Install appropriate EVSE equipment.

    Option 4 (not recommended as a long-term solution)
    Deploy a custom 6-20P -> 5-20R (BUT wired w/L1+L2 and ground) along with Tesla's 5-20 UMC adapter that will charge at [email protected] and provide ~12mph charge rate on an S (probably 1-2 additional on a ☰)

    Charging from NEMA 6-20 using NEMA 5-20 Adapter

    Good-Luck!

    btw, for option 1, I would rotate (after de-energizing said branch circuit, of course!) the 6-20 receptacle 90 degrees to relieve the cable/brick strain (for some reason the 6-15 UMC adapter does not align with UMC cable as all the others)
     
  15. linkster

    linkster Member

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    #15 linkster, Apr 18, 2016
    Last edited: Apr 18, 2016
    There are 2 splices. The splices are extremely durable/strong as they are protected by thin ridgid sleeve that is double sealed with adhesive and an outer shrink sleeve for what appears to be stronger than the cable itself attaching points that are waterproof. I have owned this slick professionally assembled fifty-footer for around 2 years and I keep it in the car and deploy a stock length UMC permantly docked on a 14-30 for over 3 years with 80 and 160-mile commutes.
     
  16. tessnme

    tessnme Member

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    I purchased the Tesla 6-20 adaptor and changed one of the plugs in the garage to 6-20. The plug was on a 20 amp breaker and had 12 gage wire, so I should be OK. Even though the car says it's charging at 16 amps on this circuit, I'm getting the same 4 mph charge rate as I did with a 12 amp charge. Using the time to completion, I figure I'm getting a little over 4 mph instead of a little less than 4 mph, but I was expecting better.
     
  17. linkster

    linkster Member

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    tess

    I think you mean a 5-20 as Tesla has never offered a 6-20 UMC adapter and your charge rates are more in line w/120v charging.
     
  18. AWDtsla

    AWDtsla Active Member

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    The mph indicator does not reflect actual values for slow charging unless you've been charging for 8-10 hours, it's just a poor algorithm for the display.

    If the car reports 16A, then it is charging faster.
     
  19. James Anders

    James Anders Member

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    Would the following be an option? Thanks a lot by the way.

    NEMA 14-50R to 6-20P Adapter
     
  20. Stasla

    Stasla Member

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    That's the one I was talking about at the top of the thread.:cool:

     

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