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Nema L6-20 receptacle

Discussion in 'Model 3: Battery & Charging' started by ralph142, Oct 4, 2019.

  1. ralph142

    ralph142 Member

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    My wife and I were looking at a new house and I found existing leviton L6-20 receptacles in separate garage bays (an upper and a lower). These are the single, three prong twist locks. They are apparently both set on a pair of ganged 20 amp breakers, (at least thats the only ganged 20 amp breaker), marked "garage 240 v". All the other garage outlets are 5-15s but on single 20 amp breakers. This seems like an odd set up, but perhaps they were thinking no one would be welding in both bays at the same time ? Both are very long runs from the panel. There is also a 50 amp circuit to the upper garage, which had a 14-50, but it got reused for an AC / heatpump.

    A 240 v 20 amp circuit would be fine for charging my MR, but we're thinking of a Y eventually and that level of charging would be fine too, but not one car at a time. I can't really go back and take the panel apart at this stage, so I'm just more curious about possible solutions than anything.

    So two questions:
    1.) Looks like a single circuit, can they both be used simultaneously ? I would sure guess: no.
    2.) could I just swap the single L6 out for a single 6-20r or is there a l6-20 to 6-20 adapter that would allow me to use the umc ?
     
  2. davewill

    davewill Active Member

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    #2 davewill, Oct 4, 2019
    Last edited: Oct 4, 2019
    Do they both run all the way back to the panel? if so, you could move one of them onto a second breaker giving you two separate circuits. However, I doubt that they do. Your options are pretty limited short of running more wire back to the panel.

    You can certainly change the outlets out for 6-20s, which is what I would do rather than use an adapter, although those are readily available. As you say, that would work fine for one car. For handling two cars, the only thought I have is that you could install two wall connectors and have them share the single 20a circuit. That way the cars could both be plugged in and eventually get charged. Can't really say I recommend it as it would be too slow unless your charging needs are very low, or one of the cars could charge mostly during the day and the other at night or something.

    You'll probably have to bite the bullet and run a new circuit when you get the second car.
     
  3. ralph142

    ralph142 Member

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    thats my guess, a single circuit, I can't really go back and open up the panel stealthily, lol.
     
  4. davewill

    davewill Active Member

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    Why do you have to be steathy? If you're at all serious about buying the house, they should be happy to have you check it out. The simplest test would be to turn off the breaker and test the outlets to see if both go off. You might even find that the wire is bigger than you thought and the breaker could be upgraded or the AC doesn't really need 50a and you could swap the circuits or something.

    Another thought would be to pay an electrician check it out, and give you a quote on running a larger circuit to the garage while he's there. Then you'll have an idea of what it will take later on.
     
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  5. ralph142

    ralph142 Member

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    mostly not worth the time at this point. If we become more serious I'll certainly pursue it or get an electrician to look.
     
    • Informative x 1
  6. ewoodrick

    ewoodrick Well-Known Member

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    Or maybe they just prewired and that's what was used as a plug.
     
  7. user212_nr

    user212_nr Active Member

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    Its probably not difficult to replace the wire. What you probably have is the outlet that is closest to the breaker receives the line, then the second outlet is wired to the first outlet (as most outlets have 2 sets of screws, one for power IN and the other for daisy-chaining).

    So, you can either double up the wire to the first outlet and join it to the second, or you can do full remodel w/ sub-panel. Model Y is a long way off BTW, Elon Time. More important to check is how much power (AMPs) does the house have at the main panel, and how many are free, how many free breaker slots.

    It probably a small concern though, as the other houses you are looking at probably will have no 240v power at all in the garage, unless they have sub-panel.
     
  8. Rocky_H

    Rocky_H Well-Known Member

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    I'm surprised no one has given you the link for this yet. This company called EVSEAdapters makes adapters for about every kind of outlet that Tesla doesn't make officially. Here is their adapter for an L6-20 outlet.
    L6-20 Adapter for Tesla™ Model S™/X™/3™ Gen 2 – EVSE Adapters
     
    • Like x 1
  9. ralph142

    ralph142 Member

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    I saw that, but even a hospital grade 6-20 r is only $20, not 55. I did get the agent to confirm it’s once circuit.
     
  10. Rocky_H

    Rocky_H Well-Known Member

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    :rolleyes: Perhaps I can spell it out a little bit. Each one of these starts as an official Tesla adapter that they have to order and pay for. Then, they hand build each one, where they have to take it apart to preserve the temperature sensing chip in the plug end of it and mount it into their new plug assembly that they are putting onto it. So it's the full price of a Tesla adapter PLUS a pretty decent amount of someone's skilled time that you are paying for.
     
  11. user212_nr

    user212_nr Active Member

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    Yes, but the outlet is only $10-$15 and < 1 hours time to install it. He'll take the $75 / hr for himself I think.

    If he doesn't have the 6-20 adapter though, he would be $35 closer to the EVSE.
     
  12. ajdelange

    ajdelange Banned

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    No need to open the panel. Flip that ganged 20 A breaker and then poke at each of the outlets with a NCV tester. Really no need to even do that as the presence of only one ganged breaker in the panel says that there is only one 240 V circuit.
     
  13. eladts

    eladts Member

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    Doesn't the NEC requires that all 240V circuits are dedicated? I thought daisy-chaining multiple outlets to a single circuit is only allowed with 120V circuits.
     
  14. user212_nr

    user212_nr Active Member

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    What I can find on the web says no. Nothing special about 240v that would make that needed.

    nec 240 daisy chain at DuckDuckGo
     
  15. ralph142

    ralph142 Member

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    This is what I thought was so odd, why daisy chain such a specific circuit, presumably for a welder or some other major tool. Easy to image wanting a table saw and a welder. Doesn’t seem worth not running a second circuit, especially when new construction.
     
  16. ajdelange

    ajdelange Banned

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    Not so easy to imagine using them at the same time. Clearly the most basic 120V branch circuit with multiple outlets makes it possible to overload the circuit by a factor of n if there are n outlets but the code permits this based on the probability of this happening being exceeding small and if it does happen that's what the breaker is there for.
     
  17. ralph142

    ralph142 Member

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  18. ralph142

    ralph142 Member

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    Agreed, but one doesn’t often find one circuit spread thru rooms in widely separated parts of the house. Distance to link upper and lower garage bays ~= distance from panel to lower bay. So, they saved the cost of a breaker and not much wire. High end house built in the 90’s, lots of panel space.
     
  19. Rocky_H

    Rocky_H Well-Known Member

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    Oh, I just realized what I was overlooking. I thought Tesla didn't sell a 6-20 adapter. I thought they just had the 6-15, so it wouldn't be able to access the full current level, so would require some kind of extra adapter anyway.

    But I just checked, and since Tesla does offer a real 6-20, then yes, the obvious solution is to just change the outlet from the locking type L6-20 to the regular 6-20. Sorry I didn't pick up on that the first time.
     
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