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Y connector to combine 2 campsite 14-50s?

Discussion in 'North America' started by Ceilidh, Oct 5, 2012.

  1. Ceilidh

    Ceilidh Member

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    Hey all. I am relatively new to this forum. I tried looking for an answer to this question in the other posts but could not find anyone referring to what I asking about. Forgive me if I just missed it.

    The fact that it has not been discussed may mean that this is a silly question, but here goes:

    I have seen much discussion about RV site plugs when taking extended trips and how to most effectively use them. Many have rigged special plugs to increase draw and decrease charging time (particularly in the Roadster forums).

    One thing I have never seen discussed is trying to simultaneously draw off of 2 RV sites. I am picturing an adapter that splits one NEMA 14-50 plug into 2, and an extension cord to the second plug for situations where the sites are not terribly far apart. Is this worth discussing or just useless?

    I don't really recall how my physics 101 relates to these RV plugs in the real world, and I'm trying to figure out creative ways to minimize charge time on longer trips with my Model S when it arrives.

    For those interested, it is P912. Supposed to come in November but we will see.

    I do realize all the supercharger hype and am looking forward to them. I'm just thinking that although it is often nice to take a break and enjoy nature in the middle of nowhere from time to time, there are other times when you just need to get someplace fast. I would much rather do it on sunlight, or any percentage of something other than gasoline/oil.

    Thanks for any thoughts.
     
  2. Lloyd

    Lloyd Active Member

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    No comment!
     
  3. mnx

    mnx 2013 P85

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    #3 mnx, Oct 5, 2012
    Last edited: Oct 5, 2012
    You should probably post this in the charging section...

    A quick search and I found this:

    Adapter to combine two 30A level2 into one 60A J1772 - faster charging - Page 2

     
  4. NEWDL

    NEWDL R#350 R#1323 Sig23 8136

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    The answer is: Unless TESLA makes a cable to do this and tells you that it is meant for your car I would not plug your car into it.

    There is no telling what system is behind each of those two plugs.

    JB is the only one who would know how to make this work... and he isn't going to tell any of us. ;-)
     
  5. Ceilidh

    Ceilidh Member

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    Sorry, I tried to post it in the charging section so I'm not sure how that got messed up.

    I very much appreciate the reply. Don't know how the searches I did missed that thread. Thank you!
     
  6. Eberhard

    Eberhard #421 Model S #S32

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    #6 Eberhard, Oct 5, 2012
    Last edited: Oct 5, 2012
    if you have the twin charger , then it may be possible, but then the model S needs two charger ports each connecting to a separate charger.
     
  7. pilotSteve

    pilotSteve Member

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    Huh? Its a single charge port, same in any Model-S. The twin chargers are internal to the car and allow the USE of 80A instead of being limited to 40A.

    I too would be concerned with a DIY adapter that was not properly engineered and test. The post mentioned by @mnx actually sounds like it could be workable.....
     
  8. Ceilidh

    Ceilidh Member

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    I agree that the device proposed on that thread sounds much safer... but of course more difficult to build and heavier to carry in your frunk. Could be worth the time though.
     
  9. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    If you insist upon doing it, then the post that mnx references it is the best way to perform the kludge. It mentions and addresses the two major issues with paralleling circuits -- the polarity (so you don't create a low-resistance dead short) and the balance across the circuits, which requires similar resistances in both wire paths. Using a contactor (versus the manual breaker method in the pencil drawing below it) is a smart way to do it, and even better if the contactor can be driven by a smaller set of contactors that ensure voltage across P1-A/P2-B and P1-B/P2-A (where P1 = plug 1, A/B is the hot leg), so it's practically impossible to create a dead short. Then all you have to do is monitor for balance.
     
  10. doug

    doug Administrator / Head Moderator

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    Just to avoid confusion. The forum this thread currently is in is specifically for battery and charging options for the Model S. E.g., "Should I install an HPWC?", "Can I use this to charge my Model S?", "Do I get the twin chargers?", "How much time to charge he 60 kWh battery?", etc. The Charging Standards and Infrastructure forum is more general.
     
  11. jcstp

    jcstp Active Member

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  12. montgom626

    montgom626 Active Member

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  13. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    Likely an OpenEVSE or a Clipper Creek with two 14-50 plugs, and a quick safety/light interlock to ensure that the legs are properly oriented.

    You need to ensure the circuit lengths for both are the same, the legs are proper (so you don't create a dead short), and then you have to signal to the car that 80A is available.
     
  14. dsm363

    dsm363 Roadster + Sig Model S

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    If Clipper Creek sold something like this that was rock solid like their chargers and safe, I'd buy one. Having 80A at every RV park would be amazing. Of course trying to explain to the RV park what you are doing or how much money they want would be a separate issue.
     
  15. mcornwell

    mcornwell Active Member

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    Sounds like it's a device he made himself. At the end of the blog post:

     
  16. mitch672

    mitch672 Active Member

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    We had some discussion about how to do this, it basically involves running the (2) 14-50s into your own home brewed electrical panel, to add up to (2) 40A legs on each of the seperate circuits into a 100A subpanel, then to the EVSE, there are many many issues with the design, ranging from burning down the RV Park to electrocution. You need several safety checks on the way, and lots of hutzpa to actually use the contraption (and it IS the very definition of "Rube Goldberg") It would feed into an OpenEVSE device or a Tesla HPWC, then to the car. It's a lot of iron & cabling to drag around with you as well..
     
  17. bluetinc

    bluetinc Member

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    Hey All,

    I saw this tread and figured I'd toss up some pics before I manage to get a writeup up on the web site. The short version is that it is a custom EVSE that I designed and built. It has a bunch of processing and safety checks that get preformed on the two inputs to see what it can do with the inputs, takes care of communicating with the car etc, and continues safety checks during charging. I've found all of the RV parks to be very happy to let me use two 14-50R's, and all but one have been usable for my system. Here are a few pics of one of the easier hookups with two 14-50R's on the same post :)

    Peter

    74513_10151362885244721_1018146523_n.jpg 538625_10151362885044721_227074973_n.jpg IMG_3450.JPG
     
  18. efusco

    efusco Moderator - Model S & X forums

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    Any chance you'd share the design details?


    Evan, Via Tapatalk
     
  19. unclfuzzy

    unclfuzzy Member

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    Better yet, give us a price on a built one. :)
     
  20. JohnQ

    JohnQ Active Member

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    Please don't give me any incentive to change my config to include twin chargers! :tongue:
     

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