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Model S/X dual connectors for dual chargers?

Discussion in 'Model S: Battery & Charging' started by RDoc, Sep 1, 2012.

  1. RDoc

    RDoc S85D

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    My understanding is that with the model S and X, the dual charger option means you can charge at 2x10 amps at 240V for 40 amps @ 240 V, but there's only one connector on the car. Wouldn't it be useful in many cases to have two connectors on the car? Some cases I can imagine where this would be useful are plugging into two street charging poles when no one is at two adjacent spaces, or plugging into two 240V wall plugs, or 2 120V plugs, or even one 240V 240V and one 120 V plug simultaneously.

    It would seem to me that having the option of choosing either two independent supplies via two independent plugs, or ganging both together to get a higher current through one would be a major advantage. The cost would just be the extra car plug and a relay in the car I'd think. Driving an EV in the wild is still a bit of an adventure, so the more options the better I'd think.
     
  2. markwj

    markwj Moderator, Asia Pacific

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    See: Charging Model S | Tesla Motors

    Each charger is 10kW (W=VA, so a single charger is around 40Amp @240V).

    Dual chargers allow for charging up to around 80Amp @240V.

    Lots of discussions on these forums about charging from multiple outlets simultaneously. Opinion seem to be that it is tricky, and nearby outlet are likely to be on the same breaker anyway.
     
  3. TEG

    TEG TMC Moderator

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    #3 TEG, Sep 2, 2012
    Last edited: Sep 4, 2012
    Related / previous mentions of that idea:



    The idea of having the dual chargers be able to run separately makes even more sense when you consider that there is opportunity for a symmetrical charge flap on the other side of the car that could support another J1772 socket. Plus you have rows of public J1772 charging stations that are typically just 30amps each, so connecting to only one at a time would use only a small fraction of the Model S charger's capability.
     
  4. spleen

    spleen Active Member

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    I would worry though about the appearance of Model Ss "hogging" all the chargers.
     
  5. jkirkebo

    jkirkebo Model S P85+ VIN 14420 EU

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    This would be VERY useful for me as all our public charge points are 230V 16A only (except the fast chargers). EU models should support three-phase charging, so the plug must have more pins in it. Having the possibility of purchasing a "breakout"-adapter so each charger can be fed from a completely different supply would be a major plus for me. No need for a separate charge port, though obviously that would work too.
     
  6. NigelM

    NigelM Recovering Member

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    But half the charge time. (assuming its technically feasible)
     
  7. 100thMonkey

    100thMonkey Member

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    I think a symmetrical charge port on the opposite side of the car as an option would be brilliant. This would make combining sources possible without going around safety protocols.
     
  8. Robert.Boston

    Robert.Boston Model S VIN P01536

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    And it would make charging while parallel parked simpler, using the passenger-side port alone.
     
  9. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    +1. I am not looking forward to having to run the cord around to the wrong side of the car, which is what I will have to do when I'm parked at home.
     
  10. RDoc

    RDoc S85D

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    Ah, yes, I just mistyped/misthought that.

    Charging from 2 outlets via some kind of Y connector is not only tricky, it's dangerous. Using two chargers though isn't so bad. If the outlets are on the same circuit, it will pop the breaker, but it doesn't take much checking to find ones on separate circuits. As long as the chargers are electrically isolated from each other, yet communicate to keep the charging even, it shouldn't be too impractical I wouldn't think. Dual chargers likely have some coordination in any event.
     
  11. spleen

    spleen Active Member

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    Only if you were charging to full. I assume most of the time where you'd run into a situation where you'd be using two chargers would be in public during opportunity charging. In other words, the amount of time that you're charging for would be fixed (the amount of time that you'd be eating at the restaurant, watching the movie, shopping, etc. etc.). It's just that now you're using up double the infrastructure. For other situations such as overnight charging while stopped at a hotel during a road trip, a single EVSE at 30-40 amps would most likely be sufficient to top you off.

    While faster charging using dual chargers obviously would benefit us (Tesla owners), it doesn't help encourage adoption of the technology for others who would find more chargers being used up. This could be mitigated somewhat through the usage of charging etiquette signs/placards but does somewhat feel like we'd be taking more than our fair share of the public EV infrastructure ("those Tesla hogs - they're always using up two chargers!").

    OTOH, I do see the benefit of having a second charge port on the other side - as others have mentioned, sometimes stretching the cord around can be tough ...
     
  12. RDoc

    RDoc S85D

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    Whenever I've seen pictures of cars at public charging stations plugged in, they've been alone. Perhaps in the future that won't be so much the case as more cars come in simultaneously for charging, but I'd not be surprised if signs inviting unplugging didn't become part of EV culture.

    Another use for dual outlets is charging at a friend's house. There are a lot more people with multiple accessible 110V outlets than single 220V ones. A single 110 V charger takes a very long time.
     
  13. ChadS

    ChadS Petroleum is for sissies

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    #13 ChadS, Sep 9, 2012
    Last edited: Sep 9, 2012
    There's plenty of times in the Seattle area that all EVSEs in a location are in use, so we are working hard to get charging cards adopted as part of the culture. There's a very simple one (it just says you can or can't unplug; nothing about unplugging after a certain amount of time) HERE.

    I also ran in to another Roadster at a charger in Orland, CA once and had to wait for him to finish. (Fortunately he was by the car, so I didn't have to wonder if I could unplug him or not).
     
  14. RDoc

    RDoc S85D

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    That's interesting about Seattle and the cards. That sounds like a really good idea.
    With Teslas I'd think they'd hardly ever get to a full charge on a public station, except perhaps overnight at a hotel or something similar, so saying when it could be unplugged probably wouldn't be used much anyway.
     
  15. ChadS

    ChadS Petroleum is for sissies

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    #15 ChadS, Sep 9, 2012
    Last edited: Sep 9, 2012
    I think the sign is always a good idea. Even overnight (and regardless of car type), one might be full by, say, midnight--and a late arriver might appreciate the chance to plug in then. Plus, one doesn't necessarily need to get a full charge--you just need enough to get to the next charger. If you're all day at a conference or something (and can't come back out to move your car), it's nice to let people know when they can unplug you. If the time is close to when they arrive, they may choose to just wait. I'm thinking of getting a clock like this:

    will-return-clock.jpg

    When there is no sign, I think the general protocol is that whoever gets there first gets the station until they come back and unplug--which really stinks if you are the newcomer and you have no way of knowing how long your wait will be, or if the car sitting there really needs the charge or not.

    If there was an adapter so a Tesla could plug in to two stations, then I think the protocol would be that anybody that needs a charge could disconnect one of them.
     
  16. gg_got_a_tesla

    gg_got_a_tesla Model S: VIN P65513, Model 3 Res Holder

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    Such a card can also refer to a Model S charge port color legend? So, "Feel free to unplug when color's so-and-so" and such?!
     
  17. VolkerP

    VolkerP EU Model S P-37

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    Model S could display a planned charge stop time on its touchscreen that is visible from the outside.

    charging to ... % SOC
    [######_________]
    complete at 02:04AM
    OK to unplug thereafter
     
  18. TEG

    TEG TMC Moderator

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    Yeah, totally. LEAF has 3 blinking lights on the dash... one flashing means 0-33%, 1 solid + 1 flashing means 33-66% full, and last one flashes during 66-99% before they all go solid to say that charging is done. People may not automatically know how to interpret those, and besides the granularity is not good. Having a little readout with easy to interpret, accurate info would go a long way to make plug sharing work better.
     
  19. KenEE

    KenEE P1937 Reward Excellence!

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    seems the better solution would be for the charging station to have a readout. Not sure if all/any protocols have the SOC sent to or available to the station, but that would be more uniform. Everything else mentioned here seems nerd/enthustiast centric.

    Much better to just glance at the EVSE display and see the charge is X%. (and or X kWh delivered over Y minutes/hrs.)
     
  20. VolkerP

    VolkerP EU Model S P-37

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    Tom & Cathy Saxton found out that the SOC displayed by CHAdeMO stations is way off. Read here:
    Quick Chargers: Ignore The Charge Percent! - Tom Saxton's Blog
    So even in advanced DC QC stations that have a complicated protocol, lots of control electronics, and a display, they get it wrong.
    And what about sharing a NEMA 14-50?
     

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