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Can you schedule the completion of a charge?

Discussion in 'Model S: Battery & Charging' started by cmorgan, Apr 18, 2016.

  1. cmorgan

    cmorgan Member

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    Hi all.

    New member here, great forums with lots of helpful information.

    I've searched around a bit and couldn't find the answer to the question I've posed in the topic. Thought was to be able to use that around range charges.

    Haven't taken delivery yet so it isn't something I could poke around in the iPhone app looking for. It did come to mind that I could use a computer and VisibleTesla to manage this kind of thing but that seemed a bit clunky.

    My 2012 Plug-in-Prius has this feature in its charge controller...
     
  2. tezzla

    tezzla Member

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    Currently not possible, many here are hoping Tesla adds this feature.
     
  3. shokunin

    shokunin P85 & S40

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    You can schedule the start of charge but not work backwards to schedule the "finish by" time. Sometimes the chargers will for whatever (safety) reason (cable temps, resistance, inductance, etc) knockdown the charge rate, with no way to catch up if it lowers the charge rate.

    It would be a nice feature for when I need to range charge and I want it top off to full 15 minutes before I plan to leave.
     
  4. ArtInCT

    ArtInCT Always Learning

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    Everyone has been asking for this feature... and waiting... and waiting .... and waiting for it.
    Also would prefer that the S no begin charging as soon as I plug er in....
     
  5. Lloyd

    Lloyd Active Member

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    Tesla has not offered this feature. However, the Toyota Rav4 EV does have this feature with the Tesla drivetrain. So it is possible when Tesla wants to offer this feature.
     
  6. ArtInCT

    ArtInCT Always Learning

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    #6 ArtInCT, Apr 18, 2016
    Last edited: Apr 18, 2016
    Perhaps one of the knotty problems with the Charge By Time is that the main traction battery's condition is not known in terms of temperature. From what I understand, the battery management system has to get the battery in a suitable temperature range before charging starts or is optimal. There were some threads about delayed charging (or flat out no charging) in both severe cold and very hot conditions (Canada and Arizona... go figure).

    I wonder how Tesla could figure out the pre-conditioning time with accuracy for these outlying situations? For instance, does the S know there is a 40 MPH wind chill factor? Or the tarmac is 100 Degrees and throwing off immense radiant heat?

    I am not making excuses for Tesla but these outlying situations are problematic... however, the Tesla App could always message us that charging is being delayed due to environmental or voltage factors. Those of us in the sweet part of the bell curve do not care about the edges.
     
  7. AEdennis

    AEdennis Active Member

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    Yup... YEARS of requests...

    I have been very lucky with my calculations on this. But my EVSE is Hardwired, 30A inside a garage... I've had issues when using UMC when visiting other locations. There, I just plug in and go, that way I can monitor it while I'm awake.
     
  8. cmorgan

    cmorgan Member

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    Hmm.

    Well I appreciate the feedback here. Maybe it will be implemented in the future!
     
  9. SCW-Greg

    SCW-Greg Active Member

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    It doesn't seem too terribly complicated. Certainly not as complicated as something like autopilot.

    Some assumptions...
    1) Plug car in to power source (with plenty of time in advance)
    2) Via App choose end charge state and time
    3) Car tests connection current, battery state
    4) Car senses temperature and/or pulls weather forecast?
    5) Car calculates optimal time to start, updates app with forecast
    (or if not possible due to inadequate time/charge amps)

    This should provide a pretty reliable forecast.
     
  10. Rocky_H

    Rocky_H Member

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    I'm curious why you would say this. It has always had this feature of scheduled start time.
     
  11. ArtInCT

    ArtInCT Always Learning

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    I am aware of the start time feature. If you turn that off, or do not set the start time, then the S immediately begins a charge if the battery state is less than charge limit. In most cases if not all, the start time feature is appropriate for me and I use it most of the time as my driving habits are just that, pretty consistent.
     
  12. James Anders

    James Anders Member

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    Yeah, if Elon can land a rocket on a barge then back-calculating a charge completion time seems downright trivial.
     
    • Funny x 1
  13. cmorgan

    cmorgan Member

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    Yep, that's kind of how I imagined it could work as well.

    Sounds like something VisibleTesla could initiate, or if we had another open iPhone app for control of the car, or another app like that energi one that will get pulled due to overlap would the Ford car.
     
  14. brkaus

    brkaus Member

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    I'm sure it's the corner cases that's keeping them from implementing.

    What happens when it senses a problem and kicks down? Or it gets colder outside?

    It could text message
    Then car starts charging at calculated time and current limits 10 minutes after started like happens when I use the charger up the street.
     
  15. SCW-Greg

    SCW-Greg Active Member

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    You could have the app perform 2 stage charging, charge the first 90% to bank that, say up to 2 hours before needed. Then based on previous conditions, top off in the final minutes. Of course topping off is always the slowest part of the charging curve, but just saying you pad the last portion of charging with ample time - and based on safely banking from the previous charge and conditions.
     
  16. ArtInCT

    ArtInCT Always Learning

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    I normally charge to 80% now that the weather is getting warmer here in the Northeast. Daytime temps are in the mid 60's to 70's so HVAC use is much less to none. Have my charge set to kick off at 5:30 AM and all systems are GO usually by 7:20 AM. I do not have off-peak electric rates. Typical days' travel is about 44 miles total which is now consuming about 50 rated miles or less. Charge rate is about 27 miles per hour at 40 Amps / 240 Volts. Very happy.
     
  17. Todd Burch

    Todd Burch Electron Pilot

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    As others have said this request has been around since the beginning of the Model S.

    I think they don't implement it because they don't want to be responsible for your car not being charged at the appointed time if the current has been reduced for some reason.

    Which is a stupid reason, so I hope I'm just wrong and they'll implement it soon (though I've been saying that for 3.5 years now...)
     
  18. tinm

    tinm 2013 S85 Owner

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    My kingdom for the ability to tell the car "charge until 7:20am or 90%, whichever comes first".
     
  19. brkaus

    brkaus Member

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    One could always use a JuiceBox Pro as the home charger to add some of the rules.
     
  20. tomp

    tomp Member

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    I'm shocked they haven't add this functionality yet. It can't possibly be that hard.
     

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