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Power drain while idle (Vampire Load)

Discussion in 'Model S: Battery & Charging' started by dennis, Nov 10, 2012.

  1. Babylonfive

    Babylonfive Power12

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    Unbelievable, and unconscionable. <snicker>
     
  2. dennis

    dennis P85D

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    I have seen 20 miles lost in 48 hours. So I thought it was linear. Although I did notice that the Miles Remaining dropped off more slowly when initially driving after two days.

    IMO though, whether it is 5 miles or 10 miles per day, Tesla should do everything they can to maximize range and minimize vampire loads when the car is not moving.
     
  3. ChadS

    ChadS Petroleum is for sissies

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    #23 ChadS, Nov 12, 2012
    Last edited: Nov 13, 2012
    And I lost 26 miles in 44 hours. That was starting from just about half full. I didn't check it periodically to see if the loss was linear; but it's clearly a lot. (Temps varied from 45 to 65 degrees while the car was sitting; more hours at the lower end).
     
  4. Chris

    Chris Member

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    This is the response from TM Ownership Experience to my inquiry regarding the idle power drain:

    This will be adjustable by a setting. At the moment the processors that run the instrument cluster and touchscreen do not turn off. This allows for immediate responsiveness when you come back to the vehicle – everything is awake as soon as you open the door. The downside to this is that Model S can lose several miles per day when sitting idle. Miles lost per day is much higher when the battery is full and tapers down as the battery gets lower.

    The next software update will introduce a setting that allows more control of the power management of Model S. You will be able to tell the computer to turn off all the background electronics which will get energy consumption when not in use down to near-zero.


    I consider that good news. TM must be very much aware of this issue if they are already working on a firmware fix. I hope that when one chooses to turn off all the background stuff the car is still going to be drivable the moment you sit down in the driver's seat.

    Not sure why the state of battery charge would influence the amount of background drainage though. Must be the battery chemistry rather than CPU load.
     
  5. Leafster

    Leafster Member

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    I guess you all could measure this loss quite easy with the use of a cheap kwh-meter when charging. As soon the battery is fully charged it should draw the necessary watts from the grid.
     
  6. Trnsl8r

    Trnsl8r Blue 85kwh since 12/8/12

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    Am I crazy or wouldn't it be better to...
    - Have it on quick-response mode when plugged in.
    - Have it on quick-response mode for ~30 min after driving or after being plugged in.
    - Go into some low-power, slow-response mode after that.

    That way it's quick to respond when you're in and out while doing errands or jump into the car to drive after charging, but doesn't bleed the battery long-term, no-charge parking.
     
  7. dsm363

    dsm363 Roadster + Sig Model S

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    Great idea. That's what I want too. Quick response for a user adjustable time (30,60 or 90min).
     
  8. jerry33

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

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    It would also be a good idea to have a wakeup time (that it would learn by location). For example when you go to work you would set it for eight hours and then it would come on a couple minutes before and stay on for some selectable time. It would be by location so once you parked at work it would just automatically do that whenever you parked there.
     
  9. weccman

    weccman Member

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    One more data point on this topic: Our Model S went from 263 miles to 247 in about 32 hours in Yosemite Valley with temperatures between 28 and 60. I had heard that in colder conditions, it might use less because of less need to keep the batteries cool, but these numbers suggest that is not the case. I look forward to the firmware update.
     
  10. jerry33

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

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    It might, but colder air is denser which will tend to reduce the range.
     
  11. cinergi

    cinergi Active Member

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    So, to be clear, the range-drop is absolutely real. I see about 6 rated miles per day loss (tested over the course of 5 days). And that's while plugged in -- so it's not waking up and topping off or drawing from AC, either. Tesla also confirms it's currently expected behavior. We're all working with the Tesla ownership team and, like you're seeing with respect to the upcoming software update, this stuff will get addressed.
     
  12. brianman

    brianman Burrito Founder

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    Please forward this on to one of your Tesla contacts as a suggestion. Add dsm363 and brianman as "in agreement" when you send the mail. ;)
     
  13. Jason S

    Jason S Model S Sig Perf (P85)

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    Good one!
     
  14. neroden

    neroden Happy Model S Owner

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    Well, I'm yet again glad I postponed my order. This *has* to be fixed or it's a deal breaker. :scared: Hopefully it'll be fixed by next June. I suggest that the Vampire Load thread be pinned.
     
  15. Trnsl8r

    Trnsl8r Blue 85kwh since 12/8/12

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    Did so, sent it to ownership with a link.

    - - - Updated - - -

    Well, it also uses battery power to keep the battery pack warm enough, so you'll see increased power draw in extreme temperatures on both ends.
     
  16. Vger

    Vger Active Member

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    Roadster owners went through the same evolution. The Roadster was originally very conservative in keeping the battery climate control stuff running when plugged in, and consequently running the battery down, or drawing more power from the grid. Now, it does eventually put the coolant pump and fans to sleep when temperatures allow, and the car is idle for some time. The coolant pump re-starts as soon as you open the door.

    This is a slightly different problem, but my point is that Tesla has a history of not always optimizing this stuff out the door, but then quickly working to resolve issues with firmware updates. New owners and reservation holders can feel anxious, but even when Tesla was a much smaller company, they kept at optimizations like this. Even Roadster 2.0 owners, such as myself, saw maybe a half dozen firmware updates in the first six months or so.
     
  17. mnx

    mnx 2013 P85

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    Spends almost 6 figures on a car and is worried about 20$ a month electricity = priceless. :)

    I'd like it to be fixed too of course, but they said they're already looking after it.
     
  18. Babylonfive

    Babylonfive Power12

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    #38 Babylonfive, Nov 14, 2012
    Last edited: Nov 14, 2012
    OK, I see what you are doing there... but, his point was not the money, but the idea of losing a lot of miles each day that it sits idle. An earlier explanation was around leaving a car at the airport expeting to have the miles available when you get back in three weeks, but then finding too much leaked away.
     
  19. strider

    strider Active Member

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    Why don't they just have the car completely shut down when locked and then boot when you unlock the car? Based on the Roadster boot-up time, there is plenty of time from unlocking the door to driving for everything to wake up.
     
  20. MikeK

    MikeK R#129, TSLA shareholder

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    It has to be at least a little bit awake to actually listen for the key fob.

    I am continuing to hold out hope that Tesla will deliver on their original promise to have the door handles extend automatically when you approach the car (assuming you have the Tech package). This is analogous to how the Prius works -- it will turn on the interior lights when you approach. That runs off of the 12V accessory battery alone, and it is clever enough to wake up and look for the fob less frequently as time goes on, so it doesn't drain the 12V.

    If Tesla were to do this, then they could begin to wake the rest of the computers up once the fob is sensed, or (as others have suggested) as soon as you pull the handle. To do this, though, they might have had to plan ahead to include a low-power system just to sense and respond to the fob, that doesn't rely upon having the main computers all booted up. Many consumer electronic products do exactly this -- they have a dedicated low-power part to handle signals from the remote control, which can then wake up the more power hungry pieces.
     

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