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Shake Down Cruise Today

Discussion in 'Model S: Battery & Charging' started by rlawson4, Dec 4, 2012.

  1. rlawson4

    rlawson4 Member

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    So, I did 212 miles today with 8 to spare. I started with a rated range of 241. My question is the rated range change as well as the projected range throughout the day. In the end (as you would expect) they were almost the same. I would have been able to go 220 miles. My question is why did the rated range change? I thought that was ideal range etc. Or, did it change because the rated range was affected by use of the nav system and the 17" screen and A/C or Heat?

    Also a second question, would there have been a reserve. I used about 67 Kwh of the battery. Or, is the reserve switching to range mode at the end in order to catch some of the last 10% of the battery?

    Thanks.
     
  2. Jason S

    Jason S Model S Sig Perf (P85)

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    Rated is basically the EPA range. I get rated range going about 70mph down the freeway without running much else (maybe lights, always stereo), for instance. Nav and screen are just assumed for the rated range, imho.

    A/C and Heat have a little effect, but it isn't much overall when you are zipping down the freeway. Sitting in the driving or traffic and the A/C or heat will have a greater effect per mile cause you ain't moving!

    Few have dared drive below zero, but I recall reports of people getting away with it on Roadsters. There is probably just a little bit left, but I wouldn't count on it.

    Switching to range mode allows charging the full 85Kwh rather than stopping at 90%. Using 67... that sounds wrong. I think you meant 76; that would be close to the standard charge which is 90% of capacity of the 85Kwh battery.
     
  3. apacheguy

    apacheguy Sig 255, VIN 320

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    Well, actually in another thread regarding a potential battery reserve, vbsdan reported reaching 0 miles of range and the dash indicated only 77 kwh had been used. Seemed like this was from a full-range charge. So 67 could be possible if starting with a standard charge. No sure where the missing kws are going.
     
  4. rlawson4

    rlawson4 Member

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    I did a standard charge and thought I saw 67 uses when my day was done. I did 90% highway today and did 212 miles. I drove 60 mph. I liberally used excessories and A/C. Was 212 with 8 to spare a good outcome? Should I have expected closer to a 240 range?
     
  5. Jason S

    Jason S Model S Sig Perf (P85)

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    Trip meter should report amount of energy used since last charge and the average speed. That's a good indicator.

    60mph on the freeway should get better than rated range in my experience. Haven't had a chance to run with the A/C on, however, so maybe that's the difference.

    The missing KwH is a mystery to me.
     
  6. rlawson4

    rlawson4 Member

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    I will check it next time. I do a 200 mile drive every month or so.
     
  7. brianman

    brianman Burrito Founder

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    Clarification: Trip meter reports distance, consumption, and rate of consumption. Not average speed.

    At least in v1.15.14 :(
     
  8. rlawson4

    rlawson4 Member

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    Okay I just checked. I used 65.5 Kwh I drove 211.8 miles. I have a rated and projected 8 miles to go. I averaged 310 wh.

    So, not sure how that compares to others. As a I mentioned, I made to effort to curb the use of the accessories. They were used 6 hours plus today.
     
  9. apacheguy

    apacheguy Sig 255, VIN 320

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    Hmm... Something just isn't adding up here. Even for a standard charge more than 65.5 kw should be available. Is the number reported on the dash accurate?
     
  10. brianman

    brianman Burrito Founder

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    I presume you mean: 310 Wh/mi. Doesn't affect the numbers, but it's always good to get your units right.

    310 Wh/mi. * 211.8 mi. = 65658 Wh = 65.6 kWh

    85 kWh * 90% = 76.5 kWh for standard charge

    65.6 is indeed quite a bit less than 76.5 for a mere "8 mi." projected remaining


    Perhaps he started with only a partial standard charge.
     
  11. Jason S

    Jason S Model S Sig Perf (P85)

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    310wh is about right for the speed and usage. The trip meter adds up. Seems likely that started with 240 projected but not rated? The vampire usage could explain it too, but I think the vampire usage shows up pretty quick after starting out, doesn't it?
     
  12. rlawson4

    rlawson4 Member

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    I think I started full. I have had the car 1.5 days. That being said, I thought the 76.5 KWh was a range charge? Yes it was 310 Wh/mi.
     
  13. dsm363

    dsm363 Roadster + Sig Model S

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    I believe ideal range is based off of 265 Wh/mile if that helps with calculations.
     
  14. zdre

    zdre 40kWh Model S P6415

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    Please correct me if I'm wrong, but I thought that only 80% is actually available in standard charge mode since the battery is charged to 90% and discharged down to 10%. When the projected range is 0, there are still ~8.5kWh of reserve charge left.
     
  15. dsm363

    dsm363 Roadster + Sig Model S

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    Someone correct me if I have these numbers wrong but that is on the Roadster (I'm pretty sure those are the correct numbers for the SOC range). On the Model S you go from 90% to 0% SOC (there still is something left though even when you run out as you have a month to plug back in before trashing the battery pack).
     
  16. brianman

    brianman Burrito Founder

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    Yah, I thought it was [10,90] for the Roadster and [0,90] for the Model S.
     
  17. Zextraterrestrial

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    I think there is maybe a 10Kw safety at the bottom that you could use for the '2 months' unplugged at 5% charge before the battery is really hurt
    Safety factors are kind of important in engineering. Over do it if you can for safety if the cost is reasonable.

    I used most of a range charge and had quite a few kWhrs left based on the used power - I think it is a good thing
     
  18. Brian H

    Brian H Banned

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    Someone on TM forum (Teotawaki, IIRC) managed 4-5 mi limping home after 0 range left. So there's a bit down there!
     

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