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darth_vad3r
Well-Known Sith
I presume that's 4.5 "mi/hr" charging speed? If I had to guess, the charging speed is calculated from the charging power (P) and some consumption/efficiency factor (F). So while it's not averaged it's still calculated, but ya, that seems likely a bug in one area displaying it truncated or rounded via 'floor' instead of rounding to nearest.
I could dream up an explanation that's technically not a bug, but a discrepancy ... say two different consumption factors were used to display it in the two different locations. OK, that stilll sounds bug-esque, but it's a possible way to show different numbers without actually blaming different rounding methods, e.g.
P = V * A (say 110V * 12A = 1.32 kW)
F = either a rated or calculated/estimated 'current' consumption, like say 300 Wh/mi or 290 Wh/mi
S1 = P / F2 = 1.32 kW / 300 Wh/mi = 4.4 mi/hr
S1 = P / F2 = 1.32 kW / 290 Wh/mi = 4.55 mi/hr
F = either a rated or calculated/estimated 'current' consumption, like say 300 Wh/mi or 290 Wh/mi
S1 = P / F2 = 1.32 kW / 300 Wh/mi = 4.4 mi/hr
S1 = P / F2 = 1.32 kW / 290 Wh/mi = 4.55 mi/hr
So if the app is reporting a number using one factor, and the in-car display using another factor you could see "4" in one spot and "5" in the other.
This was intriguing me so I went back through my data points on range in mileage. For a bunch of the datapoints I took snapshots in both km *and* mi (in addition to almost always taking the snapshot of %). I haven't figured out how to make any determination on % rounding yet since my car's not mapping rated miles to % any more (it did exactly for the first while (weeks?), but for the km and mi I can convert between the two and compare expected values.
e.g.
Car displays 240km or 149mi of range remaining.
a) 240km = 149.129mi, rounds to 149. Checks out.
b) 149mi = 239.792km, rounds to 240. Checks out.
... repeat for tons of data points ...
a) 240km = 149.129mi, rounds to 149. Checks out.
b) 149mi = 239.792km, rounds to 240. Checks out.
... repeat for tons of data points ...
Or, I guess just cherry pick and look for ones where rounding method would be obvious. 1 actual mi driven should display as 1.6km which is either going to be "1" or "2" depending on rounding method. ... will have to think about this and see if I can determine anything definitively or not from my data
darth_vad3r
Well-Known Sith
I re-read this and the data you posted. I disagree. DC Wh/mi is calculated, not measured.
a. 495.11 miles is measured.
b. 222.81 amp-hours is measured.
c. 351 average voltage is ... averaged? From ... multiple measurements? Or guessed?
222.81 A-h x 351 V = 78,206 calculated Watt-hours
78,206 Wh / 495.11 = 157.96 Wh/mi
My question in this is how do they arrive at 351V average? If their average method is inaccurate the energy calculation is as well.
The miles has 2 sig figs (495.11).
The amp-hours has 2 sig figs (222.81).
Why is the voltage zero sig figs (351)?
darth_vad3r
Well-Known Sith
The Tesla EPA submission document also references being in "dyno mode" to prevent faults from traction control.
I wonder if "dyno mode" does anything else ... like let more of the battery be used before shutting down?
I wonder if "dyno mode" does anything else ... like let more of the battery be used before shutting down?
Blu Zap
Grinning member
Great conversation here. Perhaps you can help me solve a question, especially in light of the recent 2019 16.2 update. 2014 P85+ "D" battery. Just drove 182.2 miles. Started with a 100% charge (227 miles rated) Ended with 7% (about 15 miles rated) My question is about the 58.1 kWh consumed. Okay, if the 85 is really 77 kWh, what happened to the rest? The drive was at 319 wh/mi. So not too far out of line. But say this drive used 60.0 kWh total, where did the rest go? I am missing 17 kWh. Has the battery degraded 22%? Before the software update, the rated range was ~255 miles vs. original 265 miles.
I appreciate any insight. Thanks,
I appreciate any insight. Thanks,
Need the canbus data, but IAM suspect you can find a lot of that percent in the 4kw buffer used to calculate 100%. Also 319 wpm is above EPA rated consumption so you have a small multiplier there to reduce the dash display miles remaining.
Good info, @supratachophobia, and it would help to know how many miles are on the car, @Blu Zap, as it WILL degrade with mileage. There are a few graphs and charts available but it would be helpful to know your Odometer reading.
Given the thread:
Sudden Loss Of Range With 2019.16.x Software
It's time to change title of this thread
Sudden Loss Of Range With 2019.16.x Software
It's time to change title of this thread
Blu Zap
Grinning member
Hi, I have 67,000 miles now. I just put 2,100 miles on it the last 10 days. So several sections of 180 mile or so. I don't use rated miles when I drive long distances. It is all bogus. I use percentage of battery and wh/mi. That is what I measure to see if I am on track. That way effects like headwind, cold weather, etc. can all be observed. Yes 319 wh/mi. is higher than the 295 wh/mi. the EPA used to determine rated miles. But either way, in the life of this car, I always keep it between 20% - 90%. My rated miles before the software change was 255. After the software it is now 227 miles. One can say, they just changed the rated miles formula. But that doesn't explain that after the 182 mile trip from full 100% charge, I had used only 58.1 kWh. 7% remained in the battery after 182 miles. I get it that the battery has been degrading. The 85 kWh battery starts with 77 kWh actual available capacity. But a drop from 77 kWh to ~58.1 kWh? Really? I believe this represents the battery capacity limit of the new software. My 85 can barely go 200 real miles.
Jkr85
Active Member
That is awful.
5 Miles degradation to go and you should get a warranty replacement in any case!
Jkr85
Active Member
Oh oops, you’re right... I remembered (wrongly) that the guarantee in my docs at delivery did mention a threshold of 70%... no idea where that came from, because it indeed states ‘loss of Battery energy or power over time ... is NOT covered.’
Please ignore my previous post.
The Model 3 battery warranty guarantees 70% capacity, but it is limited to 100k/120k miles...
Technically I believe the statement read 'excludes normal battery degradation'.
Jkr85
Active Member
Not so, interesting read on the 2013 forum:
Battery warranty Model S | Tesla
And as quoted on teslarati:
What Does the Tesla Model S Battery Warranty Cover?
My quote is straight out of their warranty battery warranty statement from 2015. Google it. It's quoted many times.
I did not know, though, that they ever claimed they'd replace the battery if it got below 70%.
My warranty from 2013 states that the warranty does not cover battery degradation "due to use". That would seem to indicate that artificial degradation caused by Tesla's software, as has been the case for some under 2019.16.2, is covered under the warranty because that type of degradation is not "due to use".
If it's "normal" then it shouldn't need protecting via a recent software update, it would have been known to Tesla for the last 6 years. If you decide to suddenly "protect" something 6 years after you made it, I suspect it's because you found something wrong with it.
Blu Zap
Grinning member
I think we are on to something here. it is not a warranty issue. It is a software issue that reduced the range of the vehicles significantly ~15% overnight. That's not "natural" It is the 8 year "unlimited mile" warranty they are concerned about. If they didn't put these range limits on the batteries, something could happen where they would have to do a warranty replacement. That is the mystery issue they are addressing by reducing our range.
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