dennis
Model S Plaid
Most of them are not into the fine details. That's why they are journalists and not engineers. :smile:
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Most of them are not into the fine details. That's why they are journalists and not engineers. :smile:
Just to clarify, what added to the confusion wasn't just the media misrepresenting (I'm sure that happened too), it was Tesla offering info of 261 miles for P85 and 285 miles for P85D. Now those are lined up at 285 and some say that is an older change, that just hadn't been communicated. It left an impression that P85D, too, would be an improvement. So far, of course, P85D hardly has been an improvement range-wise.
Vger
Active Member
The thing is, the blog simply re-states, clarifies, illustrates and expands on what they said on October 9 and 10, before people started ordering the car. Half of the heat dissipated on TMC comes from the internal friction between those who listen carefully to what Elon, Jerome and JB actually say, and those that construct an artificial world from bad press quotes, speculation, assumptions, extrapolations, and doubt.
I hope WE have all learned a lesson here.
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I am no electromechanical engineer, but I bet it is damn sophisticated. It is not as simple as turning off the power. I would guess that there is an intricate electronic "balancing act" that goes on at a millisecond or even microsecond time-scale.
Yes, we hope especially Tesla has learned a lesson here.
Tesla didn't clearly tell, before-hand, such a significant portion of range would not be immediately available.Really, telling buyers the range wouldn't be there immediately would have been trivial. They managed to do it for the AutoPilot, it would have been even simpler for the range. Part of me has a nagging feeling they may have hoped it would fly under the radar. Hopefully not.
Krugerrand
Meow
Shutting of one motor and it's power electronics would be my guess (due to the "awkward engine startup" comment)
I'm leaning on unintentional anyway, but it really would have been a very easy thing to communicate. In any case, all this will blow over - the blog was a fine entry, if late, and if the software update follows and delivers somewhere relatively close to as communicated, all good.
Yes, we hope especially Tesla has learned a lesson here.
Really, telling buyers the range wouldn't be there immediately would have been trivial. They managed to do it for the AutoPilot, it would have been even simpler for the range. Part of me has a nagging feeling they may have hoped it would fly under the radar. Hopefully not.
My guess, based on the chatter that some people were hearing from their DSs about trying to push a software update out before the end of the year, is that it's less sinister than that--I suspect that they were working their asses off trying to get the software ready to ship and that they hoped they'd be able to do it before too many cars were delivered, so that it just wouldn't be an issue.
That would explain the somewhat awkward communication roll-out, too; hoping that a tweet from Elon would settle things down and buy enough time, and then realizing that because the s/w wasn't going to be out in a week or so that they had to do something more comprehensive.
The mentioned the motor will still keep spinning. Anyone familiar with AC motors or the Tesla setup, can an AC motor run without torque being applied or can the torque be adjusted from very low to high? Or does that mean it is just rolling from the motion but is actually off? Maybe that could explain how complex on uncomplex the actual mechanical/electric part may be?
I'm guessing the hard part is the software that operates the hardware, so it keeps the experience smooth and safe.
Owner
Active Member
I think this as an "engineering number".. as a best case brand new battery, range charged, perfect 70 degree weather, no traffic, flat highway, no wind and running the battery down to below "0".
I've done a lot of driving in California on busy freeways nearish 65 and have realistically never hit anywhere near 285. I would say a realistic any condition, non-range charge, don't worry take a side jaunt range of 200.
Or am I missing something?
I've done a lot of driving in California on busy freeways nearish 65 and have realistically never hit anywhere near 285. I would say a realistic any condition, non-range charge, don't worry take a side jaunt range of 200.
Or am I missing something?
Vger
Active Member
Yes, we hope especially Tesla has learned a lesson here.
Really, telling buyers the range wouldn't be there immediately would have been trivial. They managed to do it for the AutoPilot, it would have been even simpler for the range. Part of me has a nagging feeling they may have hoped it would fly under the radar. Hopefully not.
Those of us who bought the Signatures know well that this has happened before. The "sleep mode" that significantly reduces vampire losses, was initially released in Dec 2012, just as we got our car. Tesla thought they had solved the problem. Turned out, they had created a rats nest of regression bugs in the process, and had to turn it off for months while they fixed the problems, and then eventually made it much better than it was originally. People here howled the same way about that, and it was truly confusing and disappointing, but Tesla eventually made it right.
I think it is very likely that they thought they had torque sleep working in October or November, and kept hoping it would pop out of engineering before the first cars shipped. Should they have give us a heads-up then? Sure! That is their lesson to learn. But ours to learn is not to immediately assume they are devious money-grubbing bastards seeking to cover up stupid decisions and incompetence with lies and innuendo. No. If you live at the (b)leading edge, 5 years ahead of the competition, this stuff happens. I can deal with that.
A possible scenario, indeed. Very human too, we all probably have been late at some point in life and had some issues with what we are doing and worked to fix the situation in silence and hoped it would all get done soon enough and we'd get to fly under the radar. Only it gets worse if we are late and don't get things done in time, because then we look like doubly in the wrong. In such a case it would have been much better if we would have been upfront before we were busted. No matter how human, it is still a form of hoping to fly under the radar. It may not be fully intentional, but then we still would and should have known we can end up being late, so that part is where the criticism rightly lays.
Krugerrand
Meow
And on the other end of things, knowing that this is how humans operate, we might keep that under consideration when judging the actions of others? And not automatically think they're being evil?
I took that to mean that the stator is still spinning inside the motor, which of course it would be because there's no clutch between the half-shafts and the gearbox or the gearbox and the motor to disengage.
FWIW, I don't think Tesla are devious money-grubbing bastards seeking to cover up stupid decisions and incompetence with lies and innuendo. My opinion is I saw very little unreasonable criticism in this case and even most suggestions of "malice" were on the benign level of giving us some knowing silence or PR spin instead of being as open as they could be.
Don't worrry, Tesla is well loved here, even by those who are not afraid to be critical when they so feel. It is a form of caring about the product and the company as well, tough enough love.
Todd Burch
14-Year Member
Hey, we don't need your Canadian, anti-American comments here. (Just kidding. Sadly you're 100% right.)
Cottonwood
Roadster#433, Model S#S37
Here are a some pretty good sources:
Induction motor - Wikipedia, the free encyclopedia
A nice way to think about how the induction motor gets current into the rotor from the stator without any brushes or connections is that it works like a transformer. If there is no current in the stator, then there is no current in the rotor, and then the inverter can be turned off. At a steady speed, the momentum of the rotor does not matter and the only drag in the motor is from the bearings and the rotor spinning through the air. This is very different from an ICE that has pumping losses.
At a steady highway speed the power demands are a fraction of what is needed for spirited acceleration. If you assume that the inverter/motor pairs are less efficient at low power levels, then you gain some efficiency by shutting down one of the inverter/motor sets and operating the other at a higher, more-efficient power level. The only tricky part about this, is ramping power up and down smoothly. I am sure that these ramp down/up changes in relative power can be done on the 1/10's of second time scale so that the user does not notice any transitions, and the motors are happy.
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Andyw2100
Well-Known Member
I'm not sure what your point is. Sure, it's all going to work out, but why in the world did Tesla not just put this information out before they started delivering cars? I posted the following on the blog entry, immediately after reading it:
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This is excellent information, and very, VERY good news for current and future P85D owners. It is presented quite clearly, and is certainly easy to understand. Thank you.
I would like to add, though, that Tesla could have prevented a lot of worry and concern being felt by new P85D owners over range numbers and energy usage figures that we were seeing that were not in line with our expectations if Tesla had simply made us aware that this January software update was in the works, and that our vehicles were not yet as efficient as they would be. Instead, we were given our key fobs, and our fantastic 0-60, 3.2 second Insane Mode masterpieces of technology, with not so much as a word of warning as to the fact that we should not yet expect to see the range or energy usage that was on the window stickers that came with our cars, or that had been on the Tesla Motors site when we ordered our cars. Frankly, this caused a great deal of anxiety and worry. At a time we all should have been exuberantly enjoying our brand new wonder-cars, many of us were wringing our hands, wondering if they were ever going to achieve the range we expected them to. This just wasn't necessary. I thank you, sincerely, for providing this information now, but can't say strongly enough how much better it would have been if the information had been offered a month ago.
Thanks again for building great cars!
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Tesla told us, at the D announcement, that we would not have most of the autopilot features at the time our cars were delivered. And I don't think you saw anyone here complaining about a lack of autopilot features in their cars. (If you did, there certainly were not very many people complaining about that.) The issue here wasn't so much the lack of range, but rather the lack of communication. My guess is that Tesla didn't communicate this issue at the D announcement the way they did the Autopilot features because they hoped to have the software in the car at the time the cars were delivered. Great. That's admirable. But at some point, someone realized that wasn't going to happen. My concern is for whatever decision process kicked in at that point and resulted in the decision not to immediately put out the information they put out today. Clearly they had it available. This is the issue.
The lesson that should be learned is that the Tesla early adopters are a very understanding group, and will put up with a great deal, but we also want to be leveled with. Provide us with honest information, and we'll be Tesla's best ambassadors. Why wouldn't Tesla want to do that?
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