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Pack Performance and Launch Mode Limits

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Actually, you've missed a few points. One is that V = IR. P = IV. Therefore, P = I^2 R. So running at 1600A = 52% more heating than at 1300A. So yes, electrical systems are so precise. I know mechanical engineers have way larger tolerances to work with, mainly because they have to BS their load cases.

I think it's obvious that Tesla had this fully dialed-in at 1300A, downgraded some parts to be cost-efficient at that level, and then forgot about all the little pieces when they tried to increase power.

Yes.. thanks for the grade 11 science lesson. However, if you read what I wrote I said MECHANICAL systems. I'm well aware that electrical systems can be designed a fair bit tighter, because they're largely solid state.
 
Duty cycle was not decreased. Duty cycle is the wrong word.

Peak current was decreased in response to components that should effectively have an infinite cycle life having a very very finite one. In general if you have passive components that fail under cycling you've made an engineering error. Ever hear of the wires in someone's house just "wearing out" and requiring replacement? No, they are passive components, they should outlive the house they are in.

If your M3 revs to 8000 RPM, and then BMW discovers that because of an under-engineered component these engines eventually blow up, then they push a software update to limit to 7000 RPM to prevent that, they have not modified the "duty cycle", they've altogether limited output. Of course the latter part did not happen, but they did blow up hundreds of customer's engines, through no fault of the customers.
People dismissed the motors as part of the problem (so far we do not know yet for sure), but AC motors certainly have a duty cycle and peak power certainly is not rated at continuous. That means there is definitely a wear rating (it's not the copper, but the winding insulation certainly does). I'm wasn't able to find it, but I remember discussion back in the Roadster days about how motors can tolerate running certain temperatures, but it proportionally reduces life.

Insulation in house electrical wire similarly does wear out. The only difference is there is no vibration to give it that last straw and break it apart (while in a car there is). If however you have come into contact with it, it isn't too uncommon to find wiring with insulation that will just crumble at the slightest touch.

IGBTs (in the power electronics) and solder joints (plenty these in the battery pack) also are designed for a certain amount of cycles under certain temperature conditions. There's a lot of continuous leeway that engineering has to decide how to push.

I don't agree with your characterization that there is an "infinite" point and anything that doesn't hit that "infinite" point is an engineering failure.
 
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People dismissed the motors as part of the problem (so far we do not know yet for sure), but AC motors certainly have a duty cycle and peak power certainly is not rated at continuous. That means there is definitely a wear rating (it's not the copper, but the winding insulation certainly does). I'm wasn't able to find it, but I remember discussion back in the Roadster days about how motors can tolerate running certain temperatures, but it proportionally reduces life.

Insulation in house electrical wire similarly does wear out. The only difference is there is no vibration to give it that last straw and break it apart (while in a car there is). If however you have come into contact with it, it isn't too uncommon to find wiring with insulation that will just crumble at the slightest touch.

IGBTs (in the power electronics) and solder joints (plenty these in the battery pack) also are designed for a certain amount of cycles under certain temperature conditions. There's a lot of continuous leeway that engineering has to decide how to push.

I don't agree with your characterization that there is an "infinite" point and anything that doesn't hit that "infinite" point is an engineering failure.

This is all very, very confused. It's about 2 degrees away from just being word soup. Sorry, no other way to break it to you.
 
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Wow....
I was not talking about power numbers or related data. I believe Tesla's heuristics are designed to tell them where the battery system is in its lifespan. They do not need anything from me on that subject.

I was more interested about having the "what do we do now?" conversation. Hey owners, the 100DL battery fixes what we know about but we do not know what we do not know so we can not guarantee the P100 battery will not have another issue (the the web site disclaimer which could only apply to the P100D(L)). Do you V3 folks want one for $20K and 85DL for $30K? Cost sensitivity. Reaction to potential hard failures. Tesla will ultimately interact with us in the future at some point when things fail (at least some, we really do not know how many and when because we do not know the end game failures that drove the need for counter limits) so why not talk with us now as a group and gage our willingness to go along with different options (like the battery buy suggested earlier). That is what I meant by being part of the solution.
Would you be satisfied with a warranty fix to the problem (whatever that may be)? Based on Jon's response I think that's where they are going.
 
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People dismissed the motors as part of the problem (so far we do not know yet for sure), but AC motors certainly have a duty cycle and peak power certainly is not rated at continuous. That means there is definitely a wear rating (it's not the copper, but the winding insulation certainly does). I'm wasn't able to find it, but I remember discussion back in the Roadster days about how motors can tolerate running certain temperatures, but it proportionally reduces life.

Insulation in house electrical wire similarly does wear out. The only difference is there is no vibration to give it that last straw and break it apart (while in a car there is). If however you have come into contact with it, it isn't too uncommon to find wiring with insulation that will just crumble at the slightest touch.

IGBTs (in the power electronics) and solder joints (plenty these in the battery pack) also are designed for a certain amount of cycles under certain temperature conditions. There's a lot of continuous leeway that engineering has to decide how to push.

I don't agree with your characterization that there is an "infinite" point and anything that doesn't hit that "infinite" point is an engineering failure.
There is not an infinite point, but there is a point where years and years of thrashing are not going to have a deleterious effect. Or 6 months for that matter! Please also keep in mind that this is not a temperature issue - limiters are present to manage that already.
 
People dismissed the motors as part of the problem (so far we do not know yet for sure), but AC motors certainly have a duty cycle and peak power certainly is not rated at continuous. That means there is definitely a wear rating (it's not the copper, but the winding insulation certainly does). I'm wasn't able to find it, but I remember discussion back in the Roadster days about how motors can tolerate running certain temperatures, but it proportionally reduces life.

Insulation in house electrical wire similarly does wear out. The only difference is there is no vibration to give it that last straw and break it apart (while in a car there is). If however you have come into contact with it, it isn't too uncommon to find wiring with insulation that will just crumble at the slightest touch.

IGBTs (in the power electronics) and solder joints (plenty these in the battery pack) also are designed for a certain amount of cycles under certain temperature conditions. There's a lot of continuous leeway that engineering has to decide how to push.

I don't agree with your characterization that there is an "infinite" point and anything that doesn't hit that "infinite" point is an engineering failure.

I am not sure motors have entirely been dismissed. Earlier in the thread there was a Tesla tech claiming this issue was about both battery and drivetrain for pre-P100DL. And for P100DL it was only about the drivetrain. It could be wrong info, but just reporting what was said...

Seeking information on what the issues are could shed light on this as well...
 
Would you be satisfied with a warranty fix to the problem (whatever that may be)? Based on Jon's response I think that's where they are going.

Answering for myself, I will be more than satisfied with warranty fixes as a solution. Judging by the overall reaction, I assume most agree. So that is not really at issue here anymore, I think. Tesla made it right and that's unconditionally good.

What I think people are debating is how to best move forwards in other aspects of this. For example, does Tesla need the owner's help in gathering data (I am not sure they do, but some seem to think so) and how to develop further information on this for the community (something I find important)...

Personally, I think we should try to find out all there is to know about this, even if there is a warranty fix. Understanding the weakness and the engineering story behind it is one of those things that car owner communities have been historically valuable in.

At the very latest this information will become valuable once cars age beyond their warranties, but for informational and usability reasons (what to take into consideration) knowing it earlier can also be useful.
 
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Would you be satisfied with a warranty fix to the problem (whatever that may be)? Based on Jon's response I think that's where they are going.

My counter limits are/will be removed so I'm happy. If I can help Tesla keep costs down and reputation up by contributing to and cooperating with a solution, I would be happier.
 
So I gather the architecture of the P100D battery is different, more robust and will handle the extra abuse that enabling Ludicrous dishes out. Have the motors or other components of the drive train been altered/strengthened as well? Any one have some info on that?

I don't think we have much info beyond this...

I found some useful information today. I stopped at a local service center and asked "How many more launch modes do I have in my P85DL before you reduce the power?" I was escorted to the service manager who initially said 625 runs(but could not substatinate it) were needed before power reduction. Then he looked into the computer using my vin to find out. There was apparently a lot of vins listed randomnly but he concluded that my information was not available to him.

He did inform me that there are 2 separate counters, 1 for launch mode and the other for full pedal. He did not know how long the full pedal had to be pushed or if the 2 counters were additive. As far as the P100D the battery is ok but drive train can still be damaged resulting in power cutbacks. Other P models can suffer battery and drive train damage. Then he proceded to read from the official line in the computer which basically said that drive train damage is to be expected from abuse and is common with other manufacturers. It was obvious that Tesla is now aware of the turmoil and has published guidelines for service.

The above helps explain Teslas response to Tech_Guy that a P100D is the answer but left out the part that the drive train could still suffer damage even if using full pedal only.

Service advisor just gave me credible info.

3 counters

One for Launches/WOT over 1500 amps. (I have 92 and have never used launch mode)

One for rolling mashes that are hard but under 1500 amps (mine is 134)

One for "mixture" (mine is 311.6)

They are protecting wire bonds.

625 is hard cut for Launches.

Rolling mashes counts towards mixture. Cut is 3068 for Mixture limit.

Can one of you who has been severely power-cut send me your VIN number through PM? The service manager that I'm working with would like to see your stats to understand if there is any remedy planned.
 
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There is not an infinite point, but there is a point where years and years of thrashing are not going to have a deleterious effect. Or 6 months for that matter!
My point is there is an amount of years and an assumed amount of cycles that engineering decides is acceptable. And this limit may be quite continuous. Just because the limiter set has the cut relatively soon, we can't assume that is the point that the engineers decided. It could be that they are conservative.

Please also keep in mind that this is not a temperature issue - limiters are present to manage that already.
I would not assume just because there are thermal limiters that there won't be a temperature issue. Most limiters are built with some room and go over a little even though that reduces rated life. The assumption is that you rarely hit the limiter, but it's possible to do so frequently if you are constantly doing spirited driving.

The max battery mode also overrides whatever baseline temperature limits Tesla had set for the packs in general. The Roadster had a similar mode, and it was made explicitly clear that it's bad for the battery cells (I believe a similar warning is present in the S/X).
 
@TechGuy refuses to share how many launch mode events he did so the only data point we really have is hostman's ~1k LM events as meeting a trigger.

The rest of us are probably nowhere near that, and probably never will be -- even over 8 years. Especially since LM provides no benefit.

We otherwise have zero info on whether there are any other triggers that some Tesla engineer thought that continued use might result in a failure event.

And lots of data points of innumerable people who have not noticed a power reduction with whatever level of enthusiasum they drive their cars. So it could be that the triggers were only for the most extreme outliers. So even without the triggers, it is only the most extreme outliers who have anything to worry about.
 
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The point is that under severe duty, if the failure mode is catastrophic, the longevity must be great. That's all I'm saying.

Using the unquantifiable term "severe duty" misses the distinction that triggers (and the underlying concern about failures) could have only ever effected people in the 99.99% of driver floggers. And most people wld never have come close.
 
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It's ok bhzmark. There is no problem and no one would ever have been affected by the limits and, if they were, the reduction really would not have been a big deal.

Happy?
Can you leave it alone?
Tesla removed the counter limits so I give up, you win.......
How can people smart enough to buy Tesla be so given to emotion and irrationality and resist getting facts and evidence?