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Tesla, TSLA & the Investment World: the Perpetual Investors' Roundtable

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How does drawing from the battery help? Negative torque (opposing motion) is regen.
Correct, thanks for stating it so succinctly. I think the original poster (I've lost track, too busy doing Mod stuff to go back and find them) thought that driving the motor against the motion, rather than just sucking out energy, might be better. It is possible to do this, but a really bad idea. The truck has energy (kinetic and gravity potential) that needs to be dissipated. If you take more energy out of the battery to drive against the downhill motion, you are simply adding more energy. All that energy has to go somewhere, and that is into the motor as heat. It wouldn't take long to do serious damage when we're talking hundreds of kW.
 
Have we any knowledge - or supposition - of any single or dual motor Tesla vehicle that has had regen disabled because of such failure? If so, what has been the failure rate, either per size of fleet, or per total fleet-miles/km?
I don't have the data but HV contactors have failed and without a connection to the pack I think the inverter would cease to function.
 
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OTOH, if more people posted in there it wouldn't be a graveyard
But people don't use the other threads unless forced to. Many if not most of us use this thread as a catch all... not that there's anything wrong with that IMO. Just pointing it out.

@mongo put up a great post encouraging folks to use the Tesla Semi thread, but hardly anyone followed him, so he's mainly posting here too. That's why I refer to the other threads as the graveyard... posts go there to die.

This thread has the second most posts of any on TMC, so it is by default the catch all thread.
 

Link not loading for me.

But I actually think them doing a FSD discount to say $7000 from $12000 or 1 year free FSD subscription for any deliveries in December would be an insanely smart move. They wouldn't compromise current margins and I think that would drive a ton of demand for Dec. I'm actually not sure why they're not doing that sort of incentive instead of the temporary price cut 🤷‍♂️
I was really confident they would take this approach. Offer FSD at substantial discount, up to the full loss $7500 for December delivery. The only reason it wouldn't be a solid win is because they are adamant about protecting the value of FSD - buyers would have in mind they could get it later at say a 'Black Friday' discount.
FSD is the franchise, it's the razor blades to the razor. Elon has essentially said autonomy is coming inevitably, whether from Tesla or someone else, and if you are not a player then you are dead. And this is the reason I believe they will switch to subscription only, and it is why I have decided to add FSD (at a locked in $12K, fortunately) to my MY when I take my order off hold (expires on 1/1/23) on 12/31 shortly before midnight :cool: .
 
I assume you have much more interesting topics we should be discussing this weekend, please share.

how much fightin' did you have in mind?

"Toothless USA eliminated from World Cup as Netherlands expose talent gap"


(this is only on my mind because my son is over in Amsterdam this past week and was advised to "keep your head down" today by friends} :oops:
 
how much fightin' did you have in mind?

"Toothless USA eliminated from World Cup as Netherlands expose talent gap"


(this is only on my mind because my son is over in Amsterdam this past week and was advised to "keep your head down" today by friends} :oops:
So....nothing, got it. Maybe don't clutter the thread with complaints when there is nothing more important to discuss. Semi is the latest and greatest product from the company in which we are all invested, nothing could be more on topic.
 
I think petit_bateau's point is that reversing the motors to actively brake, instead of regen, would generate significantly more heat (and much more quickly) than anticipated.

So I think we should look at it this way:

How much power (in KW) does it take to go uphill at a constant speed? That should be the same power (in the form of heat) that you'd need to dissipate going downhill. As long as the motors + cooling system can convert that to heat and dissipate it out into the air, then there's plenty of "braking" capacity to go downhill, even without regen.

Edit: Relying on the friction brakes to "travel" downhill is a no-no. That's riding the brakes and is a sure way to deplete your available braking reserves.
regulators and insurance firms will be all over this safety issue. Class 8 trucks brakes are a huge safety issue and constantly inspected by any diligent trucking firm. The entire system of air brakes is actually a very interesting mechanical solution. I will be curious to see how Tesla has implemented their solution. He brought up a very good point.
 
While I'm a big proponent of a catch all thread, it is amazing how the perpetual investors thread seems to have become the Semi thread this weekend...

The curious part is that this forum expert panel seem to think that Tesla's engineering team are idiots that must have ommited several aspects of basic design and the semi is a prototype that simply sucks.
 
Got it, so I missed that the cars price already had EAP in it.... makes sense.
Thanks and I haven't seen any MX deals yet...

Well then that was a dumb post on my part... Will try to delete it 🙂 !!

Edit: The Tmc gods and their delete timer ⏲️ expired.
Great now my stupid post is stuck on the thread.
If you become a supporting member you get a lot more time for edits and deletions, up to a day for the the top group (I think). Just sayin'... worth it IMO