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When Volts go up, Amps go down to get the same Watts out.
Speaking as a local EE, the trick is that when one is moving energy from point A to B on wires, unless the wire is a superconductor, there’s energy lost in the wire.

Assuming that the load resistance of the vehicle is much greater than the wire resistance (usually a pretty good bet), then the power dissipated in the cable is I*I*R, where I is the current and R is the resistance of the cable.

Let’s say we have a MW charger at 1000VDC. That implies the current would be 1000A. That’s a lot of amps. Suppose the charging cable has a resistance of .1 Ohm. Then the power dissipation in that cable would be 1000*1000*.1, or 100kW.

Water cooling or not, that’s a lot of power being dissipated in that wire, so the actual resistance is probably 50 milliOhms or less, but it’s still a lot of heat to get rid of.

Note that going to a lesser voltage, say, 500V, would double the current but quadruple the power dissipation.

So, my thought is that Tesla was forced to use the the 1000V bus to make it all realizable.

Note: all of the above is directly why high tension wires at 10 kV and up litter the landscape. It keeps power distribution efficient.
 

Paul_SF

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Feb 12, 2020
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OT:

6BC83CE5-9667-4A77-92F7-DD3D3FD667C4.jpeg

Hope you got yours! 😁
 
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SmokyPeat

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Oct 27, 2021
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In general you don't handle it while it is charging. And there are lots of checks to make sure everything is fine. Like you can't disconnect it while it is charging.
Additionally, the cables will be very well insulated and chargers provided with high quality ground fault circuit interruption devices(GFCI).
 

FireMedic

‘20 3P-Red Rocket & ‘20 LRX-Falcon Heavy
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Sorry I hadn’t seen this discussed here tonight, but Rob from Tesla daily was reporting on a rumor that Tesla Shanghai would cut production from 20,000 to 16,000 per week…

This seems highly unlikely to me that it could be anything related to the “demand issue”; curious what you all’s thoughts are. I wasn’t able to timestamp the video but his rambling disclaimer starts at 9:25 and he discusses this rumor at around the 10:00 mark.

Why would they cut production from their most profitable factory when they could pull all sorts of demand levers but they haven’t.

Maybe a line upgrade? Or just a bogus rumor, or perhaps some impact from the sickness.

 
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For those of you invested in TSLA and SpaceX congrats. For those only invested in TSLA at least take solace that SpaceX is so profitable that you'll never have to worry about it pulling down TSLA.

New classified version of Starlink will be pulling in Trillions of dollars from the US government on top of all the existing contracts. Like more money than everything SpaceX has ever done.


1670042007096.png
 
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Prunesquallor

His cardinal virtue? An undamaged brain.
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Dec 19, 2018
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For those of you invested in TSLA and SpaceX congrats. For those only invested in TSLA at least take solace that SpaceX is so profitable that you'll never have to worry about it pulling down TSLA.

New classified version of Starlink will be pulling in Trillions of dollars from the US government on top of all the existing contracts. Like more money than everything SpaceX has ever done.


View attachment 880857
OMG

IMO:
”Earth Observations” = launch-on-demand spy satellites (continuous, low-altitude target overflights via distributed obs)
”Communications” = super-hardened battlefield comms network (Ukraine Starlink on steroids)
"Hosted Payloads” = low-cost test of experimental sensors, comms

Another disruption (the Lockheed/Northrup defense satellite duopoly).

Elon has made himself more indispensable to the US Government.
 

Dutchie

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Jun 9, 2013
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It’s embarrassing for me how little I understand voltage and amps and stuff given how much of an EV enthusiast as I am but as I recall they had previously stated that the costs of switching over the entire supply chain of electrical components from 400v to 800v were too great for the moderate gains that could be achieved for those types of passenger vehicles.

Which is to say, it’s not that 800v was bad, just that the improvements to the existing product line wouldn’t be that great and it would be a huge headache logistically.

But with long haul trucks and pickups with a significantly higher power demand that tow there is potentially enough of an efficiency improvement to build it out like that from the start?

That’s my interpretation but as I said, my electrical engineering is shite.
As for volts, current (amperes), resistance (Ohms) I always use the analogy to a water hose.
The current (amperes) is the volume of water
The voltage is the presdure of the water in the hose
Ohms is the diameter if the hose (resistance)

If you want more water (ampers) you can increase pressure (volts) or increase diameter of hose with same pressure (less ohms).

If you put a finger on end of hose than water will travel farther. The resistance increased (ohms) because of that the pressure (volts) increased but water flow (amperes) decreased. Water flow dictates the amount of work that can be done (Watts). The battery is analogous to storage like a tank of water.

Hope it helps
 

Singuy

Well-Known Member
Jun 28, 2018
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Sorry I hadn’t seen this discussed here tonight, but Rob from Tesla daily was reporting on a rumor that Tesla Shanghai would cut production from 20,000 to 16,000 per week…

This seems highly unlikely to me that it could be anything related to the “demand issue”; curious what you all’s thoughts are. I wasn’t able to timestamp the video but his rambling disclaimer starts at 9:25 and he discusses this rumor at around the 10:00 mark.

Why would they cut production from their most profitable factory when they could pull all sorts of demand levers but they haven’t.

Maybe a line upgrade? Or just a bogus rumor, or perhaps some impact from the sickness.

Wuwa's latest video description said Shanghai restriction from covid have intensified with blockade. Tesla is probably gearing up for closeloop with reduced staff.
 

Prunesquallor

His cardinal virtue? An undamaged brain.
Supporting Member
Dec 19, 2018
4,667
59,435
Houston/Galveston
Sorry I hadn’t seen this discussed here tonight, but Rob from Tesla daily was reporting on a rumor that Tesla Shanghai would cut production from 20,000 to 16,000 per week…

This seems highly unlikely to me that it could be anything related to the “demand issue”; curious what you all’s thoughts are. I wasn’t able to timestamp the video but his rambling disclaimer starts at 9:25 and he discusses this rumor at around the 10:00 mark.

Why would they cut production from their most profitable factory when they could pull all sorts of demand levers but they haven’t.

Maybe a line upgrade? Or just a bogus rumor, or perhaps some impact from the sickness.

Yeah, I didn’t know what to make of that. Rob was super-hesitant to say anything, he said it was from a single source who was usually reliable.
 

Singuy

Well-Known Member
Jun 28, 2018
7,647
73,890
US
Most likely related to a reduction of [email protected] gigashanghai.

"China's epidemic prevention and control has recently eased in other cities, but in Shanghai, the control seems to have intensified, we need to be tested for nucleic acid every day, and there is a constant blockade of neighborhoods, in the most lively pedestrian street of Shanghai, Nanjing Road. Where there were no partitions before, blue tin barriers have been built to isolate them, all of which makes us uneasy, and we fear that the neighborhoods we live in will be blocked off at any time, unable to come and go freely, or shipped off to such isolated places for forced quarantine and torturous days. No jobs, no income. Well, let's hope this doesn't happen and life gets better." -Wuwa posted 1hr ago

 
As if this year couldn’t get anymore weird…..

Ha ha yeah I just read and commented on a bunch of his posts, he was so pissy and teslas negative for the last two years after initially being as in love with the m3 as I was.

He coined the best phrases about it back then, i.e. 'drives like a jet fighter in 2D'. So true. Then eventually he dropped into the teslaq abyss, probably as he sees through some of the positive echo chamber bs and can't consolidate that overall this is all still good. So he found friends with his criticism with teslaq and ended up in the negative echo chamber instead.

And now that he finally got FSD some of the fud clouds of the deep teslaq abyss he dropped into evaporate and he sees it was not all as bad as the people around him made themselves believe. Let's see how long this lasts :) but he is an expert driver and so can truly appreciate what Tesla has done here, now that he actually got to try it himself.
 
Those who understand auto sales know that demand is limited only by price. It's those automakers who don't have room to lower prices further who will have to cut production. Tesla will constantly increase production for many years and sell every car they can make.

I'm repeating myself but some people still don't understand this simple concept but prefer to think about the auto market in a traditional manner in which all automakers are on an even footing, more or less. Even in a severe recession, new cars continue to sell at a level over 50% of strong years. Currently, Tesla only has around 2% of the market, not because there is only 2-3% demand, but because that's all they can make.
Well said. Another take is that Tesla will be building and ramping new Gigafactories for the next 7 or 8 years, scaling as quickly as humanly possible - a literal sprint (lasting a marathon) and the demand will simply dictate Tesla's gross margins. Recessionary times might command lesser margins, while good times might command greater margins. Either way, Tesla doesn't slow down until the factories are pumping out 20M vehicles per year. This is the mission and Tesla doesn't intend to flinch. Their innovation in scaling both manufacturing and the company allows this model to work, and the likes of which have never been seen before.
 
With all due respect, you cannot be serious. Five years puts us into 2018. Remember the horrifying Model 3 ramp and (according to Elon) looming bankruptcy? The ensuing ramp and Giga Shanghai exceeding all expectations? Model Y? Cybertruck reveal? Battery day? Two AI days? The stock being up by ridiculous amounts and being included in the S&P 500? Your "biggest two things in five years" honestly don't crack my Top 10 Biggest Things in 5 Years, and probably not the top 20 in the 9 years I've been invested in TSLA. With all due respect, choose your timelines more carefully next go round.


2018 stock traded sideways more or less. Threat of bankruptcy was talked about after. AI and battery day effecting stock price? Mmh, minimal at best. If you like I can change it to NEGATIVE effects of stock price? We are good here at identifying and talking about the positive catalysts, my post is to ensure discussion can ensue about negative catalysts. Glad you have been invested so long, and to be frank if the COVID drop or the most recent drop from Twitter nonsense doesn’t crack your top 10, well you just prove my point.
 
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