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William13
Active Member
Yep, so you are seeing the same 90 kw cap as all other Sigs. Welcome to the club!
More info here: Older Tesla's limited to 90kwh super charging
I meant if there is 1-2% error in their (Tesla's) power sensors' accuracy, that could easily account for 122kW being reported (above the theoretical charger max of 120kW...)
Sure... I was just throwing out the other data point I had... it would be rather coincidental for the error to end up the exact same value on 2 different cars.
That having it been said, I've seen it reported here that the Tesla chargers (used in both the cars and the supercharger stacks) are actually capable of accepting 277VAC (a common commercial voltage) at up to 40A. That actually works out to be 11.08kW each.
Given the stack of 12 understood to be in each supercharger, that could actually deliver 132.96KW. So simply some supply-side line voltage fluctuation might allow them to put out slightly more than 120... provided the car was willing to accept it.
As a matter of fact, that figure rounds to 133kW... awfully close to the 135kW Elon mentioned in Europe...
hans
P631
I don't think you can compare the AC input to the DC output. There is loss and the US spec chargers cannot deliver 11 kW DC to the battery. More like 9.6 kW or so.
Actually, up to their limit for current and voltage, the AC input does affect output. That's why, for instance, HPWC's running on commercial 208V circuits only put out about 8.3kW per charger.
If your figure were correct, that world mean the stack of 12 chargers in a supercharger cabinet could only supply ~115kW...
Now that we have all but confirmed that this is a hardware limitation (Tesla has confirmed this twice to one of our members) there isn't much of a point in doing any more detective work to figure out what the maximum SC output is. I was holding out hope that this could have been causing the issue, but not any longer.
Now it's a question of how we proceed and determine why TM never communicated anything about a hardware issue to Sig owners.
Agree that there are just too many people who have used the newest Superchargers in numerous states and not seen more than 90kW (with numerous reports of others getting 120kW at these very same SCs) -- and the one thing these folks who are maxing out at 90kW have in common is that they are all Sigs or a few low VINs.
hans
P631
My figure comes from 240V x 40 A = 9.6 kW which is most AC input I can get on a single charger. I see less than that as DC input to the pack. I guess each charger must be able to go higher in a supercharger configuration though or as you say, the numbers don't add up. The North American chargers are quoted at 10 kW each and the Euro chargers are shown as 11 kW each so a stack of 12 of the Euro version chargers should be able to get ~10% more energy. I think thats how Elon gets from a high end of 120 kW in the US to the 132ish in the Euro superchargers.
Why would they? When the Model S came out we all thought that 90 kW charging was amazing. I don't remember anyone communicating their dissatisfaction with that. Then when they said the plug could support 120 kW and they could route all of the supercharger power to one car, that was even more amazing. It's likely they incorporated the necessary changes into the cars to support that at the same time.
Who knows whether handling 120 kW needs totally new power electronics and cabling, for example?
This sense of entitlement does seem a bit strange. You bought a MY1 car, so of course there will be improvements down the line. Did it meet your needs and expectations last year? I don't see Gen 1 Leaf owners demanding a heat pump just because the Gen 2 has it. Roadster sigs are a lot more crude than the later variants, but part of the deal with having the first cars off the line is they may well not be as refined as the end of the run.
I've got a Samsung Galaxy S3. It was an excellent phone last year and it's still an excellent phone, even though the S4 has a few tweaks that would be nice to have but in no way diminish the S3's usefulness and capabilities. Do I demand Samsung give me a free upgrade?
well I've been told by Tesla that the very early cars, basically all the sigs, are running with many 'prototype' parts that later production cars have better/newer versions. For example, things like older/different embedded ROM chips that run different firmware etc etc. Some (many?) of these cannot be "upgraded" (aka chips soldering into boards, not plug-and-play). so if sigs are limited to 90kWh charging , this isn't really surprising to me.
Yeah, most certainly, few of us will likely drive a single charger at more than 240V/40A at home (and many times the voltage will actually sag down to the 230's...). And certainly there are some losses due to charger efficiency.
My point is though, that in a supercharger, the input voltage will be higher, so with losses being a static percentage (say 10%), the resulting output will also be higher. While the chargers are quoted as 10 or 11kW, that actually may be stated as a result of expected input for typical residential usage.
The SC's can take 480V 3-phase input at 160A. See HERE.
Each phase to ground is a 277V feed at 160A. That means each of the 3 legs can supply 4 chargers with a 277V/40A input (i.e.- 11.08kW of power), for a total of 12 chargers in the stack.
I share you curiosity if that's how the Euro 135 number is derived though... it would seem that's not sufficient once you factor in losses. I'm not familiar enough with European commercial power to hazard a guess at the moment.
Cottonwood
Roadster#433, Model S#S37
Exactly! As an early Sig buyer (#37), I was very aware that this would happen. If this were a huge difference in charging time, then it would be important to me. However, as I stated before, its only about a 5 minute difference if you start at 0 miles. The taper goes below 90 kW at about 100 rated miles. 0 to 100 rated miles at 120 kW (400 mph) takes 15 minutes; at 90 kW (300 mph), it takes 20 minutes. After that, you are in the taper anyway.
I'm not getting too excited over a 5 minute loss in charge time for my early Sig. :wink:
mnx
2018 M3P
Again, it has been my experience that the time difference is much more than 5 minutes. Trust me, I have done my research here. Newer cars don't taper below 90 kw until 120 rated miles. My car tapers to 70 kw by 80 rated miles!
For me, supercharging is even slower than Tesla originally claimed. Therefore, I wasn't expecting 120 to be perfect, but I was expecting it to be noticeably different and fall more in line with what they originally claimed the SC network was capable of.
I was never told that my car is a prototype.
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