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  #251  
Old 11-16-2017, 06:10 PM
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I want a Model S which is not going to happen unless I win the lottery.
Go look on autotrader. You can pick up a Model S off lease for right around 38k.
  #252  
Old 11-16-2017, 06:13 PM
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Amusingly, they also commonly have problems with their battery. Not the big one, though. The standard 12v lead-acid that every Tesla still includes because all of the off-the-shelf components still run on 12v, and it's convenient to have a small buffer.
Yeah I read about that. I guess Tesla assumed the car would always (or nearly always) be plugged in when sitting, and didn't manage key-off load for the 12 volt electronics. repeated deep discharges will kill a lead acid battery in short order.
  #253  
Old 11-16-2017, 06:23 PM
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Yeah I read about that. I guess Tesla assumed the car would always (or nearly always) be plugged in when sitting, and didn't manage key-off load for the 12 volt electronics. repeated deep discharges will kill a lead acid battery in short order.
Actually, it doesn't matter if it's plugged in when sitting. Still slaughters the battery. The problem is that for fairly solid engineering reasons, the 12 volt lead acid battery is used to power the primary electronics as well as a bunch of accessories that Tesla can just buy from suppliers.

So the electronics draw right from that battery, discharging it, then periodically the DC-DC converter pulls power off the high voltage pack to recharge it. I do not know why it cycles and why they can't bypass that battery if the HV pack + DC-DC converter is healthy, but that's how it works in the S.

The issue is that this ends up being a discharge to about 50% and a recharge of the 12V battery a couple times a day. Doesn't matter if you plug it in. Eventually this causes the battery to fail - within around 6 months to a year and a half or so.

I read they "fixed" the issue by reducing the power draw from the electronics while the car is idle. This reduces how often the battery cycles and extends it's life to more usual numbers.
  #254  
Old 11-16-2017, 06:46 PM
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Actually, it doesn't matter if it's plugged in when sitting. Still slaughters the battery. The problem is that for fairly solid engineering reasons, the 12 volt lead acid battery is used to power the primary electronics as well as a bunch of accessories that Tesla can just buy from suppliers.

So the electronics draw right from that battery, discharging it, then periodically the DC-DC converter pulls power off the high voltage pack to recharge it. I do not know why it cycles and why they can't bypass that battery if the HV pack + DC-DC converter is healthy, but that's how it works in the S.

The issue is that this ends up being a discharge to about 50% and a recharge of the 12V battery a couple times a day. Doesn't matter if you plug it in. Eventually this causes the battery to fail - within around 6 months to a year and a half or so.

I read they "fixed" the issue by reducing the power draw from the electronics while the car is idle. This reduces how often the battery cycles and extends it's life to more usual numbers.
well then that's just stupid; every other hybrid/PHEV/EV has a 12 volt storage battery which they keep charged through a DC-DC converter, and none of those murder the battery. "Solid engineering" indeed.
  #255  
Old 11-16-2017, 07:17 PM
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well then that's just stupid; every other hybrid/PHEV/EV has a 12 volt storage battery which they keep charged through a DC-DC converter, and none of those murder the battery. "Solid engineering" indeed.
Well, it's still better than the Leaf where they "forgot" to put in proper thermal management for their main battery, causing it to die way faster than it should. And that battery isn't a $50 replacement.

I suspect the story is a little more complicated than is known publicly, anyway. Could easily be a combination of factors, each of which would have been fine on their own but combined led to worse-than-expected degradation.
  #256  
Old 11-16-2017, 07:20 PM
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Well, it's still better than the Leaf where they "forgot" to put in proper thermal management for their main battery, causing it to die way faster than it should. And that battery isn't a $50 replacement..
Whataboutism.
  #257  
Old 11-16-2017, 07:29 PM
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Dude, I'm the one that brought it up in the first place. I'm not completely oblivious to Tesla's failings. You're the one creating a strawman; no one ever claimed that Tesla's engineering is perfect. Everyone, no matter how big or well-respected, screws up sometimes. I'd be deeply suspicious of any organization that didn't make stupid errors from time to time.
  #258  
Old 11-16-2017, 07:43 PM
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Hopefully the Model 3 shares suspension parts with other Tesla's or better yet another manufacturer. The part that concerns me most is the electrical control module. It's a critical component that can't be found at a local parts store.

If they don't have any physical repair shops then they will have to farm out warranty work to existing garages. Probably a national chain they can contract with. They can warehouse parts the same way by partnering with a chain parts store.

What they can't afford in the short term is a major recall. If they don't have the infrastructure of full service dealerships then it's going to be chaos.
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  #259  
Old 11-16-2017, 08:01 PM
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Hopefully the Model 3 shares suspension parts with other Tesla's or better yet another manufacturer. The part that concerns me most is the electrical control module. It's a critical component that can't be found at a local parts store.
what, exactly, is the "electrical control module?" because modern cars have lots of those. the last bus query I did on a Lincoln Continental showed it had 40.
  #260  
Old 11-16-2017, 08:10 PM
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what, exactly, is the "electrical control module?" because modern cars have lots of those. the last bus query I did on a Lincoln Continental showed it had 40.
He means the drive unit motor control module. The thing that converts from high voltage DC at about 400 volts and supplies a 3 phase AC waveform to the drive unit, with 500 amps of current. Each channel uses dozens of silicon carbide mosfets, the whole thing is water cooled, etc. Verydifficult, virtually impossible to make a knockoff that meets any reasonable level of quality for safety standards at these power levels.
  #261  
Old 11-16-2017, 08:55 PM
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with 500 amps of current.
1500 amps.

The motor controller isn't repairable by "civilians". Fortunately, though, it's easily replaced as a unit. I dunno if Tesla will consider selling those parts to third parties.
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Old 11-16-2017, 09:19 PM
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what, exactly, is the "electrical control module?" because modern cars have lots of those. the last bus query I did on a Lincoln Continental showed it had 40.
the module that controls the electrical power to the motors.
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  #263  
Old 11-16-2017, 11:31 PM
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ok new Semis and Roadster, damn.
  #264  
Old 11-17-2017, 12:26 AM
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That was a pretty awesome presentation.

Semi:
500 mile range
0-60 in 5 seconds unloaded
0-60 in 20 s with 80k lb load
65 mph up 5% grade fully loaded
400 mile charge in 30 min
Lots of other goodies, like anti-jackknife torque vectoring and platooning.

Obviously, the unloaded 0-60 time is silly, but I think the loaded time is a serious benefit to both safety and courtesy. With CA onramps at least, trucks have a hard time merging safely into traffic due to their low acceleration.

Roadster:
0-60 in 1.9 s
0-100 in 4.2 s
1/4 mi in 8.9 s
250+ mph
620 mi range
200 kW-h battery

Looks fantastic, too. Only $250k to preorder...
  #265  
Old 11-17-2017, 12:29 AM
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Pics and stuff:
Semi
Roadster
  #266  
Old 11-17-2017, 04:21 AM
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He means the drive unit motor control module. The thing that converts from high voltage DC at about 400 volts and supplies a 3 phase AC waveform to the drive unit, with 500 amps of current. Each channel uses dozens of silicon carbide mosfets, the whole thing is water cooled, etc. Verydifficult, virtually impossible to make a knockoff that meets any reasonable level of quality for safety standards at these power levels.
#1 I don't need it explained to me as if I were a child, I know how these things work

#2 Magiver's concern is misplaced because every HEV/PHEV/EV has the same hardware and they're not failing left and right

edit: Oh, you can "reserve" the Roadster for $50,000, or the "founders series" for $250,000? Sounds like Tesla needs another interest-free loan.

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  #267  
Old 11-17-2017, 04:31 AM
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and I'm not the only one who thinks this is a sneaky way to raise capital:

https://jalopnik.com/all-the-questio...now-1820523237
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Old 11-17-2017, 05:18 AM
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edit: Oh, you can "reserve" the Roadster for $50,000, or the "founders series" for $250,000? Sounds like Tesla needs another interest-free loan.
At those prices, the size of the loan might total.... one MEEELLION dollars!
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Old 11-17-2017, 05:34 AM
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At those prices, the size of the loan might total.... one MEEELLION dollars!
check your math.

"If Iím reading this correctly, 1,000 ďfoundersĒ reservations at $250,000 a pop. Thatís basically a $250M capital raise for Tesla."
  #270  
Old 11-17-2017, 06:00 AM
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Thatís 1,000 reservations available, not 1,000 reservations made.

Maybe youíre right and thereís a bunch of suckers who will want this car... when it delivers in seven years or whatever.
  #271  
Old 11-17-2017, 07:25 AM
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1500 amps.

The motor controller isn't repairable by "civilians". Fortunately, though, it's easily replaced as a unit. I dunno if Tesla will consider selling those parts to third parties.
Where is your 1500 amp figure coming from?

I was calculating it as : 258 horsepower from model 3 drive motor. (from an EPA document)

745 watts per horsepower. 400 volts pack voltage. 258*745/400 = 480 amps.

Fun fact, in the industry I'm in, we've noticed a shortage of silicon carbide mosfets. To get 480 amps you need around 10-15 50-amp FETS per channel, which is around what people have found when tearing down model S motor controllers.
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Old 11-17-2017, 08:14 AM
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Where is your 1500 amp figure coming from?

I was calculating it as : 258 horsepower from model 3 drive motor. (from an EPA document)

745 watts per horsepower. 400 volts pack voltage. 258*745/400 = 480 amps.

Fun fact, in the industry I'm in, we've noticed a shortage of silicon carbide mosfets. To get 480 amps you need around 10-15 50-amp FETS per channel, which is around what people have found when tearing down model S motor controllers.
the Model S/Model X "P" variants.
  #273  
Old 11-17-2017, 09:45 AM
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the Model S/Model X "P" variants.
Right. I thought we were talking more generally about Tesla at that point. Tesla made a big deal of their 3D printed contactor rated at 1500 A.

In any case, the numbers presented are only valid in the power-limited case. At zero RPM, the current (for a finite power draw) can be arbitrarily high, limited only by the resistance of the circuit (including cell resistance), and potentially by cooling
  #274  
Old 11-17-2017, 09:58 AM
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and I'm not the only one who thinks this is a sneaky way to raise capital:

https://jalopnik.com/all-the-questio...now-1820523237
Oh look, another Ryan Felton article. What a surprise.

While I'm sure Tesla is happy to take people's money, it's not like $250M is going to make or break things. It's small potatoes. The point of the Roadster is not to make money (though it shouldn't lose money), but rather be a halo item. It's there to continue demonstrating that EVs can be superior to ICEs not just in efficiency but in virtually every way that matters.

As best I can tell, Tesla built a hell of a motor for the Model 3 and now they're using it for everything. The Roadster has three of them; the Semi has four; the AWD Model 3 will have two. So all of this extra stuff is, in part, a way of further amortizing Model 3 development costs.
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Old 11-17-2017, 10:39 AM
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How much utility does a semi with 300 miles of range have? Even 500? And batteries that size take a while to charge.

Delivery trucks with defined routes routes and batteries that can recharge between running routes as they are reloaded ... that makes sense. A semi?

Seems to me that Tesla needs to focus more on executing their current project well before moving on to the next big idea.
  #276  
Old 11-17-2017, 10:54 AM
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Seems to me that Tesla needs to focus more on executing their current project well before moving on to the next big idea.
Model 3 development is done. Now they're working on production. Semi production is a ways off, but they need to develop it now if they want to be ready a few years from now. Development and production are different people; you can't just arbitrarily move resources between them (though apparently they did temporarily steal some people on the semi project to help rewrite the pack assembly automation).

The semi will recharge 400 miles in 30 min. Refueling diesel tanks apparently takes 15 minutes, so this is hardly a difference at all.

One could argue that Tesla should have focused on shorter, local routes, but those are probably lower margin than long haul.

I think it's in Tesla's interest to find as many uses for their batteries as possible. Increased demand means more production at the Gigafactory, which means lower prices for everyone. Along with utility storage, the semi should be a big user--somewhere around 1000 kW-h per unit.
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Old 11-17-2017, 11:02 AM
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Oh look, another Ryan Felton article. What a surprise.
ad hominem. what's wrong with his analysis? That is, apart from not being complimentary enough towards Tesla.

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How much utility does a semi with 300 miles of range have? Even 500? And batteries that size take a while to charge.
for long haul? Dubious, but we'll wait and see. Long haul competitors like the Freightliner Cascadia and Kenworth T680 can carry 300+ gallons of diesel, and at roughly 8 mpg that's 2400 miles total range per fill. I believe the limit for truck drivers is 11 consecutive on-road hours, so hauling something cross country at 65 mph gets you ~ 700 ish miles before the driver is legally required to stop for rest. The Tesla would already be tapped out. at least for a while, this doesn't look like something an owner-operator would take a chance on.

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Delivery trucks with defined routes routes and batteries that can recharge between running routes as they are reloaded ... that makes sense. A semi?
that would make more sense, for a company-owned fleet with company-employed drivers (e.g. Wal*Mart, Meijer, etc.) The tractors are pretty much interchangeable, so drivers could make their deliveries, leave the tractor for recharging, and hop into a fully-charged one to take back to the warehouse. FCA does this with their regional inter-facility fleet except they run on CNG. Just roll trucks among drivers as they're fueled (on site) as available.

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Seems to me that Tesla needs to focus more on executing their current project well before moving on to the next big idea.
well, yes; it's rather strange to announce something like this while you're still scrambling putting Model 3s together with chewing gum and baling wire.
  #278  
Old 11-17-2017, 11:15 AM
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Model 3 development is done. Now they're working on production. Semi production is a ways off, but they need to develop it now if they want to be ready a few years from now. Development and production are different people; you can't just arbitrarily move resources between them (though apparently they did temporarily steal some people on the semi project to help rewrite the pack assembly automation).
your vehicle operations team should be involved in the design process from the start. you don't wait until you have a finished design then fire it over to manufacturing and say "here you go, design the assembly line." That work should have been nearly done back in March 2016 when they unveiled the first Model 3 prototypes.

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  #279  
Old 11-17-2017, 11:20 AM
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ad hominem. what's wrong with his analysis? That is, apart from not being complimentary enough towards Tesla.
There's nothing wrong because there is no analysis. Again, if Tesla is losing a billion per quarter, then how is $250M capital raise supposed to be significant? It's 3 weeks of burn rate. Ryan thinks that Tesla went through all the effort of building several prototype vehicles just to sustain the company for 3 more weeks? Not to mention that they're been talking about both of these things for several years now, so somehow they predicted back in 2014 or whatever that they would need 3 weeks of extra cash here in 2017, so they better get started soon.

It's all just ridiculous, conspiracy-level thinking.

As for the rest of the article, I'm not sure if he even watched the presentation. 0-60 times are fun to watch but the real point is that it comes for free when you have the power to maintain speed on significant grades. And that would well be important to truckers on many routes.
  #280  
Old 11-17-2017, 11:27 AM
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your vehicle operations team should be involved in the design process from the start. you don't wait until you have a finished design then fire it over to manufacturing and say "here you go, design the assembly line."
Sure, but the involvement will be small early on. It doesn't take the entire production team to point out the ways that the design needs to be modified to be manufacturable. Whatever production issues are left to be solved on the Model 3 aren't going to be affected by semi development at this stage.
  #281  
Old 11-17-2017, 12:39 PM
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Okay read more, and appreciate the responses.

Production slated for 2019, so call it 2021 or 2.

Recharging on the road supposed to be via a to be built "Megacharger Network" that somehow is to be solar powered? Someone help me out here. How big are these batteries? How much draw will it take to charge one to 80% in 30 minutes?

And one assumes that the longer term vision is to have the drag coefficient further improved upon by having these run as virtual trains with V2V and use of autonomous features, possibly with no driver at all in future iterations and likely just one for the whole train sooner than that. That however means a train of them wanting to charge all at the same time. Roughly calculating this out I think that comes to 2.3K shitloads of power all at once.

Or does a fleet operation run these old Pony Express style, each grouping running half an hour behind the one ahead, with now rested (charged for a half hour) Semis waiting at each Megacharger station?

I give credit to the Tesla team (and I think that means more than just Musk) for making no small plans ... but boy it is a leap of faith for any fleet or owner operator to go with this until Tesla proves the ability to deliver at least on the 3 and has some Megachargers built on the routes used already.

And if nothing else this gives the media something else Tesla to talk about than their production woes.
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Old 11-17-2017, 01:44 PM
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There's nothing wrong because there is no analysis.
that doesn't explain your dismissive "oh, another Ryan Felton article."

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It's all just ridiculous, conspiracy-level thinking.
ah, there it is. it's all a conspiracy to make Tesla fail.

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Okay read more, and appreciate the responses.

Production slated for 2019, so call it 2021 or 2.

Recharging on the road supposed to be via a to be built "Megacharger Network" that somehow is to be solar powered? Someone help me out here. How big are these batteries? How much draw will it take to charge one to 80% in 30 minutes?
I wonder if anyone understands just how much instantaneous power we're talking about to be able to charge 400 miles of range in 30 minutes.
  #283  
Old 11-17-2017, 02:08 PM
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Go look on autotrader. You can pick up a Model S off lease for right around 38k.
Not in Canada, certainly none that I've seen so far....
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  #284  
Old 11-17-2017, 02:39 PM
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well then that's just stupid; every other hybrid/PHEV/EV has a 12 volt storage battery which they keep charged through a DC-DC converter, and none of those murder the battery. "Solid engineering" indeed.
To be fair, we have this issue, too, at least, I experienced it when I had my Fusion Energi. I happened to have a lucky three-week spurt where the ICE never engaged once. One Saturday morning, the car was dead and I had to charge the 12V battery. Without the 12V, the high-voltage contactor wonít engage, and thus thereís nothing to charge the battery. What I donít understand, though, is why the 12V doesnít charge from the HV battery? Apparently it only charges when the ICE is running.

This could have been a bug affecting my unit only, but Iíd read about the issue on other forums from other Energi drivers.
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Old 11-17-2017, 03:01 PM
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To be fair, we have this issue, too, at least, I experienced it when I had my Fusion Energi. I happened to have a lucky three-week spurt where the ICE never engaged once. One Saturday morning, the car was dead and I had to charge the 12V battery. Without the 12V, the high-voltage contactor wonít engage, and thus thereís nothing to charge the battery. What I donít understand, though, is why the 12V doesnít charge from the HV battery? Apparently it only charges when the ICE is running.

This could have been a bug affecting my unit only, but Iíd read about the issue on other forums from other Energi drivers.
it's got to be a bug somewhere, e.g. a module didn't sleep and drained the battery. We have a Fusion Energi in my lab right now and I checked, when you turn the car on (w/o ICE running) the HV system lifts the 12V system to 13.5 volts. IIRC the '13-14 C-Max had some software issues causing 12V system run-down, don't know if the Fusion was affected too.
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Old 11-17-2017, 03:44 PM
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ICE can have the "computer left running unexpectedly" problem too.

A couple months ago I left a Bluetooth OBD dongle plugged into my switched-off ICE car overnight. Which apparently kept at least some of the computers on, although the instrument panel was dead dark when I left the car with the keys in hand. Next day was a dead battery. Let it jump-charge for a few minutes and haven't had a repeat.


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  #287  
Old 11-17-2017, 04:43 PM
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it's got to be a bug somewhere, e.g. a module didn't sleep and drained the battery. We have a Fusion Energi in my lab right now and I checked, when you turn the car on (w/o ICE running) the HV system lifts the 12V system to 13.5 volts. IIRC the '13-14 C-Max had some software issues causing 12V system run-down, don't know if the Fusion was affected too.
jz, most EVs have a large parasitic draw from their various computers. Yeah, they should all be sleeping, but features like remote start, remote firmware update, detecting the remote control when the owner approaches all require you to energize some of the electronics. Sloppy optimization on your power states can easily suck a ton of power - apparently Tesla sucked about 80 watts.

So what you just observed in the lab is consistent with what others experienced. The HV system only lifted the battery to 13.5 with the car on. If the battery were left at 13.5, or the HV system were to engage a bypass circuit or something, you could directly power the electronics with HV derived energy only*. Assuming an efficient DC to DC converter and good firmware that will hard kill all the electronics* if the HV state of charge ever gets too low, this would work.

*by opening a relay and having a startup circuit that can only start again if a charging plug is inserted into the charging port and supplying power.
*some lead acid battery chemistries don't do well with being kept at 13.5 all the time. The SLA in UPS batteries seem to do fine, and I think most EVs and hybrids use an SLA, however.

Last edited by SamuelA; 11-17-2017 at 04:45 PM.
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Old 11-17-2017, 04:47 PM
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Ya know, I'm kind of surprised more hybrid/PHEV/all electric cars aren't running supercaps instead of a lead acid 12v for this sort of thing. I suspect the answer is cost as it almost always is but supercaps offer a lot of advantages over stock car batteries. These Maxwell supercaps are what we use on some of our gensets and they're the bomb.
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  #289  
Old 11-17-2017, 06:33 PM
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jz, most EVs have a large parasitic draw from their various computers. Yeah, they should all be sleeping, but features like remote start, remote firmware update, detecting the remote control when the owner approaches all require you to energize some of the electronics. Sloppy optimization on your power states can easily suck a ton of power - apparently Tesla sucked about 80 watts.
80 watts is criminal. our standard for key off current draw is on the order of 0.01 amps.

Quote:
So what you just observed in the lab is consistent with what others experienced. The HV system only lifted the battery to 13.5 with the car on. If the battery were left at 13.5, or the HV system were to engage a bypass circuit or something, you could directly power the electronics with HV derived energy only*. Assuming an efficient DC to DC converter and good firmware that will hard kill all the electronics* if the HV state of charge ever gets too low, this would work.
except Balthisar was asking if the HV system kept the 12V battery charged only if the ICE is running, which is not the case. keep in mind this car has no alternator or any other belt-driven accessories.
  #290  
Old 11-18-2017, 08:16 AM
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... I wonder if anyone understands just how much instantaneous power we're talking about to be able to charge 400 miles of range in 30 minutes.
Well someone did the calculations to come up something slightly precise than my 2.3K shitloads of power. Still roughing it though.
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... this would equate to 800 kWh of energy consumed in 400 miles (644 km) of travel. Teslaís Megacharger would need to have a tremendous power output of 1.6 MW, or thirteen times the power level of a standard Supercharger to be able to replenish 400 miles of battery range in 30 minutes. ...
Actually not as bad as I thought considering they already have Supercharger stations able to charge 40 cars at a time. That's three of these charging at a time and for a while three at a time would likely be plenty. I'd also be surprised if they did not have a system in place to reserve the spots on the route at precise times and to have the vehicles controlled to hit them precisely as they are available.
  #291  
Old 11-18-2017, 09:13 AM
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#1 I don't need it explained to me as if I were a child, I know how these things work

#2 Magiver's concern is misplaced because every HEV/PHEV/EV has the same hardware and they're not failing left and right.
The module is the EV transmission. If there are limited service stations and parts are not available then the car goes nowhere. I don't share your confidence in Tesla. When I buy a car it's important that I can get it serviced if needed. It's not a small matter to me. Stuff breaks and my daily driver needs to be reliable and that means it has to be repaired in a timely manner.

Now if I was ultra wealthy and it was another toy in my collection then the new
sportster would be the ultimate driving machine and I mean the ULTIMATE driving machine. I'd drop $250,000 on it right now. It's a bargain at that price, and any potential warts be damned. I'd sign the Tesla fanboy registry without hesitation.

But this discussion is about the Model 3. A car that's a day late and a dollar of quality control short.
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  #292  
Old 11-18-2017, 09:41 AM
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Well someone did the calculations to come up something slightly precise than my 2.3K shitloads of power. Still roughing it though.


Actually not as bad as I thought considering they already have Supercharger stations able to charge 40 cars at a time. That's three of these charging at a time and for a while three at a time would likely be plenty. I'd also be surprised if they did not have a system in place to reserve the spots on the route at precise times and to have the vehicles controlled to hit them precisely as they are available.
that article does not say it can charge 40 cars at the maximum rate.
  #293  
Old 11-18-2017, 11:30 AM
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It is a 40 stall Supercharging station the purpose of which is to recharge the vehicles on the road in the shortest time possible. I guess they could have built it such that not all could be used at the same time, or if all plugged in would decrease the rate by some percent but I think it is reasonable to presume that all 40 can be used as advertised as Superchargers at the same time.
  #294  
Old 11-18-2017, 12:05 PM
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I don't doubt one can build a 40-connection Supercharger facility. I wonder how much challenge (AKA dollars) it will be for the local utility to drag that much continuous duty power capacity to wherever such a station is built.

As an example, the Florida Turnpike is a very limited access highway that runs the spine of Florida. When not passing through a big city, exits are 50-ish miles apart and service plazas with food and gasoline are about 100 miles apart. Pretty much every service plaza is in the middle of nowhere.

Last edited by LSLGuy; 11-18-2017 at 12:06 PM.
  #295  
Old 11-18-2017, 12:40 PM
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I don't doubt one can build a 40-connection Supercharger facility. I wonder how much challenge (AKA dollars) it will be for the local utility to drag that much continuous duty power capacity to wherever such a station is built.

As an example, the Florida Turnpike is a very limited access highway that runs the spine of Florida. When not passing through a big city, exits are 50-ish miles apart and service plazas with food and gasoline are about 100 miles apart. Pretty much every service plaza is in the middle of nowhere.
The advantage of being in the middle of nowhere and having wholesale access to batteries for storage and also to solar at wholesale (owning that company too), of course is that you can put up a whole bunch of solar and store it for use as needed, including at night.

Clearly they'd still use grid too (might even have a deal to sell some daytime power to them if it exceeds their demand and storage), but I do believe Musk that the vision is to have on site solar provide the bulk of the power demanded. The local utility will likely not be asked to provide much more than they would for any other truck stop.

I am rapidly becoming less skeptical. Convoys of these vehicles traveling V2V communication enabled tight, eventually completely autonomously, powered to no insignificant degree by solar produced and stored on site at Megacharger stops ... yeah, that makes sense and interstate cross country hauling is easier for an autonomous system than dealing with meatbag drivers on city routes. This more than the Tesla 3 may be the killer app.
  #296  
Old 11-18-2017, 01:07 PM
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It is a 40 stall Supercharging station the purpose of which is to recharge the vehicles on the road in the shortest time possible. I guess they could have built it such that not all could be used at the same time, or if all plugged in would decrease the rate by some percent but I think it is reasonable to presume that all 40 can be used as advertised as Superchargers at the same time.
Well, you'd be wrong. Supercharger stations have racks of charger modules, and it takes a certain number of those modules working in parallel to charge a single car at the maximum rate. There are not 40*(# modules required for max) in most or all supercharger stations. My evidence for this is unfortunately anecdotal, but there is a clear connection between arriving first to a supercharger station and the reported charging rate on the car's dash. (the algorithm they use doesn't split as more cars arrive, it instead makes latecomers charge slower)

Also, you don't necessarily get the max. It depends on the battery temperature, state of charge, and other factors. Finally, I think Magiver was saying over an entire thread that until superchargers are common as gas stations, we won't see EVs?

Well, he's totally wrong. There's a lifetime limit on supercharging because it destroys the battery, and the Tesla software limits you. Basically, you cannot own a Tesla and charge it exclusively through supercharging if you don't want the speeds to be throttled after a certain point.

Last edited by SamuelA; 11-18-2017 at 01:08 PM.
  #297  
Old 11-18-2017, 05:21 PM
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it's got to be a bug somewhere, e.g. a module didn't sleep and drained the battery. We have a Fusion Energi in my lab right now and I checked, when you turn the car on (w/o ICE running) the HV system lifts the 12V system to 13.5 volts. IIRC the '13-14 C-Max had some software issues causing 12V system run-down, don't know if the Fusion was affected too.
Thanks for checking. I'm pretty sure the Fusion was 2017. Most of what I read online from others was for the C-Max, so it could be the C-Max having an issue, the C-Max being more popular, or C-Max people being more vocal.

I chalk it up to growing pains, but if it happens to a real customer, I worry about their impression.
  #298  
Old 11-18-2017, 05:35 PM
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Thanks for checking. I'm pretty sure the Fusion was 2017. Most of what I read online from others was for the C-Max, so it could be the C-Max having an issue, the C-Max being more popular, or C-Max people being more vocal.
there was a flurry of TSBs on this for the C-Max.
  #299  
Old 11-18-2017, 08:14 PM
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Well, you'd be wrong. Supercharger stations have racks of charger modules, and it takes a certain number of those modules working in parallel to charge a single car at the maximum rate. There are not 40*(# modules required for max) in most or all supercharger stations. My evidence for this is unfortunately anecdotal, but there is a clear connection between arriving first to a supercharger station and the reported charging rate on the car's dash. (the algorithm they use doesn't split as more cars arrive, it instead makes latecomers charge slower) ...
Interesting. Trying to research for more than anecdotal I found that what they do is have a 145 kW cabinet split between two cars.
Quote:
Superchargers are normally installed in pairs, with two Ďstallsí (parking spots) wired to a single cabinet. If two cars are plugged in at once they have to share the available power; the maximum that one cabinet can ever deliver is 145kW, while a single car can use up to 120kW if it is completely empty. If both cars are already at a state of charge where they would be using less than half the available power then there is no effect, and both cars charge as normal. Otherwise, charging speed is reduced.
The sharing scheme gives priority to the first car to plug in. The first car will normally get as much power as it wants, with the second car to arrive getting what is left over (but with a limit so that the second car always gets at least some power, a minimum of about 30kW).
So a 40 stall operation has 20 units of 145kW each.
  #300  
Old 11-18-2017, 08:16 PM
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Interesting. Trying to research for more than anecdotal I found that what they do is have a 145 kW cabinet split between two cars.
So a 40 stall operation has 20 units of 145kW each.
Yeah, that agrees with what I read. It means that experienced Tesla operators are going to choose to park anywhere but next to another Tesla. Amusingly, the same algorithm people use when boarding a public city bus - only when every pair of seats has 1 occupant do people start sitting next to strangers.
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