I don't know of any evidence that reducing the charging rate will significantly increase the life of the charging components. The car was designed to be charged at 40-80A with AC charging, and of course much higher amps than that with direct charging at superchargers. Maybe dropping to 15-20A is reducing your stress but I doubt it's reducing the charging components' stress.
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For reference, I burned through 3 UMCs and finally told Tesla they had to replace my loosely-fitting charge port. (The new one is snug. Since then, no problems.) A lot of things can burn out the UMC... which indicates that it's a poorly designed piece of equipment, unfortunately.
Tesla still refuses to admit that the loose charge ports (present on early cars) were defective, even though other people had the same problem.
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If the update breaks something, they're warranty-bound to fix it -- or buy his car back from him.
He has a legitimate complaint. If Tesla's unwilling to fix it, Tesla should offer to buy his car back at its original sales price.
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I would expect this to generally address the problem, if done comprehensively.
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I should point out that I had this happen (along with all sorts of other charging problems and multiple burned-out UMCs) during the period when I had the defective chargeport.
Actually, qwk, your car was delivered less than a month after mine. I'll bet you your chargeport is defective. Is it kind of loose when you plug the cord in -- a lot of side-to-side slop? A good chargeport should be extremely rigid.
Demand that the chargeport be replaced, see if this fixes the problem.
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My actual charger was OK, but my chargeport was loose, the contacts behind it were corroded, etc. etc. qwk's car was delivered less than a month later than mine. I would expect that the entire chargeport apparatus would require replacement, if it hasn't already been replaced.
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That's because it's almost certainly Tesla's fault. The evidence is that the UMC is the weakest link in the circuit, and is skating on the edges of violating code. :-( Rather than fixing this, Tesla made a hypersensitive software algorithm, which reacts to stuff which no electrician dealing with a properly wired house would worry about. On top of this, people have had charger problems. And (like me) have had chargeport problems. Tesla has been slow to admit the existence of these problems and resistant to making the necessary replacements.
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You're not looking at the entirety of the evidence. There are people who report backing down who aren't even using the UMC (J1772 or HPWC), and there are tens of thousands whose UMC's are working without a problem. While I will agree that the UMC had a design problem that resulted in melting of the adapter which caused pins to loosen more, it is not the sole, nor primary reason that the car is reducing charge current. The number of reported UMC failures on this forum has dropped dramatically since the new adapters were put in place, to near-zero.
The charge port hardware coupling is a tough-to-engineer environment. It's extremely difficult to create a coupling that will carry 80 amps while - at the same time - remaining usable for daily plugging and unplugging. I've had my HPWC cable replaced twice because of the heat it generated (although I'd imagine with a contact cleaning kit I could have revitalized it a bit.
All that said, when the car backs off by 25%, it points to some type of problem in the electrical environment. Yes, it could be a piece of Tesla equipment causing the failures - charger, charge coupling, or EVSE - but that appears to be a bit random and less frequent than some here play it up to be; or it could be in the infrastructure feeding the EVSE; or it could be a misbehaving appliance. Bottom line - it's not something that should be ignored or should generate a request to Tesla to turn off the safety feature.
Cottonwood
Roadster#433, Model S#S37
Also remember that the car side of the charge port connection needs to handle up to 330 Amps on a Supercharger. On top of that the 330 Amps are DC which cause more corrosion problems than AC connections.
In 2.5 years of MS ownership, my personal experience with instances of the 25% back down in charging current are very few, and in every one of those, the cause was something on the line side causing Voltage jumps. I have tried to purposely put in multiple extension cords, adapters, etc to make the current reduction happen without success. While I could cause almost 10 Volts of IR drop, I could not force the current reduction with Ohmic losses.
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To me it's just a general rule of electric/electronic components: heat shortens their lifespan. You seem skeptical, so if you are really interested you can read more about it here or here. Actually Google will turn up a lot of research and results.
When using a supercharger you're not stressing your on-board AC charger - other parts are being stressed, which are probably not under stress when charging @ 40A at home since they take a much larger beating at a supercharger, so I'm not worried about them when I charge at home. However, at home, I do worry about the AC on board charger.
I do appreciate that the system is "designed" to take 40A, but in engineering-speak, that means that its failure rate (or MTBF) is larger than some acceptable value. You can increase your MTBF if you lower the stress on the components. It's all statistics, so that doesn't mean I can guarantee my charger will last longer than someone who only goes for a 40A charge, but statistically, I think it should.
And maybe all this is non-sense and like you said it's all in my head of course... :wink:
-- Greg
Cottonwood
Roadster#433, Model S#S37
I'd like to point out that the two people making the main complaints here are working with tested, known-good circuits, where there's basically nothing they can fix from the wall socket back (to the point where the electrical utility has refused to consider the possibility of problems on its lines). This means their problems are almost certainly on Tesla's end, whether UMC, chargeport, or charger. (This is also the position I was in when I was having problems.)
(And if they are actually problems with utility company wiring, the only way to prove it is to blow out a transformer or wiring at the electric utility's end, so Tesla needs to make that possible. :biggrin: )
(And if they are actually problems with utility company wiring, the only way to prove it is to blow out a transformer or wiring at the electric utility's end, so Tesla needs to make that possible. :biggrin: )
neroden, I'm just going to point back upthread because I explained how power companies "check" their service, and how a misbehaving appliance can cause this.
It is definitely NOT "certainly on Tesla's end". It very well could be an issue with a UMC (but the vocal have replaced them already). It very well could be an issue with a charge port (but you noticed that yours was loose and perhaps they would too). It very well could be an issue with a charger in the car, and they need to go look at it. But the issue stands that there are tens of thousands of people not having a problem and a very few who do. That makes it an exception, not the norm.
But I've explained it all already upthread - and the very vocal minority just refuse to listen because it's difficult to troubleshoot and isn't as simple as just having Tesla turn off safety features. I'm sorry you're unhappy again.
It is definitely NOT "certainly on Tesla's end". It very well could be an issue with a UMC (but the vocal have replaced them already). It very well could be an issue with a charge port (but you noticed that yours was loose and perhaps they would too). It very well could be an issue with a charger in the car, and they need to go look at it. But the issue stands that there are tens of thousands of people not having a problem and a very few who do. That makes it an exception, not the norm.
But I've explained it all already upthread - and the very vocal minority just refuse to listen because it's difficult to troubleshoot and isn't as simple as just having Tesla turn off safety features. I'm sorry you're unhappy again.
Of course it has to be Tesla's problem! Certainly not any of the underpaid and under-appreciated electrical contractors that did any of the premises or service wiring...
</sarcasm>
Honestly, though, I'm on the fence. I've had this dial back issue with my HPWC a few times (drop from 80 to 60A) while nothing else on my side of the meter could have possibly been the culprit (my HVAC being the only thing I can imagine being a large enough to make a difference that far upstream, and it was idle the last time this happened). I did all of the wiring between the service entrance panels and the HPWC myself, so, I know it's right and as good as it's going to get. As far as troubleshooting things on my end, I'm not really sure what else I could do.
My utility transformer appears to be shared with two other residences, each also with 320/400A service. Neither of them have EVs, and I don't think they have any large loads that would come close either. Nothing that far out should really have an effect on anything on my side of my meter.
IMO, Tesla's current-reduction algo needs some work. That's not saying it's always wrong, but I'd bet it has more false alarms than even early generation AFCI breakers.
</sarcasm>
Honestly, though, I'm on the fence. I've had this dial back issue with my HPWC a few times (drop from 80 to 60A) while nothing else on my side of the meter could have possibly been the culprit (my HVAC being the only thing I can imagine being a large enough to make a difference that far upstream, and it was idle the last time this happened). I did all of the wiring between the service entrance panels and the HPWC myself, so, I know it's right and as good as it's going to get. As far as troubleshooting things on my end, I'm not really sure what else I could do.
My utility transformer appears to be shared with two other residences, each also with 320/400A service. Neither of them have EVs, and I don't think they have any large loads that would come close either. Nothing that far out should really have an effect on anything on my side of my meter.
IMO, Tesla's current-reduction algo needs some work. That's not saying it's always wrong, but I'd bet it has more false alarms than even early generation AFCI breakers.
islandbayy
Active Member
I have evidence.
9 UMC's. Current one is now almost 1 year old.
First 8, I charged daily at 40 amps. First one delivered with car failed at 2 week point.
Varied times. But each and every one of the first 8 I used at 40 amps.
Current UMC, that is just a hair shy of 1 year old, I charge at 32 amps or less, accept when ABSOLUTELY necessary to recharge as quickly as possible. Most would last a month, then start causing errors.
Not, one, Single, Issue with my current UMC. I will also vouch, that temperature of the unit is considerably lower at 32amp.
You went through 8 UMCs in a year, and I am still on my first UMC after 20 months of charging at 40A every night. I have to think there is something different about our cars or our electrical service.
islandbayy
Active Member
Add me to the group of people that are experiencing Charge Reduction with absolutely no issues with the premises. Sort of, I shall explain.
My home, is on a highly over-loaded (Or at least, over-subscribed) transformer being shared with at least 7 homes. I'm only one with a EV. Winter, almost no Electric Loads from other homes, Summer, AC loads nail that transformer.
Now, HPWC is 1 ft from breaker box. HPWC connected to 100 amp breaker by 2AWG (Larger then specified by Tesla). Breaker box is 5 ft from meter, fed by 2/0. More then large enough for my 200 amp service.
Meter being fed by transformer by 2/0. Though, transformer is far away.
Voltage Sag. Start at about 240v at no load, at about 40 amp load, drops to about 230v, at 80 amp load, drops to about 222v. At my home, the car will stay at 80 Amps for about 5-10 minutes before reducing to 60 amps. Despite the voltage drop.
Now, at my parents motel, they have a 70kW transformer.
During the summer, that 70kW transformer is feeding their motel, and 2 houses. So 4x200 amp services and 2x100 amp services. During the summer, the transformer is really loaded, but utility wont upgrade it as it is handling the load.
Now, the HPWC currently online (Had to remove the second one, as we ran out of available service without adding a second meter. I am working to resolve this by swapping loads between breaker panels and meters for the motel).
That HPWC, is located on the garage of the "Beach House". It is fed by one of the 200 amp services, and has that all to itself.
HPWC is 12ft from garage breaker panel, fed by 2awg. Garage panel fed from main panel by 2/0 Aluminum at ~13ft run. House Fed by 2/0 Copper.
During the winter, with the Motel Closed, the total load on the 70kW transformer is about 10kW. Thats factoring in the main house, 2 houses across the street, and misalenous loads. Either way, it's next to nothing considering the transformers size.
Voltage at the HPWC is STRONG. Start off at about 245v. At 40 amps, about 238v, at 80 amps, about 235v. So MUCH MUCH MUCH less voltage drop then my home.
The car will stay at 80 amp for a maximum of 30 seconds before backing down to 60, despite the much less voltage drop.
In the second instance, at the motel, I have had the utility out, checked all the lines, transformer to the house etc... noting wrong, wiring proper size, tight connections etc...
Now, one other note, before removing (temporally until i get the load situation resolved) the second HPWC, I gave er a good test. Now, this second HPWC, was literally next to the breaker box, that was 2 ft from the meter, that is connected with 2/0 directly to the transformer. So a total wire run with oversized wiring, from HPWC to the Transformer, was less then 25Ft. I'd gather thats considered really dang close.
Same result when charging at 80 amps. about 30 seconds and it was already backed down to 60 amps. This test was done once season was over, and motel closed, so all large loads were gone (motel portion is completely electric, the houses use gas for heat, so no real loads from the houses).
Voltage drop measured: ~248 no load, ~242 at 40 amps, Fluctuating between 239 and 240v at 80 amp load. So extremely little voltage fluctuation.
Still, drop from 80 to 60 amps. Makes no sense. It will sustain 60 amps all day, but doesnt like 80 amps. Utility put some sort of line monitor. They were a little vague on the details of it, but it was to test for "Noisy" power and "hickups" is how the utility worker said it. I might also mention, the 10 megawatt hydro plant is 2 miles away.
No explanation as to why it happens.
in fact, the ONLY, and I will repeat, ABSOLUTELY ONLY HPWC IVE EVER CHARGED AT THAT I DID NOT GET CURRENT LIMITED WAS AT Marshall Auto Body. Shout out to Scott for his awesome setup.
He has a 80 amp HPWC, a I believe 70 amp J1772 Clipper Creek, 70kW Solar Array, and is in the process of completing a CHAdeMo install at his body shop.
I will need to take that statement back, the HPWC's at the Highland Park service center I did not get current limited. But in terms of Non-Tesla owned HPWC's, EVERY other HPWC or 80 amp charging location I've visited (And it's A LOT) other then Marshall Auto Body has gotten current limited at some point to 60 amps during the charge session.
Please don't take this as a argument. I'm voicing my findings in this thread, as I'd like to find a solution to this issue. I will also add, I have a retrofit dual charger. My car was shipped with single charger. At time of retrofit, my master was also replaced as it would not communicate with the slave. I have had duallies for exactly 1 year now.
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The one delivered with my car was a First Gen I know that, not sure what the second and third were, every one after that was a second gen UMC.
I do keep a spare just in case, the first failure scared me, as at the time, Public charging was almost non-existent.
But over the course of the UMC's, I did notice a direct correlation between how long they lasted, to the amperage I charge at.
While I have a HPWC now, I rarely use it. My car is a outside car, my garage, is mostly a "Warehouse" for my online business, so in order to get the HPWC cable to reach, half the car will be sticking out of the garage.
The UMC is more then enough, even when completly draining my battery. At 40 amps, I sustain about 235v on the UMC's circuit due to its run length to get all the way outside from my breaker box. 6 Awg at about 60 ft. As I lowered the amperage, so 39, 38, 37, 36 etc..., I noticed (Car under first year of ownership, UMC's are, at least according to Tesla, only under warranty for 1 year from purchase date of vehicle, or if ordered in the online store, 1 year from date of UMC purchase, no longer then that) that since the UMC was under warranty, experiment a bit with the amperage. Seems 32 was about the magic number. I usually charge much lower then this, 20 amps from 7pm to 7am is usually enough to give me a 90% charge on my 60kWh pack overnight, unless I get home much later.
I will add, UMC stays plugged in outside. It is in shade, and semi-protected from elements (rain) by a large roof over-hang.
My home, is on a highly over-loaded (Or at least, over-subscribed) transformer being shared with at least 7 homes. I'm only one with a EV. Winter, almost no Electric Loads from other homes, Summer, AC loads nail that transformer.
Now, HPWC is 1 ft from breaker box. HPWC connected to 100 amp breaker by 2AWG (Larger then specified by Tesla). Breaker box is 5 ft from meter, fed by 2/0. More then large enough for my 200 amp service.
Meter being fed by transformer by 2/0. Though, transformer is far away.
Voltage Sag. Start at about 240v at no load, at about 40 amp load, drops to about 230v, at 80 amp load, drops to about 222v. At my home, the car will stay at 80 Amps for about 5-10 minutes before reducing to 60 amps. Despite the voltage drop.
Now, at my parents motel, they have a 70kW transformer.
During the summer, that 70kW transformer is feeding their motel, and 2 houses. So 4x200 amp services and 2x100 amp services. During the summer, the transformer is really loaded, but utility wont upgrade it as it is handling the load.
Now, the HPWC currently online (Had to remove the second one, as we ran out of available service without adding a second meter. I am working to resolve this by swapping loads between breaker panels and meters for the motel).
That HPWC, is located on the garage of the "Beach House". It is fed by one of the 200 amp services, and has that all to itself.
HPWC is 12ft from garage breaker panel, fed by 2awg. Garage panel fed from main panel by 2/0 Aluminum at ~13ft run. House Fed by 2/0 Copper.
During the winter, with the Motel Closed, the total load on the 70kW transformer is about 10kW. Thats factoring in the main house, 2 houses across the street, and misalenous loads. Either way, it's next to nothing considering the transformers size.
Voltage at the HPWC is STRONG. Start off at about 245v. At 40 amps, about 238v, at 80 amps, about 235v. So MUCH MUCH MUCH less voltage drop then my home.
The car will stay at 80 amp for a maximum of 30 seconds before backing down to 60, despite the much less voltage drop.
In the second instance, at the motel, I have had the utility out, checked all the lines, transformer to the house etc... noting wrong, wiring proper size, tight connections etc...
Now, one other note, before removing (temporally until i get the load situation resolved) the second HPWC, I gave er a good test. Now, this second HPWC, was literally next to the breaker box, that was 2 ft from the meter, that is connected with 2/0 directly to the transformer. So a total wire run with oversized wiring, from HPWC to the Transformer, was less then 25Ft. I'd gather thats considered really dang close.
Same result when charging at 80 amps. about 30 seconds and it was already backed down to 60 amps. This test was done once season was over, and motel closed, so all large loads were gone (motel portion is completely electric, the houses use gas for heat, so no real loads from the houses).
Voltage drop measured: ~248 no load, ~242 at 40 amps, Fluctuating between 239 and 240v at 80 amp load. So extremely little voltage fluctuation.
Still, drop from 80 to 60 amps. Makes no sense. It will sustain 60 amps all day, but doesnt like 80 amps. Utility put some sort of line monitor. They were a little vague on the details of it, but it was to test for "Noisy" power and "hickups" is how the utility worker said it. I might also mention, the 10 megawatt hydro plant is 2 miles away.
No explanation as to why it happens.
in fact, the ONLY, and I will repeat, ABSOLUTELY ONLY HPWC IVE EVER CHARGED AT THAT I DID NOT GET CURRENT LIMITED WAS AT Marshall Auto Body. Shout out to Scott for his awesome setup.
He has a 80 amp HPWC, a I believe 70 amp J1772 Clipper Creek, 70kW Solar Array, and is in the process of completing a CHAdeMo install at his body shop.
I will need to take that statement back, the HPWC's at the Highland Park service center I did not get current limited. But in terms of Non-Tesla owned HPWC's, EVERY other HPWC or 80 amp charging location I've visited (And it's A LOT) other then Marshall Auto Body has gotten current limited at some point to 60 amps during the charge session.
Please don't take this as a argument. I'm voicing my findings in this thread, as I'd like to find a solution to this issue. I will also add, I have a retrofit dual charger. My car was shipped with single charger. At time of retrofit, my master was also replaced as it would not communicate with the slave. I have had duallies for exactly 1 year now.
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The one delivered with my car was a First Gen I know that, not sure what the second and third were, every one after that was a second gen UMC.
I do keep a spare just in case, the first failure scared me, as at the time, Public charging was almost non-existent.
But over the course of the UMC's, I did notice a direct correlation between how long they lasted, to the amperage I charge at.
While I have a HPWC now, I rarely use it. My car is a outside car, my garage, is mostly a "Warehouse" for my online business, so in order to get the HPWC cable to reach, half the car will be sticking out of the garage.
The UMC is more then enough, even when completly draining my battery. At 40 amps, I sustain about 235v on the UMC's circuit due to its run length to get all the way outside from my breaker box. 6 Awg at about 60 ft. As I lowered the amperage, so 39, 38, 37, 36 etc..., I noticed (Car under first year of ownership, UMC's are, at least according to Tesla, only under warranty for 1 year from purchase date of vehicle, or if ordered in the online store, 1 year from date of UMC purchase, no longer then that) that since the UMC was under warranty, experiment a bit with the amperage. Seems 32 was about the magic number. I usually charge much lower then this, 20 amps from 7pm to 7am is usually enough to give me a 90% charge on my 60kWh pack overnight, unless I get home much later.
I will add, UMC stays plugged in outside. It is in shade, and semi-protected from elements (rain) by a large roof over-hang.
So after the charger was replaced one year ago, you stopped having to replace the UMCs every month or so? Maybe this is more than coincidence.
Like I said in my previous post: it's a matter of probabilities.
Smoking every day is known to shorten your life expectancy, but that doesn't mean that every once in a while you can't find a centenary who will tell you he's smoked all his life and is feeling great.
If you understand the statistical model, then you can decide if you want to make use of it. You will find people who have charged every day for a year @ 40A with no problems, and people who have charged 1 day @ 10A and broke their UMC. But 2 data points are not enough to be statistically relevant.
-- Greg
When you say "I don't have voltage fluctuation", I have to ask how you measure that.
You are unlikely to be able to see the "voltage fluctuation" that the Tesla reacts to. This is especially true if you're relying upon the Tesla's screen or even a digital or analog multimeter. You need a more complex line analyzer - and in some cases a scope - to see the sub-second instantaneous voltage fluctuations that are triggering this algorithm. When I had the bad ballast in the shop, the Tesla showed voltage rock-solid at 235V. I can guarantee that the *only* load on the entire transformer was the Model S, and the shop's office light which consists of a single 8-bulb T54 fixture - 1 ballast per 4 bulbs. Every other load was turned off at the breaker panel.
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You can, however, draw conclusions based on the number of complaints versus the number of people who have purchased the car. It is indeed frustrating to see your charge current drop by 25%, as evidenced by those exceptional cases we're seeing here; so if this were happening at a higher occurrence than it is, you'd certainly see a much higher level of screaming than is currently seen here or on the Tesla Motors forums.
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islandbayy, have you asked your service center to have engineering look at your case? I think your willingness to help debug this is certainly something that Tesla could use as a solid data point. Connecting Tesla with your utility's engineering department (NOT repair, who will see if a light bulb lights up and call it good) to see why the car detects some type of a fault would be beneficial.
And I suspect it would lengthen the life of other devices attached to your utility connection.
islandbayy
Active Member
I've had current UMC about a 1-2 Months before getting the Master swapped and slave installed. Which was much longer already then I've had any previous UMC. Exact dateage is fuzzy.
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Didnt say I don't have voltage fluctuations, but very minor, within a volt or two.
I measure with a nice Multimeter I have (Not the Harbor Freight Special).
Also, like I said, utility put a special line monitor and reported no issues. No Blips dips or chips. Yah a scope would be nice
I have contacted We-Energies about my home, I just got back in from trudging through 2ft of snow to get to the pole with the transformer. Cant read the exact rating of it, but got some other informaiton off of it. First time I've been able to see it in person. Avoid going back their (In forest) during the winter due to snow and deer crap, and during the summer, too many leaves on trees to get a good look, and that neighbor is a jerk and chased me off his property last time I tried (hes not home now hehehe).
Now, I did, last year, work with a engineer. They did find a voltage problem, but not at the transformer. The actual sub-station my street was on was severely over-loaded. Moved my whole neighborhood to another substation (Took about 3 hours with power off for it to be done). They thanked me for finding that problem.....
As for the transformer, no idea what KW rating it has, it's old though. And set up strangely. Seems to be fed by a single wire and a strange attachment?????? I'm starting a new thread with transformer and pictures. It's a Allis Chalmers. But anyways, will be starting a new thread to try and figure that thing out. Either way, it's physical size is about the size of most 25kW transformers I see.
As for parents Motel, Alliant wont give me the time of day any more.
breser
AutoPilot Nostradamus
No they shouldn't. Tesla should buy it back after discounting the original sales price for use and damage. It's not like the owner didn't get some value out of the car for the time they had it. It's really absurd to suggest that any problem can have the owner demanding a full refund years later.
This sounds like a problem with the car not the HPWCs. I have a hard time believing that all of the HWPCs except a handful have had problems triggering current limits.
My experience with my first car was I always got 80A and never saw a current limit. Granted I had it for a limited period of time. With the 85D I'm having a weird issue where most of the time it only wants to charge at 79A on my HPWC (and I don't mean it only is showing 79A as the instantaneous amperage, I mean the selector lowers to 79A and it refuses to go to 80A). I mentioned this in my 85D thread and some P85D owners have come along and said they've had the same problem. Tesla is going to look into this issue for me on Monday, though today it let me raise it to 80A and stayed there. The P85D owners said the issue was intermittent for them. One of the P85D owners has another car that doesn't display the issue on the same HPWC.
I can't fathom what value a current reduction of 1A would have on an 80A setup. Before having had the 79A experience my opinion on this topic would have been very much that there's probably some real problem on these owners charging environments. But now I'm wondering if there aren't issues with Tesla's hardware and/or software. Yes I realize it's different behavior, but it opens the possibility that there are bugs in my mind.
I asked Tesla previously and here's what they said:
Occasionally mine shows 79/80A and occasionally it will go to the full 40/80. I suspect there's a bit of a rounding element in it plus accounting for the overhead.
Occasionally mine shows 79/80A and occasionally it will go to the full 40/80. I suspect there's a bit of a rounding element in it plus accounting for the overhead.
breser
AutoPilot Nostradamus
I don't think what you're talking about is what I'm talking about.
Both my S85 and my 85D (the one time I've seen it actually got to 80A) bounces between 79 and 80A on the view of what current it's currently pulling (what I referred to as the instantaneous amperage in the last post). However, on my 85D the selector (that you can lower your current to) drops down to 79A and stays there. Trying to raise it to 79A while plugged in does nothing. Unplugging, you can raise it back to 80A. Then you plug in and most of the time it goes right back to 79A. My S85 never ever did this. Two other P85D owners have said they had the same behavior. One made a video and sent it to me privately to see if we were talking about the same thing. The other told me his P85D does this but the other Model S in the household never does this.
Anyway I'm not trying to derail this thread by turning it into a discussion on this 79A issue, since I don't think it's really the same thing. I was just using this as an example that Tesla may have some problems in this area.
Made a new thread on this issue over here:
HPWC Charging Limited to 79A
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