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What happened to my battery preheat?!!

Ostrichsak

Active Member
Sep 6, 2018
3,607
3,641
Colorado, USA
Or they figured out that it’s more efficient to skip the pre-battery heating and limit regen initially instead of preheating and having greater regen the first few miles. They did say the recent update would increase efficiency. Preheating the battery for a few miles of regen is probably not ideal from an efficiency perspective.

IMHO the proper way to implement this is a 3rd option under regen braking for "efficiency maximization" or something to that effect. Let the end user determine if they want it that way or not and default it to the standard but give those fringe outliers the ability to tailor it to their weird wants. They basically did this already when they added the ability for a few users to mimic the lower regen of an ICE car at the expense of efficiency so why not do it for the other side of the spectrum?

Personally, I don't care about a slight uptick in efficiency for the beginning of the drive it it results in such a jarring and varying driving experience.

In fact, I would like them to expand upon this so that people like me who live in colder climates can have the battery pack warmer when we set out so that regenerative braking is available at normal amounts from the start. On daily commutes where you use 10-15 miles this slight decrease in efficiency when your car is easily capable of 20x that distance is kind of pointless.
 
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Battpower

Supporting Member
Supporting Member
Oct 10, 2019
2,107
2,132
Uk
I'm just planning a week in the French Alps so I hope I don't get caught out the same way. 1 amp hardly seems worth the charging time.
 
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Sonny Daze

Member
Oct 21, 2016
955
1,048
DC
Battery preheat is broken in 2019.36.x and newer. I'm still on .32 because of that.

As we have it in the other threads already: from 2019.32 on there is no battery preheating on S and X any longer when preheating the cabin!

My S75D is still on 2018.50.6 and last week I left it outside unplugged overnight in 22F with range mode off and when I turned on cabin preheating in the morning through the app there was no battery symbol displayed.
 
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tyler2323

Banned
Dec 2, 2019
426
59
NV AZ CA
Most all of this is wrong. So much so that it's difficult to know where to start and it's especially annoying that you're attacking others who you claim don't know what they're talking about.

The gen 1 UMC will NOT allow you to manually set it to 40A draw on a 30A outlet. Never has. If you have a Tesla 30A adapter plugged into a 30A outlet the MCU will automatically lower the draw to 24A which is 80% of that circuits rating. You can't override this. Your entire soliloquy is void. The ONLY way you can run into trouble is if you make your own adapters for different outlets and override the UMC/adapters built in ability to cap draw based on the type of outlet. If you're smart enough to be building your own adapters I would hope that you're also smart enough to follow proper safety guidelines and properly set your draw limit each time though. Really no relevance to what you're talking about though.

The process where a UMC senses heat from an overloaded circuit and lowers draw to a safe range is present in BOTH gen 1 and gen 2 UMCs. Tesla never made a charger that didn't in fact and it would stupid of them to produce such a thing. The difference lies primarily in the components being analog v digital and the Gen 2 is far less expensive to make. There's a cost delta with several of the related components that made sense to have it only charge to 32A especially since it had been determined that most owners used their UMCs to charge their cars overnight so the real world difference between 32A and 40A was negligible. If an owner truly needed faster charging they likely would have a HPWC installed anyway.

There was a lot more in there that was completely false (your various battery pack heating scenario dangers are idiotic) but I think we've covered the important parts. The amount of rampant misinformation that is spewed on this forum as fact by people who clearly don't know the first thing of what they speak is staggering.

Before you ask, yes I own a P85D, yes it has dual chargers, yes I own Gen 1 UMCs and yes I've charged at just about every imaginable outlet type using them.

“The amount of rampant misinformation that is spewed on this forum as fact by people who clearly don't know the first thing of what they speak is staggering.”

This could not be more true with your lack of knowledge regarding the differences between Gen 1 UMC and Gen 2 MC chargers. And the purpose of making the Gen 2 MC and Gen 2 Wall Chargers.

The most common moronic misconception that is made about Gen 2 chargers, that it was simply made cause it’s cheaper. This is ridiculous and common sense should kick in to say that there has to be more logical reasons and concerns as to why Tesla would decide to make another charger.

First off the Gen 2 chargers are far more advanced than the Gen 1. The primary reason for making them was due to Gen 1 chargers overheating and the dangers associated with it (meting outlets, cords, connectors, etc that can potentially lead to fires) Gen 1 chargers have a completely different type of technology than Gen 2 chargers. Both will read the amount of amps of each outlet being used based on the adapters components. The difference between the two is much more advanced than just how much amps they are capable of using and the price they cost.

Gen 1 chargers have adapters with resistors built inside. Each type of Gen 1 Tesla adapter (i.e. 5-15, 15-50 ) has a resistor with a different value.
Gen 1 chargers uses these components to match the amps from the adapter to the outlet being used. Once the adapter determines what outlet is being used, it will signal to the car to limit the amount of amps it attempts to use based on the current rating of the outlet. The resistor is a bypass circuit and does not reduce the amps to the car if it starts to overheat etc. Running things like the heater, AC, max power etc can cause overheating. Also the higher amps it pulls the more likely it will overheat. Other factors like faulty wiring etc, can cause overheating as well obviously.

Gen 2 Chargers actually have a built in circuit board. The circuit board contains an advanced chip, has a memory, a temperature sensor, and supporting components. Using a circuit board makes the Gen 2 adapters much more advanced than the Gen 1 adapters. And Tesla uses all these different components to measure the temperature of the adapter’s plug, allowing it to reduce the charging amps if the adapter gets too hot until it cools down. On top of that Tesla can tell exactly what adapter is being used cause they all have a built in memory chip with a serial number.

As far as why they chose to limit the Gen 2 chargers to 32 amps has been a question of debate since the Gen 1 chargers were much more prone to overheating at 40 amps, it’s assumed that’s the reasoning. However the real reason is cause there is the possibility of a 40 amp outlet being used that the Gen 1 chargers would allow to charge to 40 amps. Hence 32 amps is 80% of 40.

If you ever took the time to research the Gen 1 chargers and all the information posted from owners experiences from melted outlets, connectors, handles, etc than you would realize why they made the Gen 2 chargers. It wasn’t cause of costs etc, there was very good reasons that most have the common sense to assume there would be.

Just on this forum alone you can find plenty of instances of owners having issues.
Here is a picture from a post from a member on here who’s gen 1 connector melted. Notice the color of the connector is gray. Either the ones that are gray or all black supposedly are less prone to overheating. I can’t remember if it was the all black or gray ones but the first time I had one that melted, I was using a 5-15 adapter. Slow charging at 11 amps cause it would actually get more miles at 11 amps than 12. Whichever one it was, Tesla had already known about supposed issues with that one, since the first thing they asked me was what color it was. They ended up replacing it with the safer one. The other time I was using one plugged into a 50 amp outlet and charging at 40 amps but had max power on, and the AC as well.

So really the only person attacking others would be the one commenting that it’s preposterous to say that Gen 1 chargers can lead to fires etc. Since the information is already out there showing many occasions when the cable was extremely hot or the connectors melted, etc. Or someone rambling off all the facts they assume they know about the 2 different charges but really have no idea, saying the same thing basically, how idiotic people are on here yet they themselves are the one who is greatly misinformed and spreading false assumptions rather than understanding the dangers.

Which doesn’t bother me cause I have no problem if someone doesn’t agree just don’t get mad when I give you the actual facts and have experienced the same issues with the Gen 1 chargers. Since most members may have no idea about the potential dangers, it takes real owners experiences to help others avoid potentially dangerous and deadly experiences from happening to them.

Also with Gen 1 chargers many owners will use adapters that are not made by Tesla that will charge at whatever amps they choose or they don’t realize what the amps have been preset too. Some owners had no idea the amps could even be adjusted. Here is a picture of someone charging 30 amps on a 30 amp outlet, I assume they are using an adapter which would not be compatible with the gen 2 charger based on how Tesla made the adapters. Which is why it was so common for owners to use adapters not made by Tesla when they owned the Gen 1 chargers.

The Gen 2 charger was specifically made to prevent owners from buying these adapters that would plug directly into a Gen 1 14-50 adapter. When using these adapters you can set a car to charge at as many amps as it is capable of.
Many owners who use these adapters do so cause they go camping etc, so they bought adapters to use based on what outlets were available. Not knowing the dangers associated with using these adapters especially if preset above what the outlet is rated for.

There also been owners who have posted the same experiences only using Tesla adapters that were able to charge past the amount the outlet was rated. There are clearly more problems with the Gen 1 chargers that most don’t know about which is why Tesla went the extra mile when making the Gen 2 chargers. If there was an instance of it allowing more amps or continuously overheating they have the information at there disposal with the ability to know every adapter being used based on the technology used to make them.

Just cause you have never experienced any issues doesn’t mean that it hasn’t and doesn’t occur. It’s obviously not something that occurs with everyone but Tesla has added ways to deter these things from happening, whether limiting the amount of amps it can charge, or dropping the amps when it’s overheating, to making them not compatible with third party adapters. These are all reasons why they made the Gen 2 MC since they have no control of the outlet being used.
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tyler2323

Banned
Dec 2, 2019
426
59
NV AZ CA
I can’t see Tesla taking away the battery heat intensity before cold departures. That doesn’t make sense? What’s in it for them? I would think a heated battery would be a better option than a cold one for first departure. I just recently moved to a cold place and was surprised that power was limited with a cold pack. I always knew regen was but was surprised to see the dashed yellow lines on the power side of the meter too.

on the surface it would seem a warm battery is a healthier one when operating the car?


Neither are good depending how extreme they are. The problem with heat is it causes the battery to swell. Especially if charging it to full and leaving it there or above 95%. In the heat you want to immediately drive it after charging to full.
If it gets as cold as some of the winter experienced last year like in Minnesota etc, it is awful for the battery.

If you have insane or ludicrous and put it on max battery than switch it back you will hear the fan cooling the battery immediately. Even if it’s cold outside
 

Ostrichsak

Active Member
Sep 6, 2018
3,607
3,641
Colorado, USA
Holy word wall Batman!

I'll see if I can address some of this continued misinformation presented as fact by someone who briefly scanned over a few posts in internet forums about this topic once and now considers himself an expert.

“The amount of rampant misinformation that is spewed on this forum as fact by people who clearly don't know the first thing of what they speak is staggering.”

This could not be more true with your lack of knowledge regarding the differences between Gen 1 UMC and Gen 2 MC chargers. And the purpose of making the Gen 2 MC and Gen 2 Wall Chargers.

The most common moronic misconception that is made about Gen 2 chargers, that it was simply made cause it’s cheaper. This is ridiculous and common sense should kick in to say that there has to be more logical reasons and concerns as to why Tesla would decide to make another charger.

That's not what I said so stop putting words in my mouth to try to make your point.

What I said was the gen 1 was analog components and the gen 2 version was digital. The digital component gen 2 version IS an upgrade over the gen 1. It's also less expensive to make which is the case for most every device that made the transition from analog to digital circuitry.

You keep trying to make it seem like gen 1 UMCs were burning houses down left and right and the truth is it never happened. The few times that outlets/plugs melted or got hot ended up being a problem with the outlet installation causing the problem in every instance I saw.

Also, for a self-professed expert on this topic I'm surprised you don't know that the "C" in UMC and HPWC stands for "Connector" and not "Charger" as you keep referring to them. Probably nit picking but it's a pretty glaring mistake for someone who knows everything. I bet you knew that though. Probably just testing me.

First off the Gen 2 chargers are far more advanced than the Gen 1. The primary reason for making them was due to Gen 1 chargers overheating and the dangers associated with it (meting outlets, cords, connectors, etc that can potentially lead to fires) Gen 1 chargers have a completely different type of technology than Gen 2 chargers. Both will read the amount of amps of each outlet being used based on the adapters components. The difference between the two is much more advanced than just how much amps they are capable of using and the price they cost.

Gen 1 chargers have adapters with resistors built inside. Each type of Gen 1 Tesla adapter (i.e. 5-15, 15-50 ) has a resistor with a different value. Gen 1 chargers uses these components to match the amps from the adapter to the outlet being used. Once the adapter determines what outlet is being used, it will signal to the car to limit the amount of amps it attempts to use based on the current rating of the outlet. The resistor is a bypass circuit and does not reduce the amps to the car if it starts to overheat etc. Running things like the heater, AC, max power etc can cause overheating. Also the higher amps it pulls the more likely it will overheat. Other factors like faulty wiring etc, can cause overheating as well obviously.

The first portion of this is accurate and almost a copy/paste from what I said. Good job!

The second half it comes off of the rails though with your stories of how much harder it is on the charger or car to run accessory type features of the car while it's plugged in. That's just dumb.

If you knew the first thing about electricity and these chargers you would know that 40A @ 240-volts is 40A @ 240-volts and absolutely no amount of items running in the car, the house, your neighbors or whatever changes that. Zero. Saying "obviously" in things like you have some idea what you're talking about doesn't help. You're wrong. Period.

Gen 2 Chargers actually have a built in circuit board. The circuit board contains an advanced chip, has a memory, a temperature sensor, and supporting components. Using a circuit board makes the Gen 2 adapters much more advanced than the Gen 1 adapters. And Tesla uses all these different components to measure the temperature of the adapter’s plug, allowing it to reduce the charging amps if the adapter gets too hot until it cools down. On top of that Tesla can tell exactly what adapter is being used cause they all have a built in memory chip with a serial number.

As far as why they chose to limit the Gen 2 chargers to 32 amps has been a question of debate since the Gen 1 chargers were much more prone to overheating at 40 amps, it’s assumed that’s the reasoning. However the real reason is cause there is the possibility of a 40 amp outlet being used that the Gen 1 chargers would allow to charge to 40 amps. Hence 32 amps is 80% of 40.

Yes, 32 is 80% of 40 so you aren't entirely wrong. Another gold star!

Now, as to why they arrived at 32A it wasn't just a guess or a dart on a dart board regardless of what you "assume".
Gen 2 UMCs are 32A because of the fact that some NEMA 14-50 outlets installed decades ago all over the country are wired only for 40A due to a previous stance on what the NEMA 14-50 standard was. As you're traveling around the countryside you may find a NEMA 14-50 on a 40A circuit and if you don't know what to look for. Connecting a Gen 1 UMC capable of 40A into a 40A circuit could create an unsafe condition much in the same way that connecting a Gen 2 UMC capable of 32A into a 30A outlet could in the hands of a moron. In both situations you're relying on the fail-safes to do their job and those aren't 100% so it's best to avoid those entirely through common sense.

The decision was made to go with a 32A continuous charger as it made the most sense. It also matched the majority of cars being manufactured at the time which also had less expensive AC chargers in them.... all in an effort to cut costs. Users who wanted higher charge rates would upgrade the onboard AC charger and likely install HPWC making for more profit... again financial decision in so many ways.

You keep saying it had nothing to do with cost but I see a bit of a pattern emerging here if you take your head out of the sand.

If you ever took the time to research the Gen 1 chargers and all the information posted from owners experiences from melted outlets, connectors, handles, etc than you would realize why they made the Gen 2 chargers. It wasn’t cause of costs etc, there was very good reasons that most have the common sense to assume there would be.

Just on this forum alone you can find plenty of instances of owners having issues.Here is a picture from a post from a member on here who’s gen 1 connector melted. Notice the color of the connector is gray. Either the ones that are gray or all black supposedly are less prone to overheating. I can’t remember if it was the all black or gray ones but the first time I had one that melted, I was using a 5-15 adapter. Slow charging at 11 amps cause it would actually get more miles at 11 amps than 12. Whichever one it was, Tesla had already known about supposed issues with that one, since the first thing they asked me was what color it was. They ended up replacing it with the safer one. The other time I was using one plugged into a 50 amp outlet and charging at 40 amps but had max power on, and the AC as well.

So really the only person attacking others would be the one commenting that it’s preposterous to say that Gen 1 chargers can lead to fires etc. Since the information is already out there showing many occasions when the cable was extremely hot or the connectors melted, etc. Or someone rambling off all the facts they assume they know about the 2 different charges but really have no idea, saying the same thing basically, how idiotic people are on here yet they themselves are the one who is greatly misinformed and spreading false assumptions rather than understanding the dangers.

I clearly have done my research and the accusation that I haven't only makes you look that much more foolish. I also have paid special attention to owner posts over the years here and at many, many other places online and in person.
The Gen 1 issue was the problem with the adapters and NOT the UMC itself. This is why they recalled all of the adapters for a few of the different outlets: NEMA 14-30, NEMA 10-30 and NEMA 6-50 with the black base. None of the others were involved in the recall because they were perfectly safe when matched to outlets/circuits that were properly installed to code. The "fires" and issues you speak of were directly related to the first version of these three adapters and revision 2 of those fixed that. No more issues. Even the frequency of those "issues" has been greatly exaggerated as there were only two of these reported prior to the voluntary recall of these three adapters that weren't adapters included with the UMC.

I never said that a Gen 1 UMC can't lead to fires but so can the Gen 2. To make it sound like it's more of an issue or that the Gen 1 UMC is somehow a widow maker is simply wrong. No other way to explain that. In most of the issues where someone's plug melted it was actually the home's wiring that was the culprit. In almost every case I've seen of overheated plugs (gen 1 or gen 2) the outlet is the problem with the wiring (not proper size) being 2nd most frequent. In that instance it doesn't matter if you use a gen 1 or a gen 2 if the wiring is done improperly.

Often times it's a homeowner that throws a NEMA 14-50 in and does the proper break, wire and all components are to code but the installation is done improperly. In these instances, you will see that the wire isn't stripped completely of insulation so when they tighten the outlet's lug down on the wire a little tiny strip of it gets caught in the contacts. This will create resistance at that point in the circuit and if you know anything about electricity (I assume you don't based on some of the things you've said so far so) resistance equals increased heat. Heat in and of itself isn't bad but there's a limit to what is considered excessive and excessive heat can be dangerous.

In just about every case I've seen of melted or overheated outlets the home owner's wiring was to blame. This same thing can happen with a Gen 2 although the potential for failure would be 20% less based on the sustained draw difference. Again, we're talking about rate of failures due to improper wiring so the issue STILL Isn't the UMC.
That doesn't mean it's not possible nor did I say it wasn't. These items are man-made and men make mistakes. I'm just not buying your claim that gen 1 UMCs are death traps and the UMC gen 2 is flawless and that was the motivation behind the update because I know better.

This is largely conjecture an assuming to know what most of the failures are since I haven't seen ALL failures first-hand but if you can assume based on zero information why can't I assume based on some information?

Which doesn’t bother me cause I have no problem if someone doesn’t agree just don’t get mad when I give you the actual facts and have experienced the same issues with the Gen 1 chargers. Since most members may have no idea about the potential dangers, it takes real owners experiences to help others avoid potentially dangerous and deadly experiences from happening to them.

Also with Gen 1 chargers many owners will use adapters that are not made by Tesla that will charge at whatever amps they choose or they don’t realize what the amps have been preset too. Some owners had no idea the amps could even be adjusted. Here is a picture of someone charging 30 amps on a 30 amp outlet, I assume they are using an adapter which would not be compatible with the gen 2 charger based on how Tesla made the adapters. Which is why it was so common for owners to use adapters not made by Tesla when they owned the Gen 1 chargers.

The Gen 2 charger was specifically made to prevent owners from buying these adapters that would plug directly into a Gen 1 14-50 adapter. When using these adapters you can set a car to charge at as many amps as it is capable of.Many owners who use these adapters do so cause they go camping etc, so they bought adapters to use based on what outlets were available. Not knowing the dangers associated with using these adapters especially if preset above what the outlet is rated for.

There also been owners who have posted the same experiences only using Tesla adapters that were able to charge past the amount the outlet was rated. There are clearly more problems with the Gen 1 chargers that most don’t know about which is why Tesla went the extra mile when making the Gen 2 chargers. If there was an instance of it allowing more amps or continuously overheating they have the information at there disposal with the ability to know every adapter being used based on the technology used to make them.

Just cause you have never experienced any issues doesn’t mean that it hasn’t and doesn’t occur. It’s obviously not something that occurs with everyone but Tesla has added ways to deter these things from happening, whether limiting the amount of amps it can charge, or dropping the amps when it’s overheating, to making them not compatible with third party adapters. These are all reasons why they made the Gen 2 MC since they have no control of the outlet being used.View attachment 494015View attachment 493892 View attachment 493893 View attachment 493891

Just because someone had something happen to them doesn't mean the know the first thing about why it happened. Experiencing a problem doesn't make you an expert. I don't have to burn a house down due to faulty electrical work to know how to prevent it. Likewise, a homeowner can have their house burn the ground due to improperly electrical work and still not know the first reason why.

Homemade adapters can be used for BOTH gen 1 and gen 2 so this entire portion is wrong. Again, if you knew half as much as you claimed you would already know that. Most people use NEMA 14-50 adapters supplied by Tesla for their homemade adapters which allows for 50A. They then manually decrease the amps in the car via the MCU to match whatever outlet they're plugged in to. If you don't do this you can cause a potentially unsafe condition in BOTH the Gen 1 and Gen 2. In your "photographic proof" of how "dangerous" the Gen 1 UMC is this could have just as easily been done with a Gen 2 UMC.

In fact, the car pictured in your "mic drop pic" happens to be a Model 3 if you look a the background. Gen 1 UMCs never came with the Model 3 so odds are pretty good that your picture actually proves my points that Gen 1 and Gen 2 possess equal potential for danger in the wrong hands and also that you have no idea what you're talking about. You're trying awfully hard to prove how much more dangerous Gen 1 UMCs are than Gen 2 UMCs to support your stance but it's just not the case.

I covered homemade adapters earlier in my post that some people create their own adapter kit to cover more uncommon outlets and most that go to that effort either 1) know what they're doing or 2) learn what it is they're doing because they understand the dangers of not knowing when you effectively remove/bypass safety features that the manufacturer put in. The idiot who knows not what he's doing and also doesn't take the time to educate himself on what he's doing and STILL bypasses safety features will is practicing a dangerous game that could end in burning himself, his car and house to the ground.

This is the same between Gen 1 and Gen 2 so saying otherwise is just more proof you're clueless. The most accurate things you've said are just paraphrasing things I already said.

You should just quit while you're behind. Every post you make you dig your hole deeper. I'd resist the urge to try to lash out and save face because you're only making things worse by supplying even more misinformation as fact.
 

David29

Supporting Member
Supporting Member
Aug 1, 2015
2,259
1,911
DEDHAM, MA
Today, I preheated the car before leaving to do errands. It was not terribly cold out (mid or high 30s, maybe) but my car was parked outside overnight and was not used at all yesterday, so the battery could have been quite thoroughly chilled. When I first started the cabin heater, the battery heater indicator lighted up in the phone app, but when i looked at it again just a few minutes later, it was gone. So, either the car decided that little to no heating was needed today, or this is another data point on the observations above that the battery heater is not running, or not running as much as before. (I had not carefully watched for the battery heating indicator on other recent cold starts, until I read through this thread.) I might need a colder day to be sure there is a change in behavior.

I have belatedly realized that I have been making a mistake in using the phone app. What I thought was the battery heating indicator must be the defrost indicator -- it is a small windshield-shaped indicator to the right of the word "CLIMATE" on the phone screen. I tested it by starting the defroster using the Defrost button at the bottom of the screen.
I do remember seeing a separate battery indicator, but I now realize that I have not seen it for a long time and can't recall what it looks like! It is possible that i have not seen it at all this winter. So, my apologies for the incorrect report.
 
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Dec 7, 2019
218
149
Toronto
One of the apps I use called Tesla Plus will show you if the battery heater is on or off real time. I find that its on for 20 min of my morning commute (in Toronto) of my 30 min drive. At the 30 min mark my regren bars are almost or completely gone (unless i drive very aggressively but its at 5:30am so I am trying to stay awake still). If you scroll down on the app it goes into console mode and it shows you all the actions the car is taking real time.
 
Dec 7, 2019
218
149
Toronto
Thought I should add. I use the ‘depart by’ feature which seems to work well (bringing me from 50-80% buy my departure time). This also warms the battery but the heater still comes on when driving.
 

Sonny Daze

Member
Oct 21, 2016
955
1,048
DC
My S75D is still on 2018.50.6 and last week I left it outside unplugged overnight in 22F with range mode off and when I turned on cabin preheating in the morning through the app there was no battery symbol displayed.
CORRECTION

I read some older posts and learned that the battery symbol may take some time to appear, so I tried again Wednesday night (26F) and sure enough, after a few minutes the battery symbol did appear when I preheated the car Thursday morning.
 

zambono

Active Member
Mar 1, 2016
1,160
607
DC
I've had my Model S for a few years now so lets get the "this happens every winter" people away from their quick responses of 'this is what happens to regen braking every winter. I've checked with some locals and they too have more aggressive regen limiting and no battery preheat.

The past few years in winter when I would preheat the car via the mobile app the battery heater icon would show up and the car would have at LEAST a little regen braking when I was ready to leave. This year I have zero battery preheating unless the car has been sitting for a LONG time in temperatures below 15 degrees. However even then the battery heater icon only shows up for a short period and nowhere near long enough to gain any regenerative braking.

Something was done to the software on purpose. I say on purpose because the heater does still activate but under new circumstances just seemingly at new temperature set points. Why? I have no idea but no regen, burning through my brake pads on a 20 mile hilly backroad commute is bull. I have the excess energy but instead I'm being ushered into a $175 hour Tesla shop fee brake job. No thanks. So for the past month or so I've been sitting in the car with the it "navigating to a supercharger" to trick the system into preheating the battery in anticipation of a supercharge. The car is willing to preheat the battery if it means alleviating Supercharger congestion aka bad press for Tesla but unwilling if they can gain some money on a brake job. I thought the service centers were not supposed to be a source of revenue? Right.

*Side note some real bad debugging. When I preheat the seat heaters don't come on until I've actually sat in the car. When I turn the car on the HVAC reverts to the settings I had when I left the car (completely ignoring what I had set the HVAC to via the app) and at times the seat heaters don't follow my selection. I've had a burning hot seat at level one while other times having no output on level3. It seems to correlate more withe the temperature I've asked for and the 3 seat heat levels are actually just a on/off placebo switch.

The constant meddling with software, removing and adding features, while screwing other functions up has left me strongly debating staying with Tesla despite following the company since its inception. I used to be excited by software updates. Now I cringe pressing the update button not knowing what may get broken this time in exchange for slapstick "comedic" flatulence or tacky backseat romance in dash fireplaces. I loved this company and admire their mission to move us away from fossil fuel consumption. It's a business yes but I'm wondering if it's become more about the money and twitter headlines on new products. A year from now when I have to make a choice to stay with Tesla or switch brands I hope Tesla gets its act together.

Cant wait for the Etron GT to have at least 300 miles and charge over 200kW.
 

whitex

Well-Known Member
Sep 30, 2015
6,705
8,047
Seattle area, WA
The Gen 1 issue was the problem with the adapters and NOT the UMC itself. This is why they recalled all of the adapters for a few of the different outlets: NEMA 14-30, NEMA 10-30 and NEMA 6-50 with the black base. None of the others were involved in the recall because they were perfectly safe when matched to outlets/circuits that were properly installed to code.
This is not entirely true, Tesla recalled my NEMA 14-50 adapter (they sent me a new one in a different color scheme and asked for the old one back in the same shipping box with pre-paid shipping). I don't remember exactly when or whether it was for my 2013 UMC or 2015 UMC, but they did recall at least some NEMA 14-50 adapters.

This same thing can happen with a Gen 2 although the potential for failure would be 20% less based on the sustained draw difference.
Actually, the likelyhood of a failure goes down a lot more than 20% with the 32A choice.
  • For NEMA 14-50 on 40A circuit 32A sustained load is safe
  • For NEMA 14-50 on 30A circuit, 32A load should trip the breaker, alerting the owner something is wrong
The only issue remains when someone plugs in UMC Gen2 into NEMA 14-50 on 30A breaker, and manually adjusts the amperage to 30A (or technically anything over 24A), but that is going to be rare, and requires deliberate user override action (vs. before you just plug-in and the default choices were potentially dangerous).

A few of side notes:
  1. Tesla made the 32A choice before Gen2 adapters were released. Gen1 chargers in Canada were firmware limited to 32A. This was done after an incident in Toronto where someone had a NEMA14-50 on a 40A circuit (which is perfectly legal by electrical code, but as you say, can be dangerous when subjected to 40A load for hours at a time).
  2. I've been charging at 40A daily using NEMA 14-50 since 2013 without any problems (I have a HPWC to install, but it didn't come in time to install with another one I was installing for my wife's Tesla, so it's been on backburner for a while now, UMC works just fine). AWG 6 wiring, 50A circuit, the adapter and wiring gets warm to touch but nothing dangerous (also confirmed with FLIR camera, which I use every year or so when I do a quick inspection of the house, looking for water leaks, any wiring which may be overheating, etc). Note that I very rarely unplug the UMC (less than 10 times since installation), so there is little wear on the NEMA 14-50 socket, which I understand can become an issue if someone unplugs/replug daily (a lot of NEMA 14-50's are designed for dryers, so not for high number of unplug-plug cycles which can cause wear which in turn can cause poor connection between the UMC adapter and the socket).
  3. The issues of home-made adapters is purely an issue of someone who doesn't know what they are doing attempting electrical work. It is no different that doing this ;)
chrismas tree plugs.jpg
 
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Ostrichsak

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Sep 6, 2018
3,607
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Colorado, USA
This is not entirely true, Tesla recalled my NEMA 14-50 adapter (they sent me a new one in a different color scheme and asked for the old one back in the same shipping box with pre-paid shipping). I don't remember exactly when or whether it was for my 2013 UMC or 2015 UMC, but they did recall at least some NEMA 14-50 adapters.


Actually, the likelyhood of a failure goes down a lot more than 20% with the 32A choice.
  • For NEMA 14-50 on 40A circuit 32A sustained load is safe
  • For NEMA 14-50 on 30A circuit, 32A load should trip the breaker, alerting the owner something is wrong
The only issue remains when someone plugs in UMC Gen2 into NEMA 14-50 on 30A breaker, and manually adjusts the amperage to 30A (or technically anything over 24A), but that is going to be rare, and requires deliberate user override action (vs. before you just plug-in and the default choices were potentially dangerous).

A few of side notes:
  1. Tesla made the 32A choice before Gen2 adapters were released. Gen1 chargers in Canada were firmware limited to 32A. This was done after an incident in Toronto where someone had a NEMA14-50 on a 40A circuit (which is perfectly legal by electrical code, but as you say, can be dangerous when subjected to 40A load for hours at a time).
  2. I've been charging at 40A daily using NEMA 14-50 since 2013 without any problems (I have a HPWC to install, but it didn't come in time to install with another one I was installing for my wife's Tesla, so it's been on backburner for a while now, UMC works just fine). AWG 6 wiring, 50A circuit, the adapter and wiring gets warm to touch but nothing dangerous (also confirmed with FLIR camera, which I use every year or so when I do a quick inspection of the house, looking for water leaks, any wiring which may be overheating, etc). Note that I very rarely unplug the UMC (less than 10 times since installation), so there is little wear on the NEMA 14-50 socket, which I understand can become an issue if someone unplugs/replug daily (a lot of NEMA 14-50's are designed for dryers, so not for high number of unplug-plug cycles which can cause wear which in turn can cause poor connection between the UMC adapter and the socket).
  3. The issues of home-made adapters is purely an issue of someone who doesn't know what they are doing attempting electrical work. It is no different that doing this ;)
View attachment 496169
Agreed. The 20% was just a rough idea to assign a value to discuss but I would agree that it probably isn't as simple as a linear difference but it's not that far off in the grand scheme of things. We should also be careful to mention that breakers don't ALWAYS trip if an excessive load is present. Like anything, they can fail and do and bag things can happen. Taking the proper precautions on the front-end to avoid needing them at all is the most safe way to approach circuits.

It was difficult to address this guy's word wall of inaccuracies and try to keep it succinct and accurate. I think I did pretty well given the mountain of misinformation I was attempting to address. I'll take a 98% accuracy rating on that novel I had to write. I thank you for taking the time to actually read it and catch anything I may not have been 100% accurate on. The last thing I want is to perpetuate the spread of misinformation during my attempt to address/correct it.

I also use a UMC daily which is plugged into a NEMA 14-50 outlet that I installed on a 50A circuit breaker directly below our panel. This has been more than enough coupled with one of the standard 15A convenience outlets for both of our cars so the two HPWC I have still remain in their boxes, much like yours. We also leave it plugged in though as the cheaper outlets can start to develop contact issues with the prongs of the adapter over time. This excess heat can cause issues but for people that just leave them plugged in all of the time it shouldn't be an issue. If you plan to plug/unplug daily for many years I'd recommend getting a more robust 14-50 outlet but, even then, these things are rated for thousands of plug/unplug cycles so it really shouldn't be an issue. Just check them out from time to time either way.

Someday I'll make the effort to upgrade the service coming into our house, upgrade the panel our entire house is on and install a new 100A breaker to run these two HPWC (and possibly a 3rd) but as of right now I can't see the benefit to doing so being anywhere near as the cost it will entail.

Sure it would be nice to downgrade our UMCs to purely mobile use when traveling and clean up the walls/floors but until we have a 3rd vehicle or our daily needs increase drastically I have very little motivation to change what works. Just the regular inspection as you mentioned and things just keep on humming along.
 
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whitex

Well-Known Member
Sep 30, 2015
6,705
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Seattle area, WA
I also use a UMC daily which is plugged into a NEMA 14-50 outlet that I installed on a 50A circuit breaker directly below our panel. This has been more than enough coupled with one of the standard 15A convenience outlets for both of our cars so the two HPWC I have still remain in their boxes, much like yours.

[...]

Someday I'll make the effort to upgrade the service coming into our house, upgrade the panel our entire house is on and install a new 100A breaker to run these two HPWC (and possibly a 3rd) but as of right now I can't see the benefit to doing so being anywhere near as the cost it will entail.

Sure it would be nice to downgrade our UMCs to purely mobile use when traveling and clean up the walls/floors but until we have a 3rd vehicle or our daily needs increase drastically I have very little motivation to change what works. Just the regular inspection as you mentioned and things just keep on humming along.
Don't feel bad. I actually installed a 100A circuit, a giant safety interrupt switch for it, and even a junction box for the second HWPC, but because Tesla took months to send it to me (referral), I ended up installing only the one I had. But, the UMC has worked so well that I felt no need to spend a day running the last part of the 100A from the junction box to the second HPWC when it finally arrived. If I was to get a 3rd Tesla in the house, I would definitely install 3 HPWC's, mostly to balance the charging current between the cars, but until then, not feeling much motivation to do that (have plenty of other projects I can do instead). Also, in the next year or so I might jump ship to a non-Tesla EV, and if so, that will require a different charging setup.

Oh, and even though each of our Tesla's has a UMC permanently in the trunk (I have an extra one), I have to tell you I don't think they were ever used outside of the house, except one time when I drove across the country, but even then I only used it at my final destination - the home where I was staying for a couple of weeks (knowing I was bringing my Tesla, my dad installed a NEMA14-50 for me in the garage).
 
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GSP

Member
Supporting Member
Dec 28, 2007
2,575
804
. Gen1 chargers in Canada were firmware limited to 32A. This was done after an incident in Toronto where someone had a NEMA14-50 on a 40A

Actually, there was not a change to Gen 1 UMCs for Canada. Tesla released a new 14-50 adapter for Gen1 that limits the UMC to 32 Amps. It was included with Canadian cars for exactly the incident you mentioned, and subsequent requirement by Toronto authorities. IIRC, Tesla still provided, for a few months at least, 40 A adapters to Canadian Providences that did not require the 32 A version.

I bought the Canadian 32 A UMC adapter to complement the 40 A adapter that came with my US-spec model S. I tested both on a 50 A circuit and they both limit ampacity per spec.

I now have adapters for every available ampacity: 15, 20, 30, 40, and 50 A so that I can plug into any North American outlet (with homemade adapter where required) and have a hardware limit to 80% of the circuit breaker value. I bought them for destination charging use.

GSP
 

Dan Baldwin

Member
Jul 2, 2018
226
173
Boulder Co
I am really getting tired of using my brakes so much this winter. I hope the aggressive regen hobbling will be addressed soon. I have tested and can say that scheduled departure does not warm the battery.... why not ?
 
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tyler2323

Banned
Dec 2, 2019
426
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NV AZ CA
Holy word wall Batman!

I'll see if I can address some of this continued misinformation presented as fact by someone who briefly scanned over a few posts in internet forums about this topic once and now considers himself an expert.



That's not what I said so stop putting words in my mouth to try to make your point.

What I said was the gen 1 was analog components and the gen 2 version was digital. The digital component gen 2 version IS an upgrade over the gen 1. It's also less expensive to make which is the case for most every device that made the transition from analog to digital circuitry.

You keep trying to make it seem like gen 1 UMCs were burning houses down left and right and the truth is it never happened. The few times that outlets/plugs melted or got hot ended up being a problem with the outlet installation causing the problem in every instance I saw.

Also, for a self-professed expert on this topic I'm surprised you don't know that the "C" in UMC and HPWC stands for "Connector" and not "Charger" as you keep referring to them. Probably nit picking but it's a pretty glaring mistake for someone who knows everything. I bet you knew that though. Probably just testing me.



The first portion of this is accurate and almost a copy/paste from what I said. Good job!

The second half it comes off of the rails though with your stories of how much harder it is on the charger or car to run accessory type features of the car while it's plugged in. That's just dumb.

If you knew the first thing about electricity and these chargers you would know that 40A @ 240-volts is 40A @ 240-volts and absolutely no amount of items running in the car, the house, your neighbors or whatever changes that. Zero. Saying "obviously" in things like you have some idea what you're talking about doesn't help. You're wrong. Period.



Yes, 32 is 80% of 40 so you aren't entirely wrong. Another gold star!

Now, as to why they arrived at 32A it wasn't just a guess or a dart on a dart board regardless of what you "assume".
Gen 2 UMCs are 32A because of the fact that some NEMA 14-50 outlets installed decades ago all over the country are wired only for 40A due to a previous stance on what the NEMA 14-50 standard was. As you're traveling around the countryside you may find a NEMA 14-50 on a 40A circuit and if you don't know what to look for. Connecting a Gen 1 UMC capable of 40A into a 40A circuit could create an unsafe condition much in the same way that connecting a Gen 2 UMC capable of 32A into a 30A outlet could in the hands of a moron. In both situations you're relying on the fail-safes to do their job and those aren't 100% so it's best to avoid those entirely through common sense.

The decision was made to go with a 32A continuous charger as it made the most sense. It also matched the majority of cars being manufactured at the time which also had less expensive AC chargers in them.... all in an effort to cut costs. Users who wanted higher charge rates would upgrade the onboard AC charger and likely install HPWC making for more profit... again financial decision in so many ways.

You keep saying it had nothing to do with cost but I see a bit of a pattern emerging here if you take your head out of the sand.



I clearly have done my research and the accusation that I haven't only makes you look that much more foolish. I also have paid special attention to owner posts over the years here and at many, many other places online and in person.
The Gen 1 issue was the problem with the adapters and NOT the UMC itself. This is why they recalled all of the adapters for a few of the different outlets: NEMA 14-30, NEMA 10-30 and NEMA 6-50 with the black base. None of the others were involved in the recall because they were perfectly safe when matched to outlets/circuits that were properly installed to code. The "fires" and issues you speak of were directly related to the first version of these three adapters and revision 2 of those fixed that. No more issues. Even the frequency of those "issues" has been greatly exaggerated as there were only two of these reported prior to the voluntary recall of these three adapters that weren't adapters included with the UMC.

I never said that a Gen 1 UMC can't lead to fires but so can the Gen 2. To make it sound like it's more of an issue or that the Gen 1 UMC is somehow a widow maker is simply wrong. No other way to explain that. In most of the issues where someone's plug melted it was actually the home's wiring that was the culprit. In almost every case I've seen of overheated plugs (gen 1 or gen 2) the outlet is the problem with the wiring (not proper size) being 2nd most frequent. In that instance it doesn't matter if you use a gen 1 or a gen 2 if the wiring is done improperly.

Often times it's a homeowner that throws a NEMA 14-50 in and does the proper break, wire and all components are to code but the installation is done improperly. In these instances, you will see that the wire isn't stripped completely of insulation so when they tighten the outlet's lug down on the wire a little tiny strip of it gets caught in the contacts. This will create resistance at that point in the circuit and if you know anything about electricity (I assume you don't based on some of the things you've said so far so) resistance equals increased heat. Heat in and of itself isn't bad but there's a limit to what is considered excessive and excessive heat can be dangerous.

In just about every case I've seen of melted or overheated outlets the home owner's wiring was to blame. This same thing can happen with a Gen 2 although the potential for failure would be 20% less based on the sustained draw difference. Again, we're talking about rate of failures due to improper wiring so the issue STILL Isn't the UMC.
That doesn't mean it's not possible nor did I say it wasn't. These items are man-made and men make mistakes. I'm just not buying your claim that gen 1 UMCs are death traps and the UMC gen 2 is flawless and that was the motivation behind the update because I know better.

This is largely conjecture an assuming to know what most of the failures are since I haven't seen ALL failures first-hand but if you can assume based on zero information why can't I assume based on some information?



Just because someone had something happen to them doesn't mean the know the first thing about why it happened. Experiencing a problem doesn't make you an expert. I don't have to burn a house down due to faulty electrical work to know how to prevent it. Likewise, a homeowner can have their house burn the ground due to improperly electrical work and still not know the first reason why.

Homemade adapters can be used for BOTH gen 1 and gen 2 so this entire portion is wrong. Again, if you knew half as much as you claimed you would already know that. Most people use NEMA 14-50 adapters supplied by Tesla for their homemade adapters which allows for 50A. They then manually decrease the amps in the car via the MCU to match whatever outlet they're plugged in to. If you don't do this you can cause a potentially unsafe condition in BOTH the Gen 1 and Gen 2. In your "photographic proof" of how "dangerous" the Gen 1 UMC is this could have just as easily been done with a Gen 2 UMC.

In fact, the car pictured in your "mic drop pic" happens to be a Model 3 if you look a the background. Gen 1 UMCs never came with the Model 3 so odds are pretty good that your picture actually proves my points that Gen 1 and Gen 2 possess equal potential for danger in the wrong hands and also that you have no idea what you're talking about. You're trying awfully hard to prove how much more dangerous Gen 1 UMCs are than Gen 2 UMCs to support your stance but it's just not the case.

I covered homemade adapters earlier in my post that some people create their own adapter kit to cover more uncommon outlets and most that go to that effort either 1) know what they're doing or 2) learn what it is they're doing because they understand the dangers of not knowing when you effectively remove/bypass safety features that the manufacturer put in. The idiot who knows not what he's doing and also doesn't take the time to educate himself on what he's doing and STILL bypasses safety features will is practicing a dangerous game that could end in burning himself, his car and house to the ground.

This is the same between Gen 1 and Gen 2 so saying otherwise is just more proof you're clueless. The most accurate things you've said are just paraphrasing things I already said.

You should just quit while you're behind. Every post you make you dig your hole deeper. I'd resist the urge to try to lash out and save face because you're only making things worse by supplying even more misinformation as fact.


First off the Gen 2 is called Gen 2 MC not UMC if you want to get into details. Referring to them as a charger is simply stating what they are, “car chargers.” If you want to keep the reference to connector since that’s what Tesla refers to them with the MC and UMC (Mobile Connector and Universal Mobile Connector) than you can but ultimately the MC in its entirety is a mobile charger and HPWC (HIgh Powered Wall Connectors) is a Destination Charger. So we don’t refer to Superchargers as Superconnectors. So really the connector that you are referring to would be the Main Unit. So when I refer to MC in the explanation it’s referring to the Main Unit, as I will explain in more detail how the MC and it’s adapters talk to each other and the MC aka Main Unit it was tells the car how much power to draw.

Nothing you posted explained the difference between the two or how they each work. So copying and pasting from your post that had no information regarding the working components of each charger is a humorous claim. Saying one is digital and the other analog is a laughable explanation. Basically explains that you don’t know anything about how they work and would be an F if that was your answer if asked to explain the differences between the 2 on a test lol

The Gen 1 UMC Charger is only capable of reading the amount of power to draw from the outlet. That’s it, it does not reduce the power based on the temperature nor does its adapters talk to the MC every second like the Gen 2 chargers. The Gen 1 chargers adapters have only a resistor, while the Gen 2 chargers have a circuit board/chip in the Gen 2 adapters and MC do a lot more than just read the power it supplies based on the outlet. I see nowhere in your post where you describe that the Gen 1 UMC adapters have resistors and the Gen 2 MC (Not UMC) has a circuit board.
So simply stating one is analog the other digital just shows you have no clue how the components work. You should probably write this down or copy and paste it cuz u just keep digging a bigger hole.
Just to make it 3rd grade level easy we will use pictures to help you comprehend.
Here is what a Gen 1 UMC looks like, 1 lone resistor. Doesn’t look too advanced does it.

D9FED601-7CEC-4A87-9DA1-61DE5AA7BF43.jpeg


Now let’s look at the technology of the Gen 2 “MC” adapters
4833D49D-3957-41D8-A4F2-14395F6126E1.jpeg
373AD6D6-E97C-49F3-ADB8-ECE4C1115AA8.jpeg


Third assuming the person is using a Gen 2 MC because they have a Model 3 is extremely dumb since many owners with Gen 2 chargers have bought Gen 1 just because they want the extra amps it provides. Especially if they owned a Tesla previously that came with a Gen 1 UMC.

The claim that anyone is using a homemade adapter is hilarious cause no one is making their own adapters. They are readily for sale.

The claim Gen 2 chargers are much safer isn’t a claim it’s a fact since the Gen 2 components that it’s equipped with will drop the voltage if the cable becomes too hot, something Gen 1 UMC will not do! Or they will completely shut off cause what usually is the leading cause of a fire? Answer: Too much Heat
So saying it isn’t safer means you still have no clue the difference between the 2 chargers.
Let’s go into more detail.
The example of connecting a Gen 2 MC into a 30 amp outlet is not relevant since the Gen 2 MC will only allow 24amps.
Connecting a Gen 1 UMC into a 40 amp outlet will not read the voltage/amps and can charge to 40 amps. Since you are an electrician you should understand this and I left a picture just so it makes sense for you. I assume you should understand how this works if not I can explain in more detail for you once again.

0D63739B-2278-43B2-BDA5-021A6335B686.jpeg


Lastly let me include a post from someone who has had extensive experience with both these charges or connectors lol

EC2BCCCE-FD4B-4F3C-B199-E087A72A8215.png


Now if you just took 2 min to search this forum you will see endless amounts of Gen 1 chargers melting etc.

But yea please keep digging that whole and if you want me to breakdown the 40amp example please do tell. Since it’s code I would think you should know but than again you’re too busy copying and pasting
 
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