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Vitals: What do those temperature bars mean?

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My apologies. I know that this has been discussed (Scott?), but I can't find the topic anywhere. I've searched by title, author, and scrolled through pages of threads. Well, here goes:

What are the real-world temperature ranges that correspond to the bars (blue/yellow/red) on the Vitals screen?

My battery never drops to the lowest blue bar, but I assume that exists to indicate freezing temperatures since the battery would automatically be heated in that event. My Motor and PEM always start out at the lowest blue bar, but the PEM quickly heats up to maybe the third blue bar. The Motor rarely even gets as hot as the PEM.

I've never seen a yellow bar, although I have seen Performance turn red.

Anyway, I'd like to correlate my Mac log graphing app displays with what I see on my Vitals screen. Any help or links would be appreciated. Maybe this topic can serve as a focal point for temperature discussions if the existing discussions are in the midst of broader topics.
 
Specifically. From white vs. red...

attachment.php?attachmentid=986&d=1282721159.png
 
Thanks, Scott.

I assume that the second 3.4.15 should actually be 3.4.16

Considering that we're now on firmware 4.6.3, is it possible that the temperature bar thresholds have changed yet again?

P.S. I also assume that the actual thresholds are in Celsius, not Fahrenheit. Are the temperature sensors all reporting Kelvin? ... or do some of the temperature sensors report values in different units than others? I've done some research into temperature sensor chips, and I've learned that there are varying units as well as wildly varying accuracies.
 
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Thanks, Scott.

I assume that the second 3.4.15 should actually be 3.4.16
no it's labeled correctly as 3.4.15. The first chart shows the range the second just the lowest temp that the bar comes on.

Considering that we're now on firmware 4.6.3, is it possible that the temperature bar thresholds have changed yet again?
This was for my R1.5. I'm currently on 3.5.18 so it probably hasn't changed. I looked at 2.x and saw it was the same, but I don't remember the version. The 2.x can print the temp next to the bar in debug text mode, the 1.5 cannot so it has to be done manually.
P.S. I also assume that the actual thresholds are in Celsius, not Fahrenheit. Are the temperature sensors all reporting Kelvin? ... or do some of the temperature sensors report values in different units than others? I've done some research into temperature sensor chips, and I've learned that there are varying units as well as wildly varying accuracies.
On the CAN bus it's all in Celsius.
 
Specifically. From white vs. red...

attachment.php?attachmentid=986&d=1282721159.png

Neat to see those numbers, thanks. Shows how the 'happy' range doesn't really line up between any of the 3 systems.

I wonder how the liquid-cooling system in the Model S will take this into account, or specifically, how much they will have to separately 'plumb' the cooling systems between the 3 components? Also shows how you'd have to account for thermal issues when bolting the PEM directly to the motor in the new drivetrain configuration (temperature soak from motor to PEM) Neither of these are show-stoppers obviously, just interesting engineering challenges...
 
Neat to see those numbers, thanks. Shows how the 'happy' range doesn't really line up between any of the 3 systems.

I wonder how the liquid-cooling system in the Model S will take this into account, or specifically, how much they will have to separately 'plumb' the cooling systems between the 3 components? Also shows how you'd have to account for thermal issues when bolting the PEM directly to the motor in the new drivetrain configuration (temperature soak from motor to PEM) Neither of these are show-stoppers obviously, just interesting engineering challenges...

Probably the simplest thing would be to have one loop, with the coolest things at the beginning of the loop and hottest things at the end. Even if that means something has to run cooler than absolutely needed, it won't hurt anything and may actually improve durability. Worst-case it might result in having to pump more heat out of the system than would otherwise be necessary.
 
From back at the Model S unveiling, JB told me the motor and PEM would share the same cooling loop. I've always understood this to mean the battery pack cooling would remain separate.

That sounds like a very sensible compromise. You want the battery pack to be as cool as possible, so you don't want to load its cooling loop with other heat sources.

For electronics, as long as you keep them about 30C below their rated temperature limit there's no significant impact on lifetime. Typical maximum junction temperature (meaning the silicon itself) is +125C for automotive devices, so 95C is usually the maximum operating temperature you want to see. The motor could of course run much hotter without damage.
 
My Roadster was recently in the shop for a replacement of the Alpine unit's Bluetooth module. After I got the car back the temperature display showed the temperature in numbers:
tesla temp.png


I asked at Tesla and they do not know how this got there! At the next service the PEM was cleaned and the temperature screen reverted to the bars only. How can I can the temperature readout back? Any ideas other than look at my OVMS????
 
My Roadster was recently in the shop for a replacement of the Alpine unit's Bluetooth module. After I got the car back the temperature display showed the temperature in numbers.

They had put your VDS in 'diagnostic messages' mode.

Presumably they turned off that mode at your subsequent service.

Side-effect of turning on that mode is that you also get bothered with not-important VMS error codes (and some of the important ones are less meaningful). I would suggest you leave it off and use OVMS if you want the real temperatures.

Regards, Mark.
 
My Roadster was recently in the shop for a replacement of the Alpine unit's Bluetooth module. After I got the car back the temperature display showed the temperature in numbers:

I asked at Tesla and they do not know how this got there! At the next service the PEM was cleaned and the temperature screen reverted to the bars only. How can I can the temperature readout back? Any ideas other than look at my OVMS????

This is turned on debugging while they were in the Diagnostics screen (Its in the VDS and temps are shown with the 2.x's, not 1.5's when in this mode). Its actually called "User Debug". It won't hurt but it will be verbose on errors, some that really don't mean anything bad but just for logging that help's the tech's out. With that you get the real temperature reading in C degrees as you've posted above. It doesn't hurt anything, actually really useful. But when its in this mode you don't want to wig out that for every alert you get thinking your Roadster is about to die from all these messages popping up that you have to dismiss. However when a real issue does occur, you get about 3 or 4 messages. It will say "Debug" in the message by the way. These messages, when used properly, do help the Technician in better diagnosing the issue. If you take it back to Tesla they'll turn off "User Debug" for you within a matter of minutes.
 
This is exactly what happened. Incidentally my PEM was super clogged up form New England leaves and spring buds. The alert that came up for the high PEM temperatures was something I had not seen before and in fact neither the service center nor the tech at Tesla headquarters knew what the error message was - that is probably why.

I don't think they turned off the User Debug mode on purpose after the PEM cleaning - I think it cleared on its own after they re-attached the battery.

I find the techs and service guys do not know Roadster anymore like they used to - all new service guys. In our area there are hundreds of Model S but only 2 Roadsters I know if so they do not see us much.

Thanks for the note.
 
This is exactly what happened. Incidentally my PEM was super clogged up form New England leaves and spring buds. The alert that came up for the high PEM temperatures was something I had not seen before and in fact neither the service center nor the tech at Tesla headquarters knew what the error message was - that is probably why.

I don't think they turned off the User Debug mode on purpose after the PEM cleaning - I think it cleared on its own after they re-attached the battery.

I find the techs and service guys do not know Roadster anymore like they used to - all new service guys. In our area there are hundreds of Model S but only 2 Roadsters I know if so they do not see us much.

Thanks for the note.

You may want to ask about the winter/snow dam upgrade. I've heard that will help with the 2.x PEMS from getting filled with junk like leaves and crud much better. They may have turned on user debug in order to verify on their test drive that they correctly solved the problem you reported of the PEM overheating by just a simple cleaning. Makes sense to me and the proper way to diagnose and attack the problem.
 
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They turned it on when they replaced my Bluetooth module. They turned it off (or it reset when power was disconnected) when they cleaned the PEM a month later.

I have the winter/snow dam upgrade but it still got clogged. I need to clean the PEM twice a year - late fall and late spring.
 
The P.E.M. in my 13,000 mile 2.0 always seems to be on the third temperature bar, even when I first pull out of the garage. Granted, it's been warm here in Southern California, but even when my garage is in the low 70s (21C) the P.E.M. temperature only intermittently flirts with the second bar. Is this normal? I notice what sounds like failing bearings in some fan(s) in the battery/P.E.M. area. Given what I've read here about P.E.M. thermal management issues, I'm concerned. My next annual service will be 31 days from now so I will probably ask about it at that point but would still be interested in comparing this with other owners' experiences.
 
The P.E.M. in my 13,000 mile 2.0 always seems to be on the third temperature bar, even when I first pull out of the garage. Granted, it's been warm here in Southern California, but even when my garage is in the low 70s (21C) the P.E.M. temperature only intermittently flirts with the second bar. Is this normal? I notice what sounds like failing bearings in some fan(s) in the battery/P.E.M. area. Given what I've read here about P.E.M. thermal management issues, I'm concerned. My next annual service will be 31 days from now so I will probably ask about it at that point but would still be interested in comparing this with other owners' experiences.
The third bar is normal, especially in warm weather. The "failing bearings" sound is not normal and is often the sign of a fan motor on its way out. This was common with the early 2.x fans because the bearings were not sealed very well. It's not common with the replacement fans that have better bearings and seals. The newer fans also have the motor in the center where it's a little more protected from dust (but only a little).
 
The third bar is normal, especially in warm weather. The "failing bearings" sound is not normal and is often the sign of a fan motor on its way out. This was common with the early 2.x fans because the bearings were not sealed very well. It's not common with the replacement fans that have better bearings and seals. The newer fans also have the motor in the center where it's a little more protected from dust (but only a little).

I tried to record what it sounds like. This is just a few moments after it starts charging. After that, more fans activate and they kind of drown out the noise at issue (which you might hear just in the last second or two of the video).

https://photos.app.goo.gl/DRVpoV1t7W2kbg9J3

Is fan replacement something the SC does, or are they going to tell me I need a new P.E.M.?
 
Is fan replacement something the SC does, or are they going to tell me I need a new P.E.M.?

Service centers can and do replace PEM/Motor fans and assemblies independently of the PEM/Motor. Also, it would be a good time to check the fan connector to the PEM, or have the service center technician take a picture. Look for signs of heat such as dilation or browning around the pin inputs on the receptacle side.
 
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