[krheinwald]

Are you sure? Is there a Polestar Transformer schematic you have seen?

There is not a single transformer. There are 3 identical modules - either each one connected to its own phase, or all 3 conencted in parallel.
This is also supported by the effect that this bug aleays reduces the charging rate by 1/3.

While I don't have the PS specific schematics, here is a general one:

The difference to the PS is that we have 3* 3.6kW modules and that the 1/3P switching is dynamic, not static.

 

[GDank]

There is not a songle transformer. There are 3 identical modules - either each one connected to its own phase, or all 3 conencted in parallel.

While I don't have the PS specific schematics, here is a general one:
View attachment 9002

Thanks, I've seen other schematics where each transformer is switched in depending on the input.
Below is an example of how they work on both 1P and 3P operation. In the US they may combine as shown in your example, as it's all 1P up to 48A.

 

[krheinwald]

In the US they may combine as shown in your example, as it's all 1P up to 48A.

Which is basically identical to my schema, except for the 3rd phase not being switched.

Do you really think they put in different modules for the different markets?

The charging rate always being reduced by 1/3 by this bug in every market seems to indicate otherwise.

 

[GDank]

Do you really think they put in different modules for the different markets?

The charging rate always being reduced by 1/3 by this bug in every market seems to indicate otherwise.

Well they put different plug sockets in for different markets. But yes I'd agree normally one module world wide would make more sense financially.

Although 5kW isn't 2/3rd's of 7.2kW ... it's 70% and 26A out of 32A is 80%. Hence why I don't think it's a module down issue's.

It's defiantly an odd bug.

 

[whiteco3]

Mine charges at 20/32A on the 7KW 1P . If I dial down the amps to 26 I can coax it up to charging at 25A, but the minute I dial it up towards 32A it drops back to 20A

 

[GDank]

Mine charges at 20/32A on the 7KW 1P . If I dial down the amps to 26 I can coax it up to charging at 25A, but the minute I dial it up towards 32A it drops back to 20A

Is that on timed or just any time charge?

Very strange behaviour.

 

[whiteco3]

Is that on timed or just any time charge?

Very strange behaviour.

That's on either. It does seem to be intermittent but can happen on both timed/untimed charges. I'd say it happens on less than 25% of charges, but I can't figure out any pattern or what triggers it.

 

[stevelup]

Since 1.7, mine is regularly only drawing 5.9kW instead of 7.2kW. It's frustrating because I can no longer fully recover my daily commute energy use in my Octopus Go charging window.

For single phase 32A, the car either uses two chargers at 3.6kW each to do 7.2kW or it runs all three chargers at 2.4kW... We have no way of knowing which it is.

Nothing explains drawing 5.9kW though - it's such a random number and no obvious multiple. I don't understand where that number is coming from - it really doesn't make sense other than it being a really stupid software bug.

The fault is intermittent - I can't detect any pattern.

And yes, I may be contributing to the problem, but there's no way I can be arsed booking into the dealer for this when it's an obvious software bug - they are clearly not going to be able to do anything about it.

 

[polerad]

I only have single phase AC charging available. I don't have any timers set. I sometimes get the full set amps (40A, usually), and sometimes get 2/3 or even 1/3 that setting. This bug preceded v1.7 and I think came with v1.6 ( denoted 213x at the time.) It occurs randomly and without a particular pattern and independently between both cars - when one is affected the other could be also affected or unaffected. The last time I had the bug was on Nov 15 it charged at 6kW instead of the usual 9kW.
Resetting the car or the EVSE doesn't fix it. I have seen it resolve itself mid-charge, going from 2/3 amp setting to full, with an audible click coming from the EVSE.

I can't hack it by, e.g. bumping the setting up to 48A to then get 2/3 * 48A= 32A. The draw stubbornly stays at 2/3*40A= 26-27A. But if I drop the amp rating, the draw drops according to 2/3*setting (or 1/3 when it decides to do that).

I believe this is definitely a bug of the car, not the EVSE. I believe the car says "give me X amps" the EVSE says "I'll give you min(X, my_max_amps)". Then the car pulls Y=1/3, 2/3, or 3/3 out of its hatch and draws Y*min(X,my_max_amps) - al least for single phase. In light of @stevelup 's bug I wonder if the 3 phase bug behavior is a bit more complex as his 5.9kW is noticeably similar to my 6kW = 2/3* 9kW single phase charging bug.

 

[Tann_man]

There are people here that know a lot more than me on this subject. I’ve noticed from my last car which used to pull about 8kw, the P2 pulls between 7.3-7.5kw according to my smart charger. When I first got the car I set it to 32amps and have kept it there. The estimated ‘miles per hour’ was 21. Now seems to be estimating 17 when I plugged it in just now. Maybe the ‘miles per hour’ could be an estimate based on your efficiency? Been doing a few short journeys in the cold 🤷🏻‍♂️ The kW has never dropped. Also people on Octopus go, have you not thought about Octopus go ‘faster’?

 

[mxs]

Wow … is there anyone who actually charges consistently at 32A or more? Seems like everyone’s has been up and down. Clearly must be some software bug. These bugs are the only reason which still makes me a fence sitter as far as this car goes.

 

[Mick]

I charge at 48A and nearly always pull 11kW, but I can remember 3 times that I checked the charge graph the next morning and it only charged at 7.4 kW. Like @polerad I first saw this after the OTA prior to 1.7 and I've seen it once after 1.7. The last several charges have been at full speed so it hasn't caused me problems. I will say I must have a Tuesday car or something as I have had remarkably few problems with it. Never had it in for any service/repairs and all updates have been OTA. The few times I've had a connectivity problem or the bad AVAS speaker issue, it has gone away either with a reboot or sitting overnight. I will take it to get the speaker replaced at some point, but I only had the issue for one day and then it must have dried out.

So anyway, I'll keep an eye on my charging sessions, but I think it's a pretty rare issue for me.

 

[Dark-Fx]

Wow … is there anyone who actually charges consistently at 32A or more? Seems like everyone’s has been up and down. Clearly must be some software bug. These bugs are the only reason which still makes me a fence sitter as far as this car goes.

I only had the one day where it was acting weird. Hasn't done it since. Car happily sat at 39/40A for 8 hours the other day, from 7% to 90%. I'm putting in a 48A charger right now.

 

[StarPole]

I believe this is definitely a bug of the car, not the EVSE. I believe the car says "give me X amps" the EVSE says "I'll give you min(X, my_max_amps)". Then the car pulls Y=1/3, 2/3, or 3/3 out of its hatch and draws Y*min(X,my_max_amps) - al least for single phase. In light of @stevelup 's bug I wonder if the 3 phase bug behavior is a bit more complex as his 5.9kW is noticeably similar to my 6kW = 2/3* 9kW single phase charging bug.

My experience with this bug is different than yours. I had this happen a day or two after the P1.7 OTA, but I was able to resolve it by unplugging and restarting my EVSE (OpenEVSE). Nothing I changed in the car (amp settings, infotainment resets, long sleeps, etc) fixed it, but after I completely powered down the EVSE it started behaving normally again.

I wonder if the car is misinterpreting the power signal from the EVSE after the last update, and therefore not taking the full current even when available.

According to the SAE J1772 Wikipedia page:
Control Pilot (Current limit): The charging station can use the wave signal to describe the maximum current that is available via the charging station with the help of pulse width modulation: a 16% PWM is a 10 A maximum, a 25% PWM is a 16 A maximum, a 50% PWM is a 32 A maximum and a 90% PWM flags a fast charge option.[27]

The PWM duty cycle of the 1 kHz CP signal indicates the maximum allowed mains current. According to the SAE it includes socket outlet, cable and vehicle inlet. In the US, the definition of the ampacity (ampere capacity, or current capacity) is split for continuous and short term operation.[27] The SAE defines the ampacity value to be derived by a formula based on the 1 ms full cycle (of the 1 kHz signal) with the maximum continuous ampere rating being 0.6 A per 10 µs up to 850 µs (with the lowest 100 µs × 0.6 A = 6 A). Above 850 µs, the formula requires subtraction of 640 µs and multiplying the difference by 2.5. For example (960 µs − 640 µs) × 2.5 A = 80 A.[26]

So maybe something about the update causes the car some confusion about the signal wave, and resetting the EVSE generates a new wave/signal that the car can then interpret appropriately.

 

[Dark-Fx]

My experience with this bug is different than yours. I had this happen a day or two after the P1.7 OTA, but I was able to resolve it by unplugging and restarting my EVSE (OpenEVSE). Nothing I changed in the car (amp settings, infotainment resets, long sleeps, etc) fixed it, but after I completely powered down the EVSE it started behaving normally again.

I wonder if the car is misinterpreting the power signal from the EVSE after the last update, and therefore not taking the full current even when available.

According to the SAE J1772 Wikipedia page:
Control Pilot (Current limit): The charging station can use the wave signal to describe the maximum current that is available via the charging station with the help of pulse width modulation: a 16% PWM is a 10 A maximum, a 25% PWM is a 16 A maximum, a 50% PWM is a 32 A maximum and a 90% PWM flags a fast charge option.[27]

The PWM duty cycle of the 1 kHz CP signal indicates the maximum allowed mains current. According to the SAE it includes socket outlet, cable and vehicle inlet. In the US, the definition of the ampacity (ampere capacity, or current capacity) is split for continuous and short term operation.[27] The SAE defines the ampacity value to be derived by a formula based on the 1 ms full cycle (of the 1 kHz signal) with the maximum continuous ampere rating being 0.6 A per 10 µs up to 850 µs (with the lowest 100 µs × 0.6 A = 6 A). Above 850 µs, the formula requires subtraction of 640 µs and multiplying the difference by 2.5. For example (960 µs − 640 µs) × 2.5 A = 80 A.[26]

So maybe something about the update causes the car some confusion about the signal wave, and resetting the EVSE generates a new wave/signal that the car can then interpret appropriately.

I tried all that and I still had the same issues. Your reset might have just been enough time for the system in the car to fix itself. If it happens to me again, I'm going to pull all the covers off and take some shots of the charging unit with my thermographic camera.

 

[StarPole]

I tried all that and I still had the same issues. Your reset might have just been enough time for the system in the car to fix itself. If it happens to me again, I'm going to pull all the covers off and take some shots of the charging unit with my thermographic camera.

It was literally fixed as soon as I restarted my EVSE, but YMMV. It likely has multiple etiologies—some on the car side and some on the EVSE side.

 

[polerad]

My experience with this bug is different than yours. I had this happen a day or two after the P1.7 OTA, but I was able to resolve it by unplugging and restarting my EVSE (OpenEVSE). Nothing I changed in the car (amp settings, infotainment resets, long sleeps, etc) fixed it, but after I completely powered down the EVSE it started behaving normally again.

I wonder if the car is misinterpreting the power signal from the EVSE after the last update, and therefore not taking the full current even when available.

According to the SAE J1772 Wikipedia page:
Control Pilot (Current limit): The charging station can use the wave signal to describe the maximum current that is available via the charging station with the help of pulse width modulation: a 16% PWM is a 10 A maximum, a 25% PWM is a 16 A maximum, a 50% PWM is a 32 A maximum and a 90% PWM flags a fast charge option.[27]

The PWM duty cycle of the 1 kHz CP signal indicates the maximum allowed mains current. According to the SAE it includes socket outlet, cable and vehicle inlet. In the US, the definition of the ampacity (ampere capacity, or current capacity) is split for continuous and short term operation.[27] The SAE defines the ampacity value to be derived by a formula based on the 1 ms full cycle (of the 1 kHz signal) with the maximum continuous ampere rating being 0.6 A per 10 µs up to 850 µs (with the lowest 100 µs × 0.6 A = 6 A). Above 850 µs, the formula requires subtraction of 640 µs and multiplying the difference by 2.5. For example (960 µs − 640 µs) × 2.5 A = 80 A.[26]

So maybe something about the update causes the car some confusion about the signal wave, and resetting the EVSE generates a new wave/signal that the car can then interpret appropriately.

Interesting!
Any thoughts on why it seems to set to 1/3 or 2/3 of the indicated amps?

The update that made the bug for me was the one (IIRC) when the # phases started showing in the charging status screen. So I had speculated it was related to that measurement messing things up.

 

[julianm]

I noticed mine reverting to 26A after P2124.

Just bumping mine from earlier in the thread. Issue started with P2124, CS told me it’d be fixed with P2130 (it was not), then P1.7 (it was not).

I pretty rarely pull the full 40A my EVSE will do. Like others, I’ve tried restarting a lot of different things to correct the issue. In my case, if I restart the EVSE, I will pull 40A for ~10-30 min, then it’ll degrade to 26A. No other restarts seem to impact it.

 

[GDank]

It was literally fixed as soon as I restarted my EVSE, but YMMV. It likely has multiple etiologies—some on the car side and some on the EVSE side.

But this is happening over multiple countries and multiple different charging units.

So seems more the car than a charger issue.

Just because this worked for you may have a coincidence and your car was fine but charger was not.

 

[whiteco3]

but there's no way I can be arsed booking into the dealer for this when it's an obvious software bug

I told Polestar CS the same and asked them to at least try and get a response from 'technical' that this is a recognised issue that they are aware of, affecting multiple owners, and their likely timeline to fix it. I'm not hopeful of any coherent reply but, if I do, I'll share.