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Scheduled charging restricted to 16A

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There have been enough reports of this that I wonder if it is a software bug ...
... alternatively the huge influx of M3 in UK might be generating significant numbers of "real" scenarios.

Similarly more "tripped the whole house" reports, where a single device being unplugged then fixed the problem - so very slight earth leakage or somesuch, exacerbated when car was charging. My M3 did that at a friend's house, ran an extension over to their neighbours and no problem there.

If it were me I would most definitely want to find-and-fix the culprit for fear that it might otherwise lead to a proper disaster.

I have not been following other country forums, is this a recurring problem in other parts of the world or just UK? Might be a software bug specific to UK specific conditions. I do't remember hearing of it on MS/MX ... but far few numbers of those cars of course

So, personally, I would most definitely not be forcing the charge higher in case there is a real issue in the house wiring. (well, I'm a software bod, so i would definitely first do the "Lets see if it will do it again" test ...)

I don't know how feasible it is in practice, but for overnight charging might be worth turning off all circuits that are not needed over night - so just leaving bedroom circuit - and seeing if that makes any difference ... if it stays at max AMPs then likely to be a fault on one of the isolated circuits.

Other threads here have said that it was necessary to physically unplug a turned-off device to isolate the [whole house tripping] problem, so devices just being OFF may not be sufficient.



Normal for Tesla. "Chuck it out there" software development policy. Seen this plenty of times over the last 4 years, within a month or two it is improved / fixed and then users have short memories / quick forgiveness. I think it is a crap way of doing development, but maybe there is some upside I haven't considered ... e.g. additional feedback from irate! users which is, also, taken into account
The reason why I think this is a software bug is that every manually started charge does 32A no problem.
I only have the 16A issue when the car was sleeping and a scheduled charge is started.
The house is 2 years old, the BMW i3 charges just fine and there has never been even the slightest glitch with breakers and RCDs.
 
I think this is a software bug is that every manually started charge does 32A no problem.

Good point, hadn't considered that; it does indeed point to that.

BMW i3 charges just fine

I haven't heard of this with any MS / MX which may strengthen "M3 Software bug". But that might be because number of MS/MX is small, compared to M3

If specific to UK 13AMP ring-main etc. that might not bode well for a quick fix. Anywhere else in the world got the same household wiring that we have?
 
Good idea. Sequence for tonight will be:

Teslafi wake up: 0025
Zappi start boost: 0030
Teslafi stop charge: 0035
Teslafi start charge: 0040
Zappi stop boost: 0430

Maybe the Teslafi wake-up will be enough to let the Zappi ramp up to 32A when it comes on at 0030 - in which case the stop-start won't be needed. I'll let it run for a few nights and report back

Did I miss something? This is just to charge a high end, mainstream EV, right?! What are the rest of UK users doing?

It's crazy that such a basic issue as not reliably charging at the correct power appears to be so prevalent. I am in a rural location but do not have any issues with EV's not charging at full 7.5kw. Given that in the UK you are likely to have a 100a supply, and you should be able to load that with a couple of ovens, lighting, fan heaters, TV's, computers, may be some power tools / machinery as well as charging a car at 7.5kw, overnight charging really should not present a problem. During off-peak I typically run a heat pump, charge two large battery storage systems and charge a car at 7.5kw and have not had a problem.

Normally, your car charger should run off its own distribution board with a suitable earth leakage detector, or at least off a dedicated 32a or 40a circuit breaker in the main board. I think some charge devices now have their own earth leakage trips built in, but I don't know how that works if your distribution box already has earth leakage trip.

A question - not directly related to the OP but since you are all focussed on charging behaviour.

Does anyone know how M3 &/or MS behave if plugged in to a powered-off charge outlet? With other EV's, I set up a time switch / contactor to power the type 2 charge outlet on and off, so avoiding reliance on (all the stuf that goes wrong or gets forgotten). I have found even the same year and model of car (non-Tesla) do not behave the same, although individual vehicles are consistent in their behaviour. With some, I have to schedule a one-off charge using the car onboard scheduler timed to start after the charge outlet powers up otherwise the car never wakes up and fails to charge. These cars work fine without scheduling a charge as long as the charge outlet is turned on at the time when I connect the car. My guess is that this is to deal with power cuts so that once the car has started charging successfully, it will also resume automatically if the power is interupted.

So, how do MS & M3 deal with charging if there is a power cut during a charging cycle?
How do they behave if plugged into a charge outlet that is initially off and powers up a while later?

Thanks for any insight.
 
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Did I miss something? This is just to charge a high end, mainstream EV, right?! What are the rest of UK users doing?
Yes, it’s pretty pathetic to have to go to these extremes just to charge your Tesla reliably.

When I had the Nissan Leaf or the Kona electric the charging side of things just worked. Someone needs to tell Elon that this is not rocket science...
 
I have not been following other country forums, is this a recurring problem in other parts of the world or just UK? Might be a software bug specific to UK specific conditions. I do't remember hearing of it on MS/MX ... but far few numbers of those cars of course

I haven't been following other country forums, but the 16A/32A thing is almost certainly specific to the UK, as we are the home of 32A single-phase charging in three-phase Europe: most of the rest of Europe will be on either three-phase or limited to 16A by supply capacity, while USA has the phases permanently bridged so doesn't need whatever dance our cars are doing to support 16A three-phase vs 32A single phase depending what you plug in. This is extremely likely to turn out as a software bug.

The RCD tripping thing is more mysterious as similar RCD arrangements are widespread in Europe; while the USA generally makes less use of RCDs than we do, the tripping levels where they do are generally lower.
 
As a test, maybe those seeing this on a regular basis could reboot their car after last drive of the day? Not sure if MCU (2 button) or full (2 button + brake) is needed - latter covers more bases if you have a bit extra time.

If occurrences go away with this, then that would point to a cumulative software issue. But its all dependent on how frequent this occurs - its only really going to give up some info if low charge is a regular occurrence.

Of course, just because it doesn't change behaviour wont rule out software, but it would point to software if behaviour did change.

I'm seeing (from a number of sources) a number of transient problems solved by a reboot to make me think this is a worthwhile exercise.
 
I've got an SC appointment on the 11th Dec to take a look at this and a faulty rear side light. Will let you know what they say. I have provided lots of info and TeslaFi logs etc. so they should have enough to go on. Will also included the link to this thread as there are many people with the same issue! Anyone know how many of us have this now in UK, or shall I send out a poll to figure that out?

Cheers
 
If you do a poll, can you please add in a UMC blows the RCD option...

Isn't the upshot of that annoyance that it is not a fault of the UMC, but rather the presence of some device(s) leaking current? and thus depends entirely on whether there are devices plugged in that contribute leakage ... or not?

I've had it happen (with Model-3) at one property, not at 2 others. Too small a sample size to draw any conclusion, other than "not the UMC at fault" ... but might be "UMC contributing to then cause a problem that no other car charger fails on"

So I'm not sure it adds any value to a poll in the sense that:

If it has not happened, for someone, that only tells us that they haven't, yet, plugged in at a site where there are devices which have borderline leakage

If someone has had it happen and main breaker has tripped, at multiple sites, that's not evidence of UMC fault either. Just they haven't tried enough sites (OK, provided "Sites" is less than some reasonable number :) )
 

Yup, but those will cause it to trip wherever suitable conditions are found.

I don't see that polling data will tell you anything about that??, only that it has happened to some people, for some people all the places they have tried (but it would be useful to know about that where the number of test locations is large), and for some people not at all (again, would be useful to here if anyone has tired it all-successes or all-failures at a large number of places)

Definitely of interest if someone has tried two UMC cables on separate cars at one/many location(s) and one-tripped and the other didn't
 
I think what would help, to help Tesla to get it fixed, is first for everyone with the problem to report it to Tesla. Tesla support systems should detect that the issue is being repeatedly reported, and thus increase the priority to getting it fixed. Might even garner some feedback if the issue is known, and being worked on.

Perhaps quote a link to this thread so that Tesla has the ability to tie all the support requests together. - this is the link to the first page (to provide consistency)

teslamotorsclub.com/tmc/threads/scheduled-charging-restricted-to-16a.169521/

Similar situations to this have been solved by Social Media and crowd sourced data, and then banging the manufacturers head with it if necessary. I don't have the electrical skill to know what data might be relevant, but I definitely think it would be worth trying to find the common cause. Tesla knows lots about the car's charging activity, but knows nothing about what Brand of Wall Charger folk are using, what type of wiring their house has, and so on.

Maybe TeslaFi could be persuaded to analyse all cars' data to see how many are dropping AMPs during charging, and if there is any pattern (Geography, Model, Temperature, Voltage ... )

I'll have a go at the data elements that might be relevant, but I doubt my thoughts are likely to be comprehensive enough. Some of my thoughts are long-shots, but it would be helpful to consider everything before data collection starts; its always hard to go back to ask recipients to provide more data later and get records updated

Brand of charger / Commando / etc,
How car is connected (Tethered to charger / UMC / 3rd party cable of some sort)
Version of Software and Date of the first time it occurred
Whether it started occurring "from new" or sometime later
If it has been possible to use a different charger, known to not have the problem with other Model-3(s), did the problem happen there?
Or perhaps Has/Has not happened at another charger (no knowledge about other Model-3s on that charger - e.g. Home vs. Work, or public 7kW charger)
Has an isolation test been done (all other circuits in the house disabled during charging)
If TeslaFi/similar is being used to log data then perhaps some analysis of how often is HAS happened and how often NOT happened.

Some questions about the charging circuit (I don't have the skill to know what is relevant, but I'm thinking: is there a difference between something off the main distribution board, and something off a separate distribution board in e.g. a garage? different earthing scenarios?)
 
I have had my car a week now and experienced this a couple of times. I have not used schedule charge each night as after the first time I didn’t want to get caught short again. I thought I’d try again this morning but woke up to 60% rather than the 90% I need for today.

Stopping and immediately restarting sees the charge ramp up to 32a and 7kw so sounds very similar.
 
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Yesterday I had this text from Tesla service, following on from the one they requested last month where I listed all my 16A charging events:

“Good morning, could you please advise if you are experiencing scheduled charging concerns since the latest firmware update of 12th November? Thank you.”

I haven’t had the problem since then, so this would imply that there was a “fix” incorporated into a software update. Is the “firmware update” incorporated within the standard software update, or is it something they can install remotely on an ad-hoc basis?

Even though I’ve had no further problems, I know I’ve read on here that other people have since the last update.
 
What software version did you get on the 12th Roy W.?

my car came with 36.2.1 and I’ve had problems when using both the Tesla implemented schedule (through the car screen) and also the Rolec schedule via their app.