Charging from Solar PV panels: iSmart software repeatedly resets Charging Settings and stops charging prematurely

It is a nightmare for you but as someone who has been on the other side of the fence, i.e. having to write the software and then test it , it is a nightmare for the manufacturer. These systems only work because of the standards that define how they should interoperate but that does not stop tweaks and changes which can make or break a system especially when the system then relies on a slight deviation that gets tidied up without telling anyone else.

When I was with Motorola, we froze all the software that was running on the computers that were used to generate software because just little tweaks from the compiler supplier, Microsoft at al. These changes could mean the difference between something working and not working later. The issue of then having to track this down and fix it was horrendous so we did not allow any updates.

OTA is seen as an advantage but there is an argument of "if it ain't broke don't fix it". The Tesla MG5 charging program is an example of this in that the MG5s used to work but now with a couple of software revisions from TESL, the same cars no longer work. Tesla blame MG... Customers blame MG for not meeting the standards yet the reality is that it is more likely that Tesla changed something in the behaviour which MG did not know how to cope with. If Tesla had not made the changes, there would not be a problem. If MG had a better understanding of what chargers might do outside of the standard, the problem would be solved. Who is to blame?

As for overriding user settings... that will depend on the recovery strategy that is used. I used to reset the user settings if an unexpected error occurred because I did not know if the user setting combination was part of the problem! They might be valid settings but did they cause a chain of events that led to the problem. I could save them but then it would create a loop where the system would not not allow a recovery or opportunity to overwrite the "wrong" settings. When stuff bricks it is often because it is trying to do something in a loop with no escape opportunity.

Its like the display option on a PC - put in the wrong option and the display screws up. If the PC did not reset those display settings using a timeout, they could not be changed back.

As for combinations: Owners have Powerwalls with umpteen software versions, PV controllers from many suppliers with a charging unit from someone else all with different versions. Manufacturers cannot test all the combinations especially when the Powerwall seems to get a new update every 6 weeks.

I would reset the car. Charge at another source and site and then talk to the dealer.
 
If it any consolation - and I know it is not really - even the cars from yesteryear had software issues:

the Vauxhall Cavalier SRi had a feature in its ECU that said if the fuel pressure was dropping, make the pump work harder/longer. It didn't know that the driver (me) had run out of fuel and that the fuel pump was now sucking the dregs from the bottom of the tank. This did two things: it bored out the injectors so that they flooded the engine and then created an air bubble that prevented new fuel to get through. End result was a recovery , 4 new injectors and a complete flush/renewal of the fuel system. My boss at the time was not happy with that bill.....
 
It is a nightmare for you but as someone who has been on the other side of the fence, i.e. having to write the software and then test it , it is a nightmare for the manufacturer. These systems only work because of the standards that define how they should interoperate but that does not stop tweaks and changes which can make or break a system especially when the system then relies on a slight deviation that gets tidied up without telling anyone else.

When I was with Motorola, we froze all the software that was running on the computers that were used to generate software because just little tweaks from the compiler supplier, Microsoft at al. These changes could mean the difference between something working and not working later. The issue of then having to track this down and fix it was horrendous so we did not allow any updates.

OTA is seen as an advantage but there is an argument of "if it ain't broke don't fix it". The Tesla MG5 charging program is an example of this in that the MG5s used to work but now with a couple of software revisions from TESL, the same cars no longer work. Tesla blame MG... Customers blame MG for not meeting the standards yet the reality is that it is more likely that Tesla changed something in the behaviour which MG did not know how to cope with. If Tesla had not made the changes, there would not be a problem. If MG had a better understanding of what chargers might do outside of the standard, the problem would be solved. Who is to blame?

As for overriding user settings... that will depend on the recovery strategy that is used. I used to reset the user settings if an unexpected error occurred because I did not know if the user setting combination was part of the problem! They might be valid settings but did they cause a chain of events that led to the problem. I could save them but then it would create a loop where the system would not not allow a recovery or opportunity to overwrite the "wrong" settings. When stuff bricks it is often because it is trying to do something in a loop with no escape opportunity.

Its like the display option on a PC - put in the wrong option and the display screws up. If the PC did not reset those display settings using a timeout, they could not be changed back.

As for combinations: Owners have Powerwalls with umpteen software versions, PV controllers from many suppliers with a charging unit from someone else all with different versions. Manufacturers cannot test all the combinations especially when the Powerwall seems to get a new update every 6 weeks.

I would reset the car. Charge at another source and site and then talk to the dealer.
Many thanks for your clear and thoughtful reply.

I hadn't appreciated the fact that overwriting user settings might be a necessary programming strategy to avoid loops, but from that perspective it certainly makes sense - even if it makes for a frustrating end-user experience ;-)

I've been reluctant to try workarounds in case I could be accused by the dealership of causing faults or invalidating my warranty; but the good people on this forum seem to have a much better understanding of the problems associated with this car and how to fix them than my local dealership do.

Unfortunately I don't have much faith in the latter: when the car threw itself into Reverse last month and nearly hit the car behind me, they initially didn't want to look at it at all ("Don't worry: it's just a glitch..."); and when they did finally agree to look at it, they told me "It's just like a home computer: sometimes you have to just switch it off and then switch it back on again".
Well, yes,I understand the analogy, but it's missing the all important safety-critical aspect:
Home computer crashes don't kill people: car crashes do...

So I agree with you and with the other contributors on this thread: whilst it is a problem that MG should be taking responsibility for, it's probably not worth the time and stress of taking it back to the dealership if all they are going to do is disconnect and reconnect the battery.
I'll do that myself; then try charging from a non-PV source; and if still no joy, return to the dealer as a last resort - hopefully a new software fix will be available by then.

Thanks again to all contributors to this thread for taking the time to read my woes and grumbles; and for sharing your experiences and expertise.
 
I'm charging my car direct from solar at the moment (and it seems to be behaving) because my G99 hasn't come through yet, so any excess solar is being given away free. Booo. But when the G99 comes through and I get an export tariff, I'll be able to get 15p a unit for solar export, whereas it will cost only 7.5p a unit to charge the car overnight. My intention at that point is to switch to charging overnight at the cheap rate and export the excess solar. It seems sensible.

Is there some reason why you're wanting to charge direct from solar long term?
 
I'm charging my car direct from solar at the moment (and it seems to be behaving) because my G99 hasn't come through yet, so any excess solar is being given away free. Booo. But when the G99 comes through and I get an export tariff, I'll be able to get 15p a unit for solar export, whereas it will cost only 7.5p a unit to charge the car overnight. My intention at that point is to switch to charging overnight at the cheap rate and export the excess solar. It seems sensible.

Is there some reason why you're wanting to charge direct from solar long term?
Hi - glad your system is behaving well at present!

I'm on Intelligent Octopus tariff, so it costs 7.5p/unit to charge my EV and/or Powerwall overnight, which is great; but when my system was working before these problems I could charge my car for free on sunny days from PV, and only use the overnight tariff to charge from the grid on days when there's insufficient sunshine for PV generation...

Yes, as an early adopter of PV, I also get a Feed In Tariff for generation, whether I use it myself or export to the grid; but it makes sense to prioritise use of the generated PV myself to charge the car or Powerwall, and then export any excess to the grid rather than vice-versa...
 
So... I've just powered down my MG4 using the Safety>Power Off setting.

Removed the Negative Terminal from the 12V battery.
Waited a minute.
Reconnected the 12V battery and powered up.

When the system powered up, it only asked me to calibrate the 4 electric windows in turn.
Not sure how to do this, so I just opened and closed them.
It didn't ask me to calibrate steering.

Good news is that the charging port LEDs are now working and the car is currently accepting a test boost charge from the grid via my Zappi.

Bad news is that it seems every single alarm in the book now seems to trigger during the boot up sequence (I've taken a video clip, but the forum doesn't seem to allow me to upload it).

Forward Collision System currently unavailable
Lane Assist System currently unavailable
Auto Emergency Braking currently unavailable
Speed Limit Recognition System Failure
Rear Drive Assist currently unavailable
EPS Performance Reduced
Stability Control Fault: Consult Handbook
Traction Control Fault: Consult Handbook
Autohold Fault: Consult Handbook
Hill Hold currently unavailable
Driver Drowsiness Detection System Unavailable

Also I'm getting a text alert from the MGiSmart app informing me that the steering calibration is faulty.

I've tried powering down the car and restarting it; but I get all of the same alarms each time.

I'm worried I might have rendered it unsafe to drive, and not sure what to do next.
I'd be very grateful for your advice...
 
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DRive your car for a bit and they will vanish as the car sorts itself out.
Thanks! Worrying moment there: I thought I'd managed to brick the car!
What about the power steering? It's sending me alerts about this but hasn't asked me to perform a calibration, so how will it know that the steering is properly calibrated and safe to use?
 
Thanks! Worrying moment there: I thought I'd managed to brick the car!
What about the power steering? It's sending me alerts about this but hasn't asked me to perform a calibration, so how will it know that the steering is properly calibrated and safe to use?
… see post #35
 
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… see post #35…

I thought it was going to prompt me to turn the steering wheel to both extremes at the appropriate moment during the re-boot sequence; but it didn't.

Does this mean I've missed the opportunity to calibrate the steering and need to repeat the process of disconnecting and reconnecting the 12V battery?
If so, at what point in the re-boot cycle do I have to turn the steering wheel to extremes in order to be sure it is correctly calibrated?

Many thanks
 
.. don’t think the order matters as long as you do it, try it now..
Thanks.

This time I didn't repeat disconnection and reconnection of the 12V battery: I just sat in the car and started it up.
Not so many warning messages as last time.
Whilst it was booting up and sending warning messages, I turned the steering wheel fully left then fully right, and the steering calibration warning icon extinguished itself, so all good there. ;-)

Despite Target Battery Level on the MGiSmart app and on the infotainment screen both being set to 100% (and not having reset themselves to 80% this time); the car only charged to 95% from the grid (I used the grid this time instead of PV) via the Zappi this time before the Zappi reported "Charge Complete" and stopped charging.

Maybe this is a software problem with the MG; maybe it is a calibration issue with the MG's charge management system following my hard reset; or maybe it is a problem with the Zappi...

I'll try to do a trickle charge to 100% via a domestic 13A socket and granny charger tonight in the hope that it will sort out any calibration problems and help condition the battery...
 
Thanks.

This time I didn't repeat disconnection and reconnection of the 12V battery: I just sat in the car and started it up.
Not so many warning messages as last time.
Whilst it was booting up and sending warning messages, I turned the steering wheel fully left then fully right, and the steering calibration warning icon extinguished itself, so all good there. ;-)

Despite Target Battery Level on the MGiSmart app and on the infotainment screen both being set to 100% (and not having reset themselves to 80% this time); the car only charged to 95% from the grid (I used the grid this time instead of PV) via the Zappi this time before the Zappi reported "Charge Complete" and stopped charging.

Maybe this is a software problem with the MG; maybe it is a calibration issue with the MG's charge management system following my hard reset; or maybe it is a problem with the Zappi...

I'll try to do a trickle charge to 100% via a domestic 13A socket and granny charger tonight in the hope that it will sort out any calibration problems and help condition the battery...
Not re-setting to default looks like progress, stopping to charge before 100% could indicate bad cell balancing or corrupt battery capacity data if this is indeed caused by the car. I take it boost mode is not activated on the Zappi or any other limit.

BMS information doesn’t get lost by a battery disconnect in my experience.

Cell balancing will be completed after the car is charged to 100% (or whatever limit you set your SoC), so leave it plugged in on the granny overnight.

However to do a calibration charge, you need to let the car run down below 10% leave it off for a period (30min? or longer) and then AC charge without interruption to 100%.

You’re meant to do this twice a year anyway so might be no harm to let the car recalculate the battery capacity.
 
Not re-setting to default looks like progress, stopping to charge before 100% could indicate bad cell balancing or corrupt battery capacity data if this is indeed caused by the car. I take it boost mode is not activated on the Zappi or any other limit.

BMS information doesn’t get lost by a battery disconnect in my experience.

Cell balancing will be completed after the car is charged to 100% (or whatever limit you set your SoC), so leave it plugged in on the granny overnight.

However to do a calibration charge, you need to let the car run down below 10% leave it off for a period (30min? or longer) and then AC charge without interruption to 100%.

You’re meant to do this twice a year anyway so might be no harm to let the car recalculate the battery capacity.
Thanks for the advice and explanation on cell balancing - very helpful.

Boost mode isn't activated and there are no other limits.

I did a granny charge overnight, and I'm pleased to report the MGiSmart app is reporting that the battery has now charged to 100%.
I'm planning to drive to London in the next few days which will discharge the battery from 100% <10%, so if I follow this with a Granny charge to 100% this should satisfy the requirements for the calibration charge; and I can do a similar thing on the return journey.

I was talking with a friend last night. He drives a Tesla 3 EV, but uses the same combination of PV panels, Powerwall and Zappi as me.

He uses a different approach to PV charging which uses the Zappi as a "dumb" charger, and the Powerwall as a buffer to smooth out fluctuations between PV generation and demand (from memory, the capacity of the Powerwall when fully charged is around 1/6 of that of the EV; so the Powerwall is fine to use to make up any small deficit in PV generation, but has insufficient capacity to fully charge the EV's battery on its own).
This avoids the need for the Zappi to start and stop charging when there are fluctuations in PV surplus, which might cause conflict with the software in the EV and cause the charging process to end prematurely.

When charging from PV surplus, he doesn't use the Zappi's "Eco+" mode. Instead, he makes sure that the Powerwall is fully charged, sets the Zappi to "Fast" charge mode, and manually sets the charging power on the Tesla EV to be a little bit (100-200 W) above the average PV generation level on that day. If the sun goes behind a cloud and PV output falls below the set charging current, the Tesla EV will draw any current needed to make up the deficit from the Powerwall. Similarly, if domestic appliances are turned on and temporarily divert PV generation from the EV, the reserves in the Powerwall acts as a buffer and make up the shortfall, and charging of the EV is not interrupted.

It requires a bit more user intervention than putting the Zappi into "Eco+" mode and leaving it do its stuff; but seems to avoid any interruption of charge to the EV which could cause the charging cycle to terminate prematurely. I need to experiment with this myself to see if it is applicable to the MG4, but I'm posting it here as a potential workaround in case anyone else finds it useful.

Thanks again to the community for your support and help over the last few days - greatly appreciated!

Update: The present firmware on my MG4 seems to only allow the AC current limit to be set at 6, 8 or 18 A : not sure whether there is another control somewhere that allows charging power to be fine tuned to match PV generation more closely, or whether this is planned for future software upgrades?
 
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Update: The present firmware on my MG4 seems to only allow the AC current limit to be set at 6, 8 or 18 A : not sure whether there is another control somewhere that allows charging power to be fine tuned to match PV generation more closely, or whether this is planned for future software upgrades?
This is one of the compatibility standard "holes". There are two operational factors that determine the charging current: the cable which is identified by a resistance that states the maximum current the cable can support and signals from the "charger" that indicates the maximum current it can supply. As long as the current taken is below both these limits - life is good. Go above and the charging process should stop to prevent bits overheating and melting.


Some interpreted this as being fixed limits as per the standard (including me) but others didn't and made the charger current limit flexible causing a "failure". Cue much gnashing of teeth because "your car" does not support the Type 2 standard when in fact it is the charger that doesn't. Easy software fix in my case.

This is where the limits come from. It may be that the MG4 charger can cope with intermediate values - I suspect it does - but that is why the main limits are there.
 
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It may be that the MG4 charger can cope with intermediate values - I suspect it does -
My MG ZS EV can heed control pilot duty cycles indicating current limits to at least 1 A resolution, so I'm sure that the MG4 can as well. Very likely, they could handle higher resolution than that (perhaps 0.1 A), it all depends on the on-board charger's hardware and firmware.

But there is another hard limit; there is no way to specify a current less than 6 A. It's just the way that the standard was written. That means when you have weak solar that can only provide say 4 A, you have to either pause the charging altogether (another area where the standard isn't crystal clear), or suffer 2 A of grid import or run the house battery down (if present).

Life is harsh sometimes for we poor first world citizens ?
 
My MG ZS EV can heed control pilot duty cycles indicating current limits to at least 1 A resolution, so I'm sure that the MG4 can as well. Very likely, they could handle higher resolution than that (perhaps 0.1 A), it all depends on the on-board charger's hardware and firmware.

But there is another hard limit; there is no way to specify a current less than 6 A. It's just the way that the standard was written. That means when you have weak solar that can only provide say 4 A, you have to either pause the charging altogether (another area where the standard isn't crystal clear), or suffer 2 A of grid import or run the house battery down (if present).

Life is harsh sometimes for we poor first world citizens ?
You can "interpret" the standard and actually signal below 6 A but it then depends on how the onboard charger unit is set up to respond. A further complication is how accurate does the waveform and the measurement have to be and what happens if it is on the border? Is it 5 or 6? The implementation issues are interesting to say the least.
 
This is one of the compatibility standard "holes". There are two operational factors that determine the charging current: the cable which is identified by a resistance that states the maximum current the cable can support and signals from the "charger" that indicates the maximum current it can supply. As long as the current taken is below both these limits - life is good. Go above and the charging process should stop to prevent bits overheating and melting.


Some interpreted this as being fixed limits as per the standard (including me) but others didn't and made the charger current limit flexible causing a "failure". Cue much gnashing of teeth because "your car" does not support the Type 2 standard when in fact it is the charger that doesn't. Easy software fix in my case.

This is where the limits come from. It may be that the MG4 charger can cope with intermediate values - I suspect it does - but that is why the main limits are there.
Agghh! That's a real pity, as my friend's workaround sounded like it might do the trick.
Maybe a future MG firmware upgrade might offer the option of setting charging current (or power) in smaller user-selected increments?

I guess another workaround is to cut out the Zappi altogether when I want to charge from PV surplus, and use the granny charger from the domestic 13A socket (which I think works out at around 2.3 kW). My Powerwall should make up any shortfall if the sun goes behind a cloud or the kettle boils...The charging speed will be slower compared than if I was using the Zappi (up to 5 kW); but at least it shouldn't quit prematurely.

I appreciate that EV technology is still in its infancy in this country. Whether it takes 10 h or 20 h to charge my car from PV panels is very much a first world problem, and I shouldn't get too hung up on it; but it seems that with just a bit more development and agreement of standards, a system that is periodically unreliable and currently relies on workarounds could work more efficiently and seamlessly...
 
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