Evnex E2 EVSE overriding solar setting

Having been away last weekend we added an exception to our Solar Diversion for overnight charging prior to heading away. This exception has since been removed but it seems like the E2 is choosing to import from the grid for random periods when it shouldn’t be and is now giving a “Charging will resume once grid load is reduced…” message even though we have sufficient solar export occurring to supply the EVSE.

Any clues as to what is going on here?

ETA: Now the E2 is drawing ~6kW from the grid (according to our inverter’s data) despite being set for solar only. The Evnex system is quite ‘laggy’ but it seems to be well out of kilter today.

What I can see in the logs is that the charging profile was cleared at 10:14am on 9th July - I can’t see exactly how this was done but it looks like it was via the app? This meant that the charger reverted to just always charging at full speed.

What confuses me is that it appears there was a car plugged in at the time but it didn’t charge. Then another car (or perhaps the same one?) got plugged in nearer 12:20 and it immediately charged at full speed, as I would have expected.

Do you by any chance recall what you did in the app which would have led to the profile getting cleared? I have a suspicion that perhaps this was turning off the schedule, and a bug has crept in whereby instead of returning to “solar only” it instead returned to “full speed only”.

Tom

Hi Tom,

Isn’t the phone app the only access I have to changing charging profiles? I don’t remember using the phone to change settings yesterday morning but if so it would have been intending to revert back to solar diversion only from the override I had set for the previous night charging session from midnight Thursday night (4th-5th). The setting of charge now exclusions I find to be clunky with having to change both Solar Diversion and Scheduling pages.

Can you shed any light on why the charge event that started at around 5:20pm on 8th only went for about 2.5 hours? Also why did the charging event on 9th dropped off at around 2:00pm and then resumed again until I disconnected at 3:15? We also appear to have exported ~1kW around 3:15 according to our Fronius logging though this may just be due to monitoring lag of either the EVSE or inverter (more likely the EVSE). The discontinuation of the charge on 9th coincides with the “Charging will resume once grid load is reduced…” message even though we had sufficient solar export occurring to almost supply the EVSE exclusively.

I investigated the app settings completely yesterday evening and it now appears that the EVSE is performing correctly. Incidentally we only charge our Polestar using the Evnex as our Leaf has a type 1 socket which we connect via an older Juicepoint EVSE.

I wasn’t sure if you were part of any trials where profiles get controlled, or else you can also use the physical “Charge Now” button on the E2 which changes profile settings.

We’ve been doing some experiments and it looks like as I guessed this morning, there is a bug whereby turning off the schedule reverted to a “charge from the grid at any time” schedule (which is what you want if you don’t have solar) instead of a “charge only from solar” (which is what you want if you do).

Sorry about that, we’ll get a fix out hopefully this week or early next.

As for the shortened session on 8th, at 7:54pm the car stopped consuming energy from the charger. We can’t see why it chose not to, but I can see that we were still offering it to charge. It could be various factors - reaching a state of charge limit, perhaps an internal end timer in the car, even a temperature limit (some cars don’t like to charge when it’s very cold or hot - but I doubt you were at either extreme).

Something very similar happened on 9th, with the car slowing right down at 1:30pm and then stopping charging altogether at 1:45pm even though it was still being offered to charge. It then chose to start again at 2:11pm, despite no change at the charger end.

At 3:05pm it looks like the solar settings were restored, so after observing a minute of export it began charging at 3:06pm, and was subsequently stopped at 3:14pm.

Our logging indicates that between 3:10pm and 3:15pm about 0.03kWh in total were exported from the house. The charging session ended about 20s before the latter reading - we see cumulative import and export every 5 mins. The “grid load” message may have been due to the timing of when messages were sent leading the app to conclude that the car was plugged in when it wasn’t, and so it thought charging speed was lower than it should have been? I’m not sure - if you see it again and can let me know what was going on around that time I can have a more detailed look.

Tom

Thanks for the info Tom. Our trip away was in part to get the Polestar serviced which included a software update. The new software version includes the ability to set the car’s charge limit via the phone app which may explain the early session end on the 8th. In attempting to correct the unwanted charging scheduling I made some changes to the car’s settings on Monday night which possibly included raising the charge limit so on the 9th it resumed charging as a result of the bug you have identified. The break around 2:00 is a mystery to me especially in regard to the grid load message. From what you are saying it sounds like the concurrent charging and export stated by Fronius is likely to be a mismatch of data monitoring timing between Evnex and Fronius as I suspected.

I don’t usually observe the charging in real time, especially as 95%+ of our charging is by way of solar diversion, but will make a point of doing so next time we set a grid demand schedule and let you know if anything unusual occurs.

Cheers,
Tony