As I expected, the shunt has no effect on the SOC or behavior of the DESS. As can be seen on the screens, the DESS tries to bring the SOC to the predicted SOC at 10 a.m. by charging the battery from the grid at full power.
I have DESS disabled.
Hello Dirk-Jan,
Unfortunately, I have had the same problem for 2 days, DESS just doesnât work as it should, either the solar forecast is too high or the consumption is too high, in any case the system does not manage to synchronize it. The target SOC moves further and further away from the battery SOC and at some point the battery is charged from the mains, while I am in green mode. I took a screenshot every hour, here is the data:
07:45 BatterySOC: 42% Target SOC 50%
08:15 BatterySOC 44% Target SOC 35%
09:15 BatterySOC 42% Target SOC 50%
10:15 Battery SOC 49% Target SOC 77%
From 10:00 a.m. the battery was then charged from the grid and I switched off DESS again.
The forecast for the day clearly shows that the battery reaches 100% SOC, so why is it charging from the grid? Something seems to be wrong with my system in particular, as I am obviously the only one with this problem, I hereby ask for help!
07:45
08:15
09:15
10:15
The whole game is now repeated every day, so itâs pointless and only costs me money. Please undo the changes to my system!
You need to re-enable remote support first, so I can do that.
The system is open. Can I leave this open or can anyone with my ID access it?
There is also an error in the interpretation of the current flows. Between 9:00 a.m. and 10:00 a.m. today definitely 0.3 kW went from the mains into the battery, the screenshot from Victron says otherwiseâŚ
First of all, that change had already been undone by updating your system to 3.42. So instead of reverting it, I have re-activated it now. FYI it is changing the value of 0.9 to 0.85 on line 148 of this file and restarting the dbus-systemcalc service.
It is always safer to close the remote support if it is not needed (so you can now close it again). But even if it is open, people with only your ID would not be able to access it without credentials.
Iâll look further into your system on Monday; didnât get to it last few days because of other priorities.
Thank you and have a nice weekend 
Something may be wrong in your numbers and evaluations. Today between 10:00 a.m. and 11:00 a.m., 0.52 kWh was charged from the grid into the battery. In my opinion that makes no sense, but the number is correct. From 11:00 a.m. to 12:00 p.m., according to your figures, 0 kWh was charged from the grid into the battery, that canât be true, my own control shows me almost 0.76 kWh that was charged from the grid into the battery.
10:00 a.m. to 11:00 a.m.:
Where does the 0.3 kWh grid to consumption come from? The battery was at 50% and everything from the grid was charging into the battery!
How do you calculate that or how can you differentiate?
As mentioned before, the numbers are based on a best effort estimate of how the energy flows in the system. Your system doesnât have a smartshunt or battery monitor yet, so we need to make due with the information that is available.
Btw weâve just put that new graph on beta VRM.
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The smartshunt has been running for 5 days, the difference to the battery monitor offered by Victron in the ve.configure is almost undetectable, i.e. marginal.
The problem can be reproduced and occurs for me almost every day between 9:00 a.m. and 12:00 p.m. The battery is charged from the mains because the charging power of the charger is not reduced. And so the electricity comes from the grid.
Just like a new problem that has been occurring since yesterday, when the battery is 100% charged and the forecast says 100% at the end of the hour, the battery is not discharged, but the power also comes from the grid. This happened to me yesterday between 4:00 p.m. and 5:00 p.m. and today between 15:00 p.m. and 16:00 p.m. Based on my data you should be able to understand that.
You know, I have now invested around 400 euros to use the DESS because I am convinced of the principle. Iâve been trying around with it for weeks now, writing posts to help you further develop the system and remove the bugs, but I have the feeling that nothing changes on my system. On the contrary, in my opinion there are always other things that donât work as they should. This is frustrating.
Same, I disabled DESS 2 months ago for exact this reason (âCharging in the morning, even with enough solar predictedâ).
Now I enabled it again since winter is comming and couldnât see this happening again in the past 14 days.