Hi,
is it possible to manually select the power source from which the EVCS should take the energy?
In winter my pv doesn't produce enough power in order to charge my car. I was told that is not good for the battery when it is discharged "very" fast and as the wallbox can charge with 22kwh it would be better to take the energy from the grid and not from the battery as sooner or later my battery will get empty.
Any ideas?
Hi @StefanWB, as far as I know, this is currently not possible. However, you can set the SoC of your ESS above the current battery level before charging and thus prevent using (any) energy from battery. Just don't forget to set it back afterwards.
But you could probably also automate this with NodeRED (using Venus OS Large).
I had a similar idea and my solution was a little Node Red Flow.
First I created an entry in the Scheduler Tab of the EVCS (eg. daily between 02:00 and 05:00) when the EV is allowed to charge.
In order to avoid using battery power the Cerbo will check the following 3 conditions via an AND gate:
If all 3 condtitions are TRUE the inverter power is reduced to 200W which is my average basic consumption during nighttime (could be set to 0 as well).
Once the EVCS reaches the preset charge limit the EVCS status will change from CONNECTED (1) to CHARGED (2) and the result of the AND gate becomes FALSE. Then the inverter power is reset to the previous setting.
In a future version I want to use one of the Cerbo's relays to automatically switch between 1P (for PV excess usage) and 3P (for nightly usage) charging. This is done manually at the moment with only reduced WAF ;-)
Feel free to ask if more info is required...
Best regards, Jochen
Hi,
thanks for your Flow. Would you mind sharing your xml-file?
I'm a total Node Red newbie but I'm fine with Java so I'm no programming newbie. However, I'm a bit afraid of destroying/damaging my wohle victron installation when trying something on my own in Node Red - is this fear real or is there some kind of "simuation mode"?
Best regards
Hi!
I understand your concerns about simulating first and can only suggest to troubleshoot and try best as u can before going life. The best thing you can do is to use debug nodes first wherever data would normally be fed into you system and not send anything initally. A bit tedious but workable IMO. And also remeber that the flows will continue running after closing your browser and shutting down you computer. Don't ask me how I know...
No problem to share the flow however PM seems not to be desired here in the community (unless I'm blind) and the flow exports as a JSON file which is not an accepted file format. Can I rename the flow.json as flow.txt without losing any content? I'g think so and give it a try.
It is worth mentioning that I'm working with dynamic inverter power settings, so you would have to replace the part where I switch back to flow.power_today with your fixed normal inverter setting.
Let me know if the file imports ok...
Best regards, Jochen
I had the same challenge. When using scheduled charging (e.g. because the price is low) I do not want to use the batteries as the source.
This is not possible with the standard Victron settings. So I wrote my first node red flow.
When the EV charger is using a schedule to charge the car, the grid setpoint is set to the used power (dynamically) of the charger. When finished it sets it back to 50w. It needs ESS to function.
Normal loads will still come from the battery. When the battery is charging from the grid, the grid setpoint is ignored by the Victron system.
It is easy to extend this also to manual charging.
See attached .json file. (rename .txt into .json after download)
