Hi all…I have an EVCS, SmartShunt and Cerbo GX all connected and talking to each other in an OffGrid 3 phase system. I have the EVCS set to start charging at backup battery SOC of 100%, and stop charging at backup battery SOC of 95%.
The stop at 95% function works perfectly, but the start at 100% does not. SOC gets to 100%, and the EVCS will not start by itself. I have to switch it to Manual, wait for it to start, which it always does after a few seconds, then I can switch it back to Auto, and it will do a great job of regulating its charge rate to only use surplus solar, then winds itself back to minimum (6a) as the sun goes down until SOC hits 95%, and then turns off - perfect…HOWEVER, next day, after SOC hits 100% the EVCS just sits there doing nothing until I once again give it a kick by switching to manual, and back to auto again…
I set it to 98%, and it started about 30 seconds after it hit 99%.
I’ve just set it to 99% to see if that still works as well - I expect it will - but I probably won’t know for sure till tomorrow as it’s overcast and late in the afternoon now, so it probably won’t make 100% again today. I’ll update tomorrow.
Hi again Dean. Had a few heavy overcast days so today was the first time we got to 100% again - I can confirm with the EVCS “Start charging at backup battery SOC” set to 99%, it went to AUTO start shortly after the SmartShunt went to 100% SOC.
Well, that seems like a win. My thought was even if it was (“greater than or equal”) the slow charging curve at that point or rounding might explain that - but the xplanation from @M_Lange makes more sense and works for me.
I suspect, technically, that this is a bug in the EVCS settings interface.
Yes, you would think “Start charging at backup battery SOC” means exactly that, but it in fact is “Start charging OVER backup battery SOC”. IE, the programmed function is in fact “greater than”, not “greater than or equal”. Oh well - if that’s the worst “bug” it has then Victron have done quite well. I’m very impressed with how the Victron EVCS/SmartShunt/CerboGX combination manages energy flows in my off grid system. Better than anything else I’ve experimented with or seen on the market. to their design engineers.
soo simple…FIXED! Thanks Matthias!
to their design engineers.