I have my Quattros and Cerbo set up in an ESS configuration. During the solar storms, I manually disconnected grid power. I set up the ESS "Minimum SOC (unless grid fails)" setting to 20%. I also set up the generator to automatically start if battery SOC reached 15% and for the generator to stop if battery SOC reaches 30%.
On one of the days, the battery SOC fell to under 20%. At that point, the essential loads were disconnected, i.e. the Quattros were not supplying any power. So the "Minimum SOC (unless grid fails)" setting behaved more like "Minimum SOC (even if grid fails)". The generator, however, did not start, because the SOC did not fall as low as 15%.
Thankfully, I have a UPS at the output stage and I noticed after about 1.5 hours that I was being supplied by the UPS. At that point, the battery SOC was 18.5% or so. I do not know why the batteries dropped to 18.5% during those 1.5 hours - maybe supplying my Victron equipment? I manually started the generator to recharge the batteries.
Why did this happen? Is there any other setting I should be looking out for?
My load was about 3kW at the time and I have two Quattros wired in parallel capable of supplying 30kW on the inverter output, so there was no possibility of an overload.
Thank you.