In this system the MultiPlus is the battery monitor.
If we set min SOC 5% everything is fine. Multi stops discharging the battery at 5% SOC.
Question:
If we set the SOC 0% the Multi continues discharging the battery.
Is this a normal behaviour?
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In this system the MultiPlus is the battery monitor.
If we set min SOC 5% everything is fine. Multi stops discharging the battery at 5% SOC.
Question:
If we set the SOC 0% the Multi continues discharging the battery.
Is this a normal behaviour?
Maybe a dumb question, but why on earth one would want to discharge a battery to 0% SOC?
Now onto your question, the logic inside ESS is based on 5% increments and decrements.
No, it's not normal behavior and maybe somewhere, in programming, a check is missing for these (almost nonexistent) cases below 5% SOC.
Afaik, if you set SoC to 0%, the system will keep discharging until stopped by the BMS, or until the low voltage threshold is met. Which makes sense in a few situations.
I've set my systems' SoC to 0% a few times on purpose, to bring the batteries all the way down, in order for their BMSs to properly calibrate at the bottom. It turned out that they were hiding around 10% of capacity.
Thank you for all the comments.
Of course discharing (until it the cut off voltage of the battery is reached) to SOC 0% is risky. It was just a question to understand the system better.
I agree a BMV is a much better measurement than the internal Battery Monitor of the Multis.
So there is no ESS regulation at the SOC limits (0% and 100%).
ESS design and installation manual
Additional resources still need to be added for this topic
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