I have a Multiplus 2 with a smart shunt and five 100AH AGM batteries connected in parallel. I also have solar panels with two MPPTs that charge the batteries when not on shore power.
The problem - the batteries can be at a full state of charge with a voltage of 12.8V. If I run a heavy load like the microwave, the voltage will drop instantaneously to ~12.1 volts which will cause a low voltage alarm to trigger. When the heavy load is removed the voltage returns to 12.8 volts.
I measured the voltage at the batteries and confirmed that there is less than 0.1V drop between the batteries and Multiplus 2.
Is there some way to dynamically set the low voltage cut off based on the battery state of charge to prevent this from happening?
I don’t want to just lower the threshold since under a light load and low SOC the batteries would be over discharged.
I appreciate and help that you can provide.
Thank you,
Ralph