Multiplus starts charging Battery when reducing minimum SoC

Hello,

I recently installed a Multiplus II 5000 with two Pytes 48100R batteries and configured it as specified in Victron & Pytes [Victron Energy].
Everything is running fine so far, but when I reduce the minimum SoC to 5% or 0% (from the default 10%) the Multiplus starts charging the batteries from the grid with full power as soon as the SoC drops below ~10%.

I’m unsure what is causing this and how can I disabled it? All the voltages are still above the voltages suggest (and configured) in https://www.victronenergy.com/live/_media/battery_compatibility:victron-configure3-setting-with-pytes.pdf. Any hints where I could look?

It has to do with the BatteryLife algorithm, if you are using it.
Try Optimized without BatteryLife.

I’m using Optimized without Battery Life:


Then for sure the developers though that less than 10% is not recommended at all and for sure is not good for any battery, regardless of chemistry.
I, for one, never went so low and didn’t know that also the “without” is behaving the same way.

It’s not recommended to go below 10% regularly.
The voltage of a LiFePO4 battery starts to drop faster below 15-10%.
Maybe the low voltage triggers the charging?
What battery do you have? What are the VE.config settings?

It’s not recommended to go below 10% regularly.

I know, but I want to do from time to time give the system/BMS a chance to calculate its SoC using the column counters correctly.

I have two Pytes E-BOX 48100R . VE.config is as specified in https://www.victronenergy.com/live/_media/battery_compatibility:victron-configure3-setting-with-pytes.pdf:

Setting Value
Sustain Voltage 49 V
DC input low shut-down 44 V
DC input low restart 48 V
DC input low pre-alarm 48 V
Absorption voltage 56 V
Float voltage 54 V
Cut off voltages 42 V

This graphs show one example of the recharge happening:

I decreased the minimum SoC below 10% at 20:30 and it immediately starts discharging the battery for ~15 minutes. Then re-charge at full-current kicks in. The voltage at that point is 49.9 V which is above all thresholds.