Low battery warning after MultiPlus firmware upgrade to ver. 552

After upgrading MultiPlus from ver 1xx to 552, the blinking red light on its MultiControl comes on (low battery warning). SOC of my two battery banks is better than before the upgrade. Indicated voltage on the BMV712 is 13.1, and the Multi sees it as the same (when I check through the CerboGX interface). The battery level is 34% - this was sufficient to operate the inverter function before the firmware upgrade. However, now the Multi refuses to turn the inverter function ON. So we suspect that there is some parameter in the new Multi firmware that controls this “low battery” warning Any ideas as to which one it may be? TIA

Did you check all settings of the MultiPlus with VE.config?

yes, we did. They were: DC input low shut-down 11.6V, DC input low restart 13.2V, DC input low pre-alarm: 13.2V. Shut-down on SOC was checked and the SOC low shut-down was set at 10%. From these settings, the DC input low pre-alarm and DC input low restart (13.2V) were observed in practice, i.e. the low battery alarm came up when the voltage dropped to 13.2V, and the Inverter did restart once the sun was up, and the MPPTs charged the batteries a bit. But what was NOT expected is the inverter shutdown so quickly after the low batter alarm was raised. To fix it, for now at least, we have lowered both the low pre-alarm and low restart to 12.1V, while keeping the low shut-down at 11.6V. Any ideas for why the shutdown would happen near 13.2V as well?

The restart voltage is a bit high in my opinion, also the pre-alarm.

Your problem was the high restart voltage.
After a reset of the MultiPlus (switching off-on or a FW update) the battery voltage needs to be over the restart voltage.

I would set the pre-alarm 0.5V over the shut-down and the restart 1.0V over the shut-down

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