Victron BMV712 and Strange operation

[johannvs (Johann)]

I’m looking for some help troubleshooting our Victron setup.

System:

• Cerbo GX
• Victron MPPTs
• Victron BMV-712 Smart Shunt/Battery Monitor
• 216Ah LiFePO4 lithium batteries

Issue:
The system will show 100% charged for a few days, operating normally. Then suddenly the shunt/system shuts everything down.

Once solar starts charging again and the system comes back online:

• Battery SOC shows around 99%
• But battery voltage is only around 11.5V

This obviously doesn’t make sense for LiFePO4 at 99% SOC.

Has anyone seen this before?
Could the BMV/shunt be losing synchronization or incorrect battery settings causing this?

Any advice on where to start fault-finding would be appreciated.

[Justin]

See the FAQs here:

Battery monitor jumping to 100% or reporting a high SOC with low Volts / the BMS shuts down

This topic covers the reported SOC being out of sync with the actual battery voltage or state. It covers BMV battery monitors, SmartShunts, Lynx BMSs and Lynx Shunts and will just be called shunt below. It is also assumed that the shunt is monitoring the domestic / house / cabin battery bank and not engine start / bow thruster / winch / caravan mover battery banks. The problems may be one or more of the following and is often linked to mobile applications with small solar systems. The SOC jum…