Breaking EG4 14.3kWh indoor wall mount battery BMS comms issues - resulting in blackouts, power blips, and charging restarts

@clarktheshark 

My system is set to charge batteries to full both from PV array during the day and from grid overnight  and batteries get charged to 100% regularly, yet looking at the inconsistent voltage/SoC data when run in lithium mode I suspect the BMS is getting "off" after few months and start throwing some momentary error inputs to inverter (like low voltage, no battery, etc.) which causes the subject issues. The data is logged only every 4 min. so it is very difficult to capture those very instances and in most cases we can only see the inverter recovery from BMS hiccups.

From my experience after running for months in Lithium type 1 mode the subject problems start occurring (after 4 months in 20056  and 6 months in 2026). In both cases I switched to Lead Acid mode for couple of days , updated the firmware and power cycled the system as remedy

This year when the issues reoccurred the deep power cycling of the system alone did not help. Only after switching to Lead Acid for couple days  the firmware update and system power cycle solved the issue.

I am guessing, but maybe the top balancing the cells (read: couple cycles of charging batteries to full using voltage setting) is the fix?

Have you tried to top balance the cells in your batteries (set up the system in Lead acid mode and set the charging voltage to 56.4-57.0v and charge the batteries to full - in some sunny day or from the grid)?

Again, It is only my guess, yet putting the dots together make me think that the firmware update is not the primary fix, as in both cases the system worked flawlessly for months in Lithium mode running previous versions of firmware.

Just my 5 cents to share.

Brgds

K

I have always charged using SOC. 

I have mine set to charge from 20-75% using grid power, regardless of the time of day.

I would say it's a weekly occurrence that the batteries reach 100%. 

From everything I can tell, the cell voltages are all very close together even when the batteries haven't reached 100% SOC in a week or two. 

I don't think it's a low voltage issue also because the problem usually occurs during peak PV charging. 

Based on the logs, I'm seeing the battery comms just stop and restart. 

- The inverter should not just freak out immediately in that scenario and cutover to grid. It should absolutely wait 10 seconds. During that 10 seconds l, it could fallback to Lead Acid mode maybe....