FoxESS Community - Owners & Installers Forum

[EDIT - Ok, after maybe 5 minutes the inverter DID do exactly what I wanted it to do! I was impatient I guess. Posting this anyway for posterity and comments -- see screenshot]


Hello!

It's pretty sunny, my battery stack is at 97%. I usually leave Max SOC at 95% in case my battery gets used a bit but then I have surplus and I want it to export instead of charge my battery back to 100% (this is in Self-Use mode).

Now I have enough sun that I should be producing about 2000 watts, but the inverter will not 'recover' from the reduction in soloar generation (reacting to the power cut and sudden need to stop export) and begin charging the battery (this is after I have changed back to Max SOC 100%).

It is still drawing power for the house load partly from battery and partly from solar. It should increase solar to cover house load and start charging the battery.

It seems this is a firmware issue. Thoughts?

Only thing that I might suspect is that at 97% the BMS usually cuts the charge power particularly if it had recently been at 100% SoC - I think it’s to avoid continuous charging of the battery when it hits 100% and it usually takes a while before it allows the charge again (a bit like a hysteresis profile). It’s certainly a regular observation that people see their battery not charging at 97% because of this.

If you have full history enabled on your modbus, see what the sensor BMS Charge Rate was showing for that time period - my guess is it will be 0A

Hi Dave .. thanks. I don't have that attribute enabled to check it.

It had been sitting at 98% starting about four hours prior, then 97% for about 50 minutes before the power cut when I asked it to start charging to 100. I'm not too fussed since it did eventually start to charge -- obviously I started writing the post before it did, and I had observed this behaviour on other occasions as well.

But for example when the grid is restored and there is power to export, the inverter ramps up the solar and export power much faster.