While updating various settings, I stumbled upon a potential safety issue in regards to battery charge behavior. I've seen this before, but was unsure of the trigger at the time.
Relevant inverter settings:
- Charge > Operating Mode > Use SoC %
- Charge > Charge first (PV) > checked
- Charge first power (kW) > 2.0
- Stop charge first SOC % > 95
- Stop charge first Volt (V) > 56.0
Testing conditions:
- Allow batteries to charge fully. In my case, charge stopped at 95% (expected)
- Restart inverter
Observed behavior:
Inverter resumed charging batteries from PV, beyond 95%. Allowed this to continue, maybe it would stop at set voltage? Observed it did not. I reset charge current down when voltage measured 56.1 to prevent BMS OVP from kicking in (this is what I saw in the past, but didn't think much of it at the time). Screenshot attached - note voltage, SoC, and charge current still at maximum power.
Edit: performed additional steps in an attempt to gather more data
- Changed battery charge current limit from 40 > 20A, for additional margin of safety
- Observed charge limit value takes effect immediately without reboot
- Changed stop charge first V to 54V (wanted to see if it would stop here, as SoC is being ignored)
- Did not stop. Currently at 56.3 and climbing. Note - I have not yet restarted the inverter after value has been updated.
I'm not completely sure if the primary trigger is changing these settings while within the specified active timeframe, or the reboot within the timeframe (could be both?). I won't be able to do any more testing until tomorrow. Anyway, this is what I have for now.