One or more cells approaching over-voltage protection threshold. Charging will derate. BMS ALM LED flashes green.
Common causes
Cell imbalance after many charge cyclesInverter charge voltage set too highBattery not reaching full SOC regularly preventing balancing
What to check
STEP 1
Allow a full charge cycle to maximum SOC — passive cell balancing only operates at high SOC (above ~95%). Check charge voltage setpoint in ShinePhone matches ARK spec
STEP 2
Monitor individual cell voltages in ShinePhone advanced view. If cell spread >200mV, allow several full cycles for balancing to act
Escalate if
Alarm persists across multiple full charge cycles with spread still >500mV — cell failure, escalate
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