FoxESS
ECS: Under Voltage

Pack Under-Voltage Fault

Battery pack voltage has fallen below the minimum threshold. Charging halted, discharge stopped.

Battery deeply discharged (left off-charge >7 days)Single cell at 0V (dead cell or broken sense wire)DC cable resistance causing false voltage drop
STEP 1
Check SoC on Fox Cloud. If at 0% and battery has not charged for >7 days, deep discharge damage may have occurred — recovery charge needed via inverter force-charge mode
STEP 2
Inspect DC output cables close to battery terminals for damage, kinking, or high-resistance connections. Measure actual voltage at battery DC output terminals
Voltage is below minimum under no-load conditions — possible dead cell, escalate to service.uk@fox-ess.com
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