FoxESS
ECS: Relay Adhesion
Main Relay Stuck Closed (Welded)
Battery internal main contactor is stuck closed — cannot open when commanded. Safety hazard.
Common causes
Relay contacts welded from overcurrent eventControl circuit failure
What to check
STEP 1
Power off completely: DC switch off → hold POWER button for 5 seconds → wait 5 minutes. Power on and check if fault clears
STEP 2
If fault persists after power cycle — relay is physically welded. Do not continue to operate the battery
Escalate if
Always escalate relay adhesion — this is a safety-critical hardware fault requiring unit replacement
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