Battery DC cables are connected with reversed polarity. This is a critical safety fault -- do not energise.
Common causes
Incorrect wiring at initial installationCables swapped during battery replacement or maintenance
What to check
STEP 1
ISOLATE DC IMMEDIATELY. Do not attempt to restart. If the inverter was energised with reversed polarity, internal damage is likely. Reference the SPH Battery Terminal Connections wiring diagram for correct BAT+ BAT- positions
STEP 2
Identify which cables are reversed and correct polarity before reconnecting. Inspect terminals for signs of overheating
Escalate if
Any components show signs of damage (burning smell, discoloured terminals) after a polarity reversal -- escalate before reconnecting
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