F104 fault in WEG CFW900 Drive indicates an A/D Converter Error. This means the internal analog-to-digital converter has failed to read currents and voltages properly, indicating a hardware defect.
Cause:
Fault reading the A/D converter that measures the inverter currents and voltages.
- Defect on the inverter internal circuits.
- Electromagnetic interference above the level the inverter withstands.
Remedy:
Inspect control module circuits. Verify that general installation grounding, cable shielding, and panel layouts are properly set up to mitigate EMI.
