F1201 fault in WEG CFW900 Drive indicates a Slot B Initialization Error. This means the module in Slot B failed to initialize due to a resource conflict with another installed accessory.
Cause:
- The required operational resource is already occupied/allocated by another accessory.
- For communication accessories, only one node/accessory of each network type can be active on the inverter at a time.
Remedy:
Review Slot B accessory layouts. Ensure only one module is configured for each type of network protocol on the inverter at any time.
