F0091 fault in WEG CFW701 Drive indicates an External Fault. This means a peripheral safety device connected to the digital inputs has opened, forcing the drive to shut down safely.
Cause:
- A digital input (DI1 to DI8) programmed for “No external fault” is open.
Note: It is necessary to program a digital input for “No external fault”.
Remedy:
Check digital input terminal loops and ensure external switches are not triggering open circuits.
