F554 tacho range fault in ABB DCS800 drive indicates that the tachometer signal received by the drive is outside the expected range.

1. Use a multimeter to measure the voltage or frequency of the tachometer signal.
2. Check the tachometer parameter settings, including the input type, range, and scaling.
3. Visually inspect the tachometer sensor for any signs of damage or loose connections.
4. Ensure that these settings are correct and compatible with the connected tachometer.