Cause : FPTC not found comes when a thermistor protection module has been activated by parameter 35.30 but cannot be detected.

The fault code 4990 in your ABB ACS880 drive indicates a general external sensor fault. This means the drive has detected an issue with an external sensor connected to it.

1. Power down the control unit and make sure that the module is properly inserted in the correct slot.
2. The last digit of the auxiliary code identifies the slot.