Cause : External temperature 1 comes when measured temperature 1 has exceeded fault limit. This fault or warning indicates that the temperature measured by this sensor has reached a critical level or has exceeded the set limit.

The fault code 4981 in your ABB ACS560 drive indicates an external temperature 1 fault. This means the drive has detected an excessive temperature reading from an external temperature sensor connected to it.

1. Check the value of parameter 35.02 Measured temperature 1.
2. Check the cooling of the motor (or other equipment whose temperature is being measured).