Hup loses slew function sporadically, will sometime cause other drives to shut down with Cof fault. This is often an error with the slew motor encoder failing or shorting out. The drive sends a stop command AFE1 or 5091 to power down the drive which then shuts down the other drives.
The drive will often fault and shut down before registering a fault in the CCS. Check the fault history of the ACS380. If an encoder fault is present like 7301 – Motor Speed not detected,
Replace the motor encoder
If an encoder isn’t available you can remove the encoder wiring from the drive and it will default to estimated speed.