I'm currently encounter this error for the first time, my system using S7-1500H 1517-3 to communicate with 12 VFDs using FPNO-21 ABB, the problem is when not running the drive using PLC, everything normal, all connected and green. But when i start to control some drive at the same time, the communication is lost, for all drive, it's not completely lost but it connected and disconnected and go on forever. Did anyone know what could be the problems.

I've done something before asking on here:

Factory reset those FPNO-21

Change cycle time / watchdog time

Disable "Permit overwriting of PROFINET device names of all assigned IO devices" - It was enable the first time commissioning

Topic closed because the question has been posted twice. The active topic can be found here:

Communication Interrupt FPNO-21 PROFINET IO

Kind regards, Moderator_Lan