Hi Drives experts,

we have 32 Siemens master drives running on profibus with S5 155U on Im308c. Now one drive 37Kw 6ES7027-2ED20 running with CU2 and CB1 card became faulty. we Have another Spare 45KW (6ES7031-2EE20) Drive. we installed 45KW drive in place of 37Kw drive, we installed CU2 and CB1 card. with drive monitor software we reset parameter, change MLFB no. and download old parameter file to drive, then change profibus address and then fix profibus. drive give OK status. Then we started with profibus it run ok. after some time two different dive on this profibus tripped with F082 (communication fault). we try it two time but same result while profibus address is same as before.

Please Help me why is it happen?
Regards,
__________________
Zahid Ali Khan.

Rox Tech Engineering.
Township Lahore,
Pakistan.

 

Look at the connectors first, then the cable, then the grounding and cable routing. It is pretty unlikely that two drives failed at the same time so I would assume a noisy bus until more clues occur. Make sure the terminator is on at the end and off everyplace else, etc. And of course, check everything you changed very carefully, or better, have someone else check it. It's easy to consistently overlook something you assume is OK,

Regards
cww who has spent plenty of time chasing Profitbu$ errors.

 

First things I always check for with Profibus network issues is that the termination resistors are active at both ends of the line.
As Curt said, you need to check the connectors have been made off correctly.

Another thing you could try is to temporarily reduce the speed of profibus network which is then more resilient to noise and bad terminations. However, once that is done you should always then check the terminations to prevent any further issues in the future.