Fault Messages from Different Profibus Nodes

Hello,

I have profibus problem on my machine.  There are profibus faults from different profibus nodes.

You can find alarm list and hardware configuration on the attachments.

How can i solve the problem or find the reason?

Thank you.

Hello seko;

The best source of information on the cause of the faults in your system is to open the diagnostic buffer of the PLC (what you show from your alarm list is the presence of the fault, without explanation).

You can open the diagnostic buffer with CTRL+D, or with the menu PLC-->Module Information, Diagnostics tab, or by opening the Online view of the HWConfig editor (which you show in your screenshot), and double-clicking on any module (including the CPU) that shows a red slash icon, indicating a fault.

In the diagnostic buffer page, use the Save AS.. button to generate a text file containing all logged messages of the diagnostic buffer. Attach this file to this thread so we can have  a look at your buffer, and try to make sense of what could be causing the alarms.

Hope this helps,

Daniel Chartier

Hello,

Here is the diagnose file.

There is no change on the problem.

We take fault messages from different nodes almost 10 times a day.

Here is the short example from the file.

"I/O access error, reading" events related to "Distributed I/Os: station return" events.

Thank you for your help.

Hello seko;

If I had such a diagnostic buffer upload, I would be worried about my network installation. 

The OB122 calls refer to station addresses accessed in your CPU but not located through the network, so they coordinate with the OB86 calls (station failure).The number of failing stations would cause me to think that you have either a termination issue (losing power on one of the endstations, which causes reflections on the bus that can lead to station failures) or cabling issues (bad wiring, non-connected shield in the connectors...). Vibrations on the installed nodes can also cause intermittent loss of contact with the master.

Look at the following basic documents, they should provide suggestions on what to look for on your network hardware:

https://us.profinet.com/top-5-reasons-your-profibus-network-failed/

https://www.profibus.com/uploads/media/pxddamkey%5B9099%5D_PROFIBUS%20health%20checking-Andy%20Verwer.pdf

http://www.ad.siemens.com.cn/club/bbs/upload/2008/20080331/69691140TroubleshootingandMaintenance-DennisvanBooma.pdf

Then take a tean out and systematically examine every node on the bus for proper termination and adequate connections of the cable and connectors.

Hope this helps,

Daniel Chartier

Hi,

We solved the problem on the planned maintenance (that because of my late answer).

There was a unplugged profibus cable on an encoder's socket.

Thank you your help again.