Beckhoff System stability

[AgentB]

Hi All



we have a machine with a Beckhoff PC Controlled plc system.
We are having endless problems with the stability of the system and cannot find out what is going on. Hopefully someone with more beckhoff knowledge will be able to assist.


Basically what happens is that the machine stops working. When we look at the system control we see errors of modules changing between int and op. ant the topology will show a red dot by the same module. Sometimes restarting the machine a few times and the problem goes away. Sometimes we end up replacing the modules and this corrects the problem. What is a concern is the rate at which we are changing the modules almost weekly.



We got called to the machine yesterday and the machine showed 11 faults. Please see attached picture. Can someone please give some insight into what is going on with this machine.

 

[JesperMP]

No experience with Beckhoff or Ethercat.

But EMC ?

 

[LadderLogic]

Hard to be specific with an unknown system. But the things like checking all the networking cables/components for proper shielding/noise suppression and verifying there is no excessive vibration that might disturb terminal-to-terminal connections are probably a good start.

Also I see the machine is pretty old (TwinCAT 2 and K-Bus EL terminals as seen on the screen). Maybe it would be prudent to carefully pull out each terminal and just wipe the communication contacts with alcohol? Especially if it has been or is working in some not particularly clean and dry environment.

 

[AlfredoQuintero]

Agree with LadderLogic. If the software has not changed then it has to be something physical and bad contact is one thing that can happen with time especially if the environment is not clean. Also, I recommend you check the LAN cables.

 

[busarider29]

The root cause of the problem does not appear to be the system. Replacing modules and that "fixes" the problem tells me that there's something with the power supply and/or main power infeed. If you want to replace anything, try replacing the EtherCAT bus module that feeds the I/O. If the problem still periodically persists on various I/O in the tree, then again, it's something else outside the system related to power. How old is the system?

 

[ndzied1]

What would really help is knowing if the system ever worked. Has this problem always been present on this system or has it worked for a time and then the problems started.

The answer to this will help you know if you have to question the design itself or if you are looking for product / cable failures or other things that have changed.

 

[LadderLogic]

K-Bus EL terminals

Sorry, that was me lost in the alphabet soup. The K-Bus terminals are KL, not EL. Disregard this observation.

 

[Mara]

Just make a phone call to Beckhoff. It's fully free of charge. They will take remote connection to your system and will check what's wrong

 

[LadderLogic]

That is what I wanted to add too: I can't speak for other countries but in the US Beckhoff's tech support is excellent and they will go out of their way to help, including a visit to you, free of charge.

They understand they make money selling their product, not charging their existing customers for support. Who, in turn, like their product even more.