CompactLogix L35e - Lost Communication.

Hi everybody.
Does anybody know what is the problem, when CLX has lose communication via ethernet every 5-6 months?
CompactLogix have comm between others Compactlogix CPUs and HMIs..

This problem we have on a other PLCs ( Only L35e )

That's kinda like asking "why is my car not running well". It could be many different things including network issues not related to the PLC's. A lot more detail would be needed.

When you say 'losing communications' .. is that between PLCs, between HMI's and PLCs?

A problem that happens every 5 or 6 months sounds an awefull lot like a windows memory leak. There was really no fix, besides figuring out which HMI system needed patching.

The work-around (we use a lot of work-around to keep OPC working) is to reboot the PCs on the network more often. We reboot our OPC server every 2 weeks to sort-of keep it working.

When you lose communications, does it come back on it's own or do you need to do something to make the communications start up again, and if you do something, what is it?

Well, I do recall this seems to be a common problem with some Compactlogics. We have a system that's about 7 years old that had similar issues until I updated the firmware to version 20. So, update the firmware and see if that helps.