L32E Communication Fail

Hello all,

I'm experiencing communication problems with an AB L32E plc.

Seems for no reason the communication between the ethernet port of the PLC and PC fails.
So the process is running, parameters are being logged via OPC communication, all runs well and suddenly communication is gone.
Rslinx crosses my connection to the plc
Pinging the IP adress fails.

The only thing that seems to help is switching the PLC off and on again.

HW info:
L32E PLC rev 13.034
Ethernet port rev 1.3

Already searched through several posts, but nothing seems to solve this problem.

Any advise strongly appreciated.

BR

Can you check if you have alignment and FCS errors?
A similar situation happened to me once, and the solution was to set Auto_Negotiate port Speed and Duplex.

I hope it helps!

Is that PLC as well as all others in your facility on their own physical network? Is it on a managed switch? I ask because I had that exact same issue and when we moved all of our PLCs to their own network on managed switches, the problem went away.

People tend to overlook infrastructure and think as long as they hook up cables to both ends it will work. Nothing could be further from the truth. TCP/IP is NOT Ethernet/IP. The "IP" part doesn't stand for the same thing. Ethernet/IP is a shortened form of Ethernet Industrial Protocol. It does not play well with TCP/IP.

The "problem" is if you hook up a PLC to an Ethernet Network that is primarily TCP/IP, it will actually work...for a while. If there's only a few PLCs, it will probably be okay. But once you start adding things like touch screens and remote IO blocks to a network, bad things start to happen. And they'll happen randomly. And you'll fix it and it won't happen again for months. And then it will happen again.

An industrial Ethernet/IP network will ideally be physically isolated from any other ethernet network and be primarily on managed switches. If you have any other setup than this, trouble is an inevitability.