PLC5 Ethernet Going to Sleep


Thread Starter

Jeremy Pollard

Customer has legacy PLC5/40E's. intermittent issues with communications where applications which would normally have <1second response time go into shadow mode and can't communicate. RSLinx has the dreaded 'X' thru the node on RSWho..

Sometime it comes back, sometimes not. A hard reboot of the PLC is

We have taken the network hardware, scan times, and bandwidth out of the equation, and for some reason there is always 'ONE' computer running the application (s) that will always communicate with the PLC.

Lots doesn't make sense.... just wondering if anyone has had similar issues and possibly any solutions.

BTW I hooked up a second PLC to the same network infrastructure thinking that if it was a broadcast storm that took the port away that the secondary PLC would go offline as such as well .... it didn't...

Any guidance/experiences appreciated.

Cheers from: Jeremy Pollard, CET The Caring Canuckian!
Crisis, necessity, change


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