Once or twice a day our Allen Bradley PLCs stop communicating and show “Idle” status on our development servers and we’re not sure why. We’re using version 8.1.1 at the moment.
On this project we have two tag servers, and one client server to deal with our high tag count. Initially in the project we were using one server, and it was getting overloaded constantly as we were adding tags, and the PLCs would commonly go into Idle status. Once we split out our servers however, the memory and CPU on the servers never get too high, and communications seem to be working decently well, but we still see devices dropping into “Idle” state and not coming back until the connection is refreshed through the gateway.
I’ve tried increasing and decreasing the Max Concurrent Requests, as well as the timeout parameters to no avail.
We’re actively developing on these PLCs, and sometimes during tag imports some PLCs go Idle, then back to Connected within a second or two, but sometimes they just get stuck in Idle.
Has anyone else had this problem?