Hello,

I am running OPC server for Allen Bradley which is connected to two PLCs. I am also running OPC server for GDA which is connected to a database. I am using the OPC Datamanager to connect all of these together and to log certain information to the database.

All of these components usually work but after about 3 hours of working properly, the items stop working in the Datamanager config program. I get errors of 'This item ID is invalid' and of 'RPC server is unavailable'. When this happens, I am then unable to see/access any tags in the PLC (which I previously had access to) or see any tables in the GDA/database.

Firewall has been turned off and as far as I can see all the RPC services are running. I would suspect RPC but I'm not sure if that is the case since everything runs smoothly for the first few hours. In some cases, after system reboot, I get the same error of invalid item right away.

I am running all of this on a standard windows 10 computer connected locally to the PLCs.

Any thoughts?