I am still noticing odd behavior in terms of Tag read/writes and scan classes.
I have noticed that sometimes clicking a button to write to a tag instantly writes to the PLC, but sometimes there is a considerable delay (1-4s).
I have played around with different scan classes (direct and leased) and there doesn’t seem to be a true correlation yet, it seems pretty random.
My questions is:
Does Ignitions OPC Server ensure tag writes are sent to the PLC instantly, regardless of scan rate?
If so, what might be causing a delay between Ignition and the PLC?
I have looked at the System Console -> Execution and all of my scan classes seem to be executing with reasonable durations.
I am using Ignition 7.8.3 on a Debian server with ~ 18000 tags on the Omron driver (v1.8.3) connected to an Omron NJ501 PLC.