I have a situation that I can't get my head around and was hoping someone could help me work out what is happening.
We have a number of PI Points coming through a legacy Yokogawa ACG Interface. On the 12th around 12.30pm the tag values changed as follows:
As can be seen it appears that the compression settings of the point have been changed. At approximately the time this change in sensitivity occurred there was a bulk update of pi points changing the security configuration. I have the extracted PI Point details before and after the security update and the compression and exception settings remain unchanged.
I have made a test version of this tag which is coming through an ExaOPC interface to determine if the interface is the cause of this issue; however both the ACG and ExaOPC Interfaces show data updating with the compression settings applied.
Looking closely at the data it appears that before the behaviour change the exception settings were being applied but the compression settings were not. After then pi point security update, the compression settings have started being applied.
I am wondering if anyone has seen this behaviour before? What could possibly cause this? Why would it have previously ignored the compression settings?
Any help greatly appreciated,