3 Replies Latest reply on Feb 8, 2018 3:21 PM by sraposo

    AF Analyses - Event triggered backfill does not work.

    Hobbe

      Hi!

       

      I am about to recalculate a single tag. I want to remove all the "0" zero values.

      Therefore i need to have a event triggered calculation.

      It is not possible to check the checkbox.

       

      //Magnus Holmbom

       

        • Re: AF Analyses - Event triggered backfill does not work.
          sraposo

          Hi Magnus,

           

          This analysis is a circular reference (perpetual triggering) if configured as Event Triggered.

           

          I also don't understand how this analysis has been working in the pass or what it could be used for. Do you have something else writing to the input attribute (PK002-05-854 MW) ?

           

          Thanks,

          Seb

          • Re: AF Analyses - Event triggered backfill does not work.
            Shane318

            Hi Magnus,

             

            Sebastien is correct in that you won't be able to write back to the same PI Point if it is part of the analysis.

             

            One way I do filtering is to create a new PI point as the output from the analysis, give it a similar name to the original PI Point but add a suffix to indicate that it is the filtered version.

             

            For example:

             

            'PK002-05-854 MW' is your input tag and 'PK002-05-854_filtered' is the mapped Output Attribute/PI Point.

             

            This uses an additional PI Point but as part of the analysis it is a necessary step for our data integrity.

             

            Regards,

            Shane

            1 of 1 people found this helpful
              • Re: AF Analyses - Event triggered backfill does not work.
                sraposo

                Hi,

                 

                I think that's the only way to do this. We don't recommend having the analysis service output to a PI Point that is being written to by another application (interface). One of the reasons is that the analysis uses cached values when it can to run it's calculations. Consequently values written by another application could be missed.

                 

                Hope this clears things up,

                Seb