3 Replies Latest reply on Oct 8, 2018 12:48 PM by Rick Davin

    Attributes referencing in PI AF

    Archit

      Hi,

       

      I want to use a child attribute that referencing a child child attribute referencing a pi point (giving value in days) to a parent attribute that references a pi point to generate average of the pi point.

       

      The average in days should come from that value.

        • Re: Attributes referencing in PI AF
          Rick Davin

          Hi Archit,

           

          Could you include an image of the current structure with the attributes in question?  I am having difficulty trying to picture precisely what you want.

           

          The UOM is not pertinent in this discussion.  Suffice to say that you will have some attribute using the PI Point data reference that reads from a numeric tag, presumably Float32 (Single), and the attribute would have a DefaultUOM.

           

          For now, let's use generic names for the attributes:

           

          • ParentAttr
            • ChildAttr
              • GrandChildAttr

           

          ParentAttr will be a type Single with PI Point DR configured to produce a summary?  I am curious as to what Relative Time you are using for the Average since it does require a time span context.

           

          Will the ChildAttr or GrandChildAttr use the PI Point DR to fetch the archive values for the tag?  For the other attribute that isn't a PI Point, what is its purpose?  Will it be a string used for naming?

          • Re: Attributes referencing in PI AF
            Archit

            Dear Rick,

             

            My query is as below:

             

            I have to calculate average of a pi point in an AF attribute. However the time span required to calculate the average should also come from another pi point which gives data in days.