3 Replies Latest reply on Feb 7, 2019 2:17 PM by TimCarmichael

    Timestamp

    chprzemo

      Hello,

       

      I need find timestamp since when he is present value in TAG. e.g. My TAG gets value 10 for few day, i need find timestamp from past when this TAG it was changed at actual value.

       

      Of course i can find this information in SMT but i need prepare automatic mechanizm for user which do not access to SMT.

       

       

      Thanks,

      Przemek

        • Re: Timestamp
          Vitor_Fernandes

          You can find in PIDatalink, or maybe in a trend at PIVision or ProcessBook

            • Re: Timestamp
              chprzemo

              The best for me will be saving in another PIPoint timestamp last change in TAG because my user use this information in another system and he can not use trend or PIDatalink

                • Re: Timestamp
                  TimCarmichael

                  If I understand the question, you want a tag to hold a timestamp every time another tag value changes.

                  The first step is creating your new tag with a point type of timestamp to hold the value change time.

                   

                  Then, if you are using Performance Equations, a tag with an event source in the extended descriptor:

                  event=<Source Tag>, if '<Source Tag'<> prevval('Source Tag', '*') then '*' else nooutput()

                   

                  If you are using AF Analytics, create an analysis that is event triggered on your source tag:

                  if '<Source Tag'<> prevval('Source Tag', '*') then '*' else nooutput()

                  3 of 3 people found this helpful