2 Replies Latest reply on Jun 3, 2010 2:16 PM by gmoffett

    Totalizer and PE Alternatives


      Next dirty Question:


      in my humple opinion ... the totalizer / PE / ACE has a couple of flaws... especally when i comes into the direction of


      A) recalulation (controlled by users not piadmins..)
      B) what happens if the interface is disconnected for a couple of hours,
      C) what happens if pi server is down,


      Has someone created an alternative engine to cover this questions?


      As an example:

      We have a couple of easy calculations (avg,min, max, totals...) which are done in an external dot.net application where the configuration is done in af. (in principal it  summarize values and send it via textfiles to a overlying system and also via ufl back into the pi.)  The goal is to manage approx 7000 calc.


      the solutions for my on the top descriped problems are:


      A) recalculation (the user can (based on af - rights) the date/time of the last calculation set back into the past ... and the "logic" picks up. the same for if the pi server is down..


      B)  if the interface is disconnected the data have  5 hours time to come back, otherwise the timeframe is ignored...


      C) same as A)


      My Question to myself is should the users create calc / total in PE and Totalziers or should the use our logic...


      My Question to you,.. has anyone done something similarly?

        • Re: Totalizer and PE Alternatives

          In an attempt not to hijack your thread...again...I have a similar experience to you on recalculation


          At the time (about 4, 5 years ago) I wrote an application that performed some calculations and it too uses a "last run time" data item to indicate when calculations last ran, and it always calculates forward from that point in time.  In assumes there is some buffering of data from interfaces if PI is down or an interface is down.  It also allows users to "rewind" calculations if they want to alter inputs.  This was built for a specific set of calculations (still a unique set of calculations within that client ) but the principles were lifted to quite a few other applications.  Since then things are getting a lot better with off the shelf calculations/analytics and when running cases/analysis or eventually event frames becomes a 'permanently exposed feature' ()  within AF it will tick some more boxes from my perspective.  Being able to make adjustments to case data and re-run a case is a great option in a lot of scenarios.


          The one part of ACE I would still like to see is a more "business user" friendly method of managing/reviewing/altering calculations, possibly with some workflow & approval steps (especially as we now get WIS on the PI server and AF) - rather than relying on having Visual Studio installed etc...I saw one client's attempt to tackle this, it was quite a good solution that gave business users a sandbox to test calculations before submitting them for production.





          • Re: Totalizer and PE Alternatives



            Thankyou for commenting and providing input, internally we have these documented (and now updated from your input!) as


            1. Recalculation - A) above - User wants to rerun analytics based on changes to the input data
            2. History Recovery - Run analytics for period of time the analytic scheduler was offline
            3. Out of order event processing - Input data for analytics is time stamped prior to events already processed


            B) and C) are scenarios that would appear to fit in with the second and third entries above or would be handled by the normal operation of a scheduler


            Point about user running the recalculation also noted


            As for recalculation today


            - there is the recalculator for Performance Equations


            - ACE supports recalculation