AnsweredAssumed Answered

Weird values returned from PI Analysis

Question asked by gavin.strack Champion on Oct 5, 2016
Latest reply on Oct 20, 2016 by gavin.strack

Hi PI^2,


I have a weird issue with a PI Analysis. I had set up a rolling 24h average of a value, which is being historised. The value of this rolling average was used in a periodic PI Notifications daily at 8am. This meant that the value in the notification was the 24h average at 8am. This worked perfectly.


I then started to add analytics and other content to this notification. I also changed the 24h so that instead of a rolling 24h average, it would use the 24h average using a start time of 'y+8h' and an end time of 't+8h'. I thought this would be a more robust means of providing the 24h average at 8am daily.


What I have discovered is that occasionally, this value creates a crazy number. If I evaluate the PI Analysis or refresh the Attribute values in PI System Explorer multiple times, I get values like this:


10.34 <refresh> 10.34 <refresh> 10.34 <refresh> 1234.12424345 <refresh> 10.34.   


I've reverted back to the rolling 24h calculation and it still does the same thing.


Anyone else seen this type of problem before?