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PI AF Analysis not executing properly?

Question asked by Andrius on Aug 29, 2017
Latest reply on Oct 30, 2017 by jhim

I have a setup involving multiple analyses. Each of them generates value 0 (normal) or 1 (alert). the results of analyses are mapped to the attributes and historized in the tags. On top of that, i have aggregated analysis which adds the values together:

TagMax('EventDef:78|Status','*'-('EventDef:102|Duration' * 60),'*')+TagMax('EventDef:81|Status','*'-('EventDef:102|Duration' * 60),'*')+TagMax('EventDef:79|Status','*'-('EventDef:102|Duration' * 60),'*')+TagMax('EventDef:83|Status','*'-('EventDef:102|Duration' * 60),'*')+TagMax('EventDef:90|Status','*'-('EventDef:102|Duration' * 60),'*')+TagMax('.\Inventories|EventDef:295|Status','*'-('EventDef:102|Duration' * 60),'*')

 

Where 'EventDef:102|Duration' is the attribute containing number of minutes. The goal is to check how many alerts i have within the certain duration. The aggregated analysis is setup as periodic alert to be calculated every minute. The problem is the result sometimes is not what i'm expecting. The chart below shows the aggregated alert (top blue line) and all the alerts comprising it. The Duration in this particular case is 10 minutes. As in this particular, time (8/28 15:50), only 4 of the base alerts are active, yet the tag responsible for historical storage shows value of 6.

The tag name is pretty unique and unlikely is updated by any other place.

Any suggestion what to look at?

 

Trend data:

Validations check:

MonitoredTag - original expression

Variable1 - same expression as in MonitoredTag but passing specific time for debugging

Variable2-Variable7 breakdown of expression members at specific time

Variable8 - value of MonitoredTag retrieved at the particular time.

If all works Variable1 and Variable 8 should always be equal.

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