i have one tag that tag need to get values cumulatively and reset at 1st of month.
could any one help me in the same
Awaiting for your response
Have you consider using PI Totalizers? There is an interesting video comparing PI Performance Equation with PI Totalizers on Youtube.
Today my choice would be Asset Based Analytics. Please have a look to this learning videos at OSIsoft's Learning Channel at Youtube.
PI Performance Equations syntax is used with Asset Based Analytics and because of Intellisense the help provided for the functions usually does not require consulting additional documentation but if needed, PI Performance Equation Reference is a good choice. PEReference.chm can be found at %PIHOME%\Help folder on almost every machine with PI installed.
TagTot() can be used for a time-weighted total. There's no function for the event weighted total but you can easily build it by using TagMean() for the event weighted average and multiply with EventCount().
With Bom('*') you refer to Begin of month what I suggest as the start-time. For the end-time you would refer the current time with '*'.
Further I suggest using Event-Triggered scheduling with your tag to be totalized as input.
You've posted your question at PI System Web API forum. Please allow me moving it to PI System Integration forum.
Because of know issue 19811OSI8 - Totalizer and Alarm Subsystems ignore source tag events queued as a result of persistent Update Manager signups and at least one reboot per month required by Windows update, I do not recommend using PI Totalizer subsystem for calculations that run longer than a 24 hours.
okay you can move it to respective forum
can anyone help me with the syntax to get cumulative values and it should reset on 1st of month.
1. tag1=tag2+tag3 is my existing one, please add correct syntax for that,
Awaiting for response and solutions
Thanks in Advance
With your expression you are summing up current (snapshot) values. Is this the kind of accumulation you are interested in or do you intend building a monthly total of tag2 and tag3?
If you are after a total, is it supposed to be time-weighted or event-weighted?
What calculation engine have you decided for (PI Performance Equation, PI Totalizer or Asset Based Analytics)?
It looks to me as if you decided for either PI Performance Equation or Asset Based Analytics.
The syntax for a time-weighted total of a single tag would look like this: TagTot('tag2',Bom('*'),'*')
With regards to the example you provided this could be tag1=TagTot('tag2',Bom('*'),'*')+TagTot('tag3',Bom('*'),'*') but I am not sure, if I properly understand what you are looking for.
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