Is it possible to have multiple tagnames when suing Tagtot or Findeq Syntax eg: Tagtot ('FlowA' +'FlowB', '-1h', '*',85) or Findeq ('FlowA' +'FlowB','*','*-1440h',100)
according to the syntax underlined in the following links, I would say that now it is not possible:
TagTot(attname, starttime, endtime [, toUnit] [, pctgood])
FindEq(attname, starttime, endtime, x)
OK, noted with Thanks
What would be Your intension with using 'multiple' tagnames in expression functions??
Perhaps: Tagtot ('FlowA', '-1h', '*',85) + Tagtot ('FlowB', '-1h', '*',85) ???
Or is it possible to have a tagto with equation on the Tagname? e.g.
TagTot( 0.0002* 'GKA.FPS.A03-11.28FI021.PV'^2, '-440h','*')
No, unfortunately it's not possible that way. The first argument of Tagtot() must be a tagname. : (
You can easily deal with the constants out front using some syntax like this, however you should handle the squaring in another tag. Eventually, you'd end up with something like this. However, this becomes fairly trivial with Analytics as you are able to do these intermediate calculations with variable expressions until you reach your final expression (the integration) to historize.
0.0002*TagTot(GKA.FPS.A03, '-440h','*') - 11.28*TagTot(SquaredResult, '-440h','*')
My laziest idea is to create a PI PE tag with the expression required by your equation to calculate the 'corrected measurement'.
Then You can use the Tagtot('Corrected_Tag', '*-440h','*') for the time-integration.
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