I am still pretty new to PowerShell in general, and have been scrambling to assemble useful code using the OSIsoft.PowerShell library to perform various PI data management tasks. I was really glad when I got this one worked out and decided to share it with you all. This script uses a variation of the OSIsoft.PowerShell library cmdlet "Get-PIExpressionSummary". Developers may want to note you can substitute "Average" for other summary types such as Total, Maximum, Minimum, StdDev, etc.. This tool is a pretty quick and convenient way to generate a bunch of .csv files for a list of tags.


If you are not too familiar with OSIsoft.Powershell I just want to remind you to execute:

  Get-Command -Module OSIsoft.Powershell

to load the OSIsoft.PowerShell library, if you have not already done so, before you try this PowerShell script.


The "source_tags_TEST.txt" file is just a single space list of pi tags like this:





Here it is:


     This PowerShell Script Retrieves interpolated values for a list of PI tags at specific intervals.

     The data is written to separate csv files for each tag. As noted the intervals should be a count

     of intervals between the start and end time. For example every minute for one day would be

     60 minutes x 24 hours = 1440.



# ==========  C O N F I G U R A T I O N S   P E R   R U N  ==========


$sourceFile = "C:\Temp\Source\source_tags_TEST.txt"              #~ Directory and file name for the list of tags

$destinationFolder = "C:\Temp\Destination\"                      #~ Directory where the csv files will be written

$dataStartTime = Get-Date("17-Mar-17 13:00:00")                  #~ Specify data extration start time

$dataEndTime = Get-Date("17-Mar-17 15:00:00")                    #~ Specify data extration end time

$intervals = 120                                                 #~ Needs to be a chosen count of intervals for the time range (i.e. 60 minutes x 2 hours = 120)


#~ Other configurations for generating values and the files:

$times = @($dataStartTime,$dataEndTime)

$suffix = ".csv"


#~ Connect to the target PI Server:

$piConn = Connect-PIDataArchive -PIDataArchiveMachineName $piServerName


#~ Get your pi points one by one and write the csv files:

$piPoints = Get-Content $sourceFile

ForEach($piPoint in $piPoints){

    $expression = "'$($piPoint)'"


   #~ The next line does the heavy lifting:

    $results = Get-PIExpressionSummary -Times $times -Intervals $intervals -SummaryType Average -Basis TimeWeighted -Expression $expression -Connection $piConn


    $myDestinationForData = "$($destinationFolder)$($piPoint)$($suffix)"

    $myStreamWriter = [System.IO.StreamWriter] ($myDestinationForData)

    ForEach ($result in $results){

        $piTime = $result.StartTime.ToString("MM/dd/yyyy HH:mm:ss")

        $comma = ","

        $resultValue = $result.Values["Average"].Value