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TN Hist228 Managing Wonderware Historian storage settings

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Wonderware Historian stores historical data to the hard drive of a computer.  Based on the setup of your system and your data requirements you may want to adjust where this is stored, how long it is stored, and how much space can be used.


  • Author: Dillon Perera
  • Published: 09/22/2015
  • Applies to: Wonderware InSQL/Historian 9.0 and higher




The Wonderware Historian has many settings for adjusting how data is stored.  Modification of these settings is done from the Wonderware System Management Console (SMC).


  1. Open the SMC by going to Start > Programs > Wonderware > System Management Console.
  2. Expand the Historian group until you see the server you are interested in.
  3. Expand the Configuration Editor section, and go to Storage > Storage Locations.
  4. On the right, the four possible storage types and their settings will be shown.
  5. The Circular location is where all data is stored by default.  By double clicking on the locations you can see the following settings which can be changed:
    1. Path: This is the path where the historical data files (History Blocks) will be stored.  Note: If you change this, and already have historical data, you will need to manually move your data to the new location.
      Default value:
      1. For InSQL 9.0 and older - C:\InSQL
      2. For Historian 10.0 and newer - C:\Historian 
    2. Deletion Threshold: This is the minimum amount of disk space that must be available on the hard drive before the Historian will attempt to delete or move data from this storage location.  If the deletion threshold is reached, the history blocks will be deleted in a First-In-First-Out (FIFO) manner, removing the oldest data first.  
      You will want this value to be at least 1.5 to 3 times the average size of your daily history blocks.  If space is not an issue, you would ideally want to keep the deletion threshold at a minimum of 1024MB (1GB) in size, to allow for storage needs of other software and the OS.
      Default value: 1024MB (1GB)
      1. Ex #1: If you store 10MB of data daily, at minimum the deletion threshold should be set to 15MB to 30MB.  If space is not an issue, you would leave this value at 1024MB.
      2. Ex #2: If you store 500MB of data daily, at minimum the deletion threshold should be set to 1500MB to 3000MB.
    3. Maximum Size: This setting is used to limit the amount of disk space used by the Historian, before data is deleted or moved.  This setting is useful if you have other software which uses the hard drive, setting a maximum allocation allowed for the Historian software.  By default this value is set to 0MB, meaning that it can use as much space as is available (until the deletion threshold is reached).
      Default value: 0MB, meaning this setting is disabled and maximum size restriction will not be used.
    4. Maximum Age: This setting is used to automatically delete data that is older than a certain number of days.
      Default value: 0 days, meaning this setting is disabled and maximum age restriction will not be used.
  6. If any changes are made, you will need to commit your changes, and then restart the historian.