Local Historian Plug-In for KEPServerEX

The Local Historian Plug-In moves data collection, storage, and access closer to the data source to prevent data loss and improve operational efficiency via open access and a single product solution. By plugging into the KEPServerEX communications platform, the Local Historian can connect to any device and add devices in real-time without operational downtime. Its plug-in architecture simplifies configuration, provides flexibility, and makes the information accessible across OPC HDA (an open standard).


Local Historian Plug-In Manual (PDF)
Local Historian Plug-In Datasheet (PDF)

Plug-In Driver Features:

  • Collects data consisting of a value, quality, and timestamp from any data source in the server (such as drivers, plug-ins, or system tags)
  • Collects from both static and dynamic server tags
  • Supports persistence to a volume on the local machine (which can be a fixed drive or removable media)
  • Supports access to historical data via OPC HDA 1.20
  • Supports data timestamps with one millisecond resolution
  • Supports configurable data collection scan rates as frequent as 10 milliseconds
  • Supports collection deadband
  • Has a configurable data retention policy
  • Imports historical data that has been backed up and removed from active use
  • Has a built-in historical data viewer for quick troubleshooting
  • Supports tiered licensing for up to 10,000 tags

Supported Devices:

  • All devices supported by KEPServerEX


  • OPC HDA 1.20 client access
    • Supported IOPCHDA_Server Interface Functions:
      • GetAggregates
      • GetHistorianStatus
      • GetItemAttributes
      • GetItemHandles
      • ReleaseItemHandles
      • ValidateItemIDs
      • CreateBrowse (except filtering)
    • Supported IOPCHDA_SyncRead Interface Functions:
      • ReadAttribute
      • ReadProcessed (AVERAGE only)
      • ReadRaw
      • *The supported ReadProcessed aggregate is AVERAGE.
    • Supported IOPCHDA_Browser Interface Functions:
      • GetEnum
      • ChangeBrowsePosition
      • GetItemID
      • GetBranchPosition