About Historian Data Collectors

Many data collectors bring data into the Historian server, as listed in Supported Windows Versions for Historian Collectors.

Since installation, maintenance, and troubleshooting from a Historian perspective are essentially the same for all collectors other than the File collector, this chapter summarizes the characteristics of each and highlights their differences. It also provides a detailed description for the File collector, since it differs from the other types of collectors.

A data collector gathers data from a data source on a schedule or event basis, processes it, and forwards it to the Historian server for archiving. The following image shows the data flow in a typical Historian system from a data source to the archive.

Data collectors use a specific data acquisition interface that match the data source type, such as iFIX Easy Data Access (EDA) or OPC 1.0 or 2.0 (Object Linking and Embedding for Process Control). For more information, see Supported Acquisition Interfaces. The Simulation collector generates random numeric and string data. The File collector reads data from text files.

The following table provides information on whether each collector is toolkit-based and whether is consumes a CAL.
Collector Name Is Toolkit-Based? Consumes a CAL?
The Calculation collector No Yes
The Cygnet collector Yes Yes
The File collector No No
The iFIX Alarms and Events collector collector No No
The iFIX collector No No
The MQTT collector Yes Yes
The ODBC collector Yes Yes
The OPC Classic Alarms and Events collector No No
The OPC Classic HDA collector Yes Yes
The OPC UA DA collector Yes Yes
Th OPC UA Data Access (DA) collector No No
The OSI PI collector No No
The Server-to-Server collector No Yes
The Server-to-Server distributor No Yes
The Simulation collector No No
The Windows Performance collector Yes Yes
The Wonderware collector Yes Yes
  • When failover occurs from a primary collector to a secondary collector (or vice versa), there will be some data loss as the collector tries to connect to the source to fetch the data.