How to Set-up Redundant Logging with the OPC DA Collector
Redundant Logging allows the same data to get sent from two different logging sessions to one historian. Redundant Logging ensures that data is never lost when one logging session stops for whatever reason. Redundant Logging is accomplished by creating multiple logging sessions that log to the same historian. Read this article to learn how to create a logging session.
Select a logging session tab towards the top of the screen.
Write the data to a historian by typing in the name of the machine that has the historian installed on it (historian machine).
Apply the changes and start the logging session
Select and/or create another logging session, and repeat steps two and three.
Many logging sessions from many machines can be logged to one historian.
The Historian differentiates redundant values from good values using the tag's timestamp, values with identical timestamps are not logged. Make sure the 'Normalization Time' is set to seconds '00:00:01' and not subseconds. Learn more about Normalization time.