Hello Letícia,
The default configuration for openHistorian includes an historian instance by the name of PPA, which you can see by navigating to “Outputs > Historian Instances” in the openHistorian Manager. The connection string for the PPA adapter determines both the directory to which files are written and the maximum age of the data in the archive. By default, the connection string is empty, and the historian instance will keep all data indefinitely in the C:\Program Files\openHistorian\Archive folder.
Keep in mind that the Historian Instances page is one of our older screens and so it doesn’t display the list of connection string parameters like the custom adapter screens do. To configure the connection string, I recommend that you navigate to “Outputs > Manage Custom Outputs”, click the Add New button, and then select openHistorian 2.0 (Local) from the Type dropdown. You can configure the connection string there, then copy/paste it to the Historian Instances screen.
The relevant connection string parameters are ArchiveDirectories, WorkingDirectory, and MaximumArchiveDays.
Thanks,
Stephen