Delete Tags

Historian allows you to delete and permanently delete tags. When a tag is deleted, it is removed from the tag database, but all data for that tag is retained in the archive and the tag name cannot be re-used. Since the tag data is still available from the archive, you can still reference that tag from within a calculation formula, for example, or by using the Excel Add-In.

When a tag is permanently deleted, all the data for that tag is removed from the archive and the tag name is available for reuse. For more information, see Permanently Deleting Tags.

By default, the On-line Tag Configuration Changes option is enabled, which allows a tag to stop and restart data collection without restarting the collector. If you disable the On-line Tag Configuration Changes option, any changes you make to the tags do not affect collection until after you restart the collector. To enable or disable the On-line Tag Configuration Changes option, click the Advanced tab of the Collector Maintenance screen. To restart a collector, stop and start the collector service or executable.

Restarting the collector stops and restarts the tag(s) collection and may record bad data samples to the collection. All the collector configuration changes done within a 30 second time frame are batched up together. To collect the modified data faster, update/modify a small set of tags at a time. If the modified tags get zero bad markers and available runtime values at the same time, then precedence is given to available runtime values instead of zero bad markers.