About this task
When backing up your Historian archives, any alarms that have a life cycle that overlaps the data archive being backed up will be included. This means that an alarm with a long life cycle can be included up in multiple backups. For example, say the following alarm and archive dates were the following: Alarm/Data Archive | Start Time | End Time |
---|
Alarm1 | 09/02/2004 | 09/06/2004 |
Archive1 | 09/01/2004 | 09/03/2004 |
Archive2 | 09/03/2004 | 09/04/2004 |
Archive3 | 09/04/2004 | 09/06/2004 |
If any or all of these archives are backed up, Alarm1 will go into the backup for each one. When the archives are restored, Historian will analyze the included alarm data and, if the data is already in the Historian archive, is intelligent enough to know it already has the alarm. Use the following procedure to change alarm timestamp checking.