800xA 5.1 FP4 how to delete ghost alarms after typical change permanently?
we created a typical with several alarm blocks inside. Some function blocks were installed and running on the system when we changed the typical. Later we implemented some more function blocks with the 'new' typical. Somehow we get alarms from the early installed function blocks after loading (warm) or starting the alarm/event manager. The later installed function blocks are working fine.
To clear the system from old alarms a collegue stopped all alarm/event manager services and deleted the alarm database file. Normally with this work around we can delete old alarms.
For those alarms as described before we failed an we get still this alarms.
You cannot delete a single events but you can delete the particular 800XA events category. The 800XA category ID can only find in the software developer login not in the normal administrator login . In software developer login, there will be more alternative will be accessible.
So you can request the event category deletion procedure to support line.
Function Block = AC 800M?
AC 800M Connect support "OPC AE Refresh" = you must purge the alarm from the OPC server/controller to get rid of lingering alarms. As long as the alarm remain in the controller or OPC AE server of AC 800M, the 800xA HMI will "refresh" them back soon after you have "deleted" them.
By the way, "Delete" in 800xA HMI alarm list is "superficial" and only takes place in Alarm Manager (which by the way is RAM based, no file on disk to delete...). Restart/refresh will bring the alarms back to the HMI as soon as you perform a download or suffer a failover between Event Collectors.
-> Use 3rd party OPC AE client (e.g. MrCrilfe.exe) to verify that the AC 800M OPC Server is not having the old alarms. If they still exist there; you can try to restart the AC 800M OPC server service, but if the alarms come back, a cold start of the controller is likely required.
Events are permanently stored by the 800xA Event Storage service (until storage wraps, default 10.000 events, individually per category). You cannot delete a category alone (it would allow tampering with e.g. audit trail...). A cold start of the Event Storage service is required. Contrary to most other 800xA services, a cold start of the Event Storage service require you to delete and recreate the service providers from the Service Structure, as well as removing the data files on disk below \OperateITData\Event Storage\...