Alarm Disturbance table

The Alarm Disturbance (almdisturbance) records are used to suppress alarms below a set severity level. Almdisturbance records are located in the Alarm Disturbance (almdisturbance) table and are created and edited using the almdisturbance Row Edit dialog box.

In alarm disturbance mode, the system suppresses alarms whose severity level is lower than or equal to a configured severity. This mode of suppression applies to all types of alarm, such as state-based alarms and command failure alarms.

Return-to-normal state alarms are typically configured with low severity levels. Instead of updating the alarm summary to show that the alarm has returned to the normal state, alarm disturbance mode purges the alarm from the alarm summary.

Alarm processing requires considerable resources, and alarm disturbance mode helps reduce the alarm processing required when the system is inundated with alarms. By suppressing lower-priority alarms, it also reduces the number of alarms submitted to the Controller.

Each almdisturbance record allows you to configure the maximum alarm severity that the system will suppress. This configuration takes effect without the need to restart RealTime services.

The Controller has the ability to enable or disable alarm disturbance mode through easy eXtended Operator Station (ezXOS) (refer to the AVEVA Enterprise SCADA HMI Controller documentation). A Developer can also write an application to automatically enable or disable alarm disturbance mode. Enabling or disabling alarm disturbance mode in one system does not affect the mode setting in another system.

When a Controller disables alarm disturbance mode, the system regenerates suppressed state-based alarms, such as those resulting from data krunch; however, other low priority alarms, such as command failure alarms and system alarms, are not regenerated. The system reevaluates non-inhibited alarm records of analog, status, and rate points for which no alarm record exists in the alarm summary.