Alarm faults and alarm quality

Alarms have good or bad quality. Good quality indicates the alarm is functioning correctly. Bad quality indicates there is a problem with the alarm.

The current state may not be detected or accurate. Bad quality occurs from abnormal scenarios, such as a disconnect in the network, or a controller in

Program

mode, or by configuration issues. If the alarm has bad quality due to an abnormal scenario, all conditions of the alarm fault because evaluating or detecting the alarm is not possible. If the alarm has a configuration error, such as invalid limit, only the affected conditions have bad quality. The unaffected conditions have good quality and continue to function. View alarms with bad quality in an

Alarm Manager

only. Quality details appear in the

Details

pane of the Alarm Manager table.

For configuration-related faults, level conditions (HIHI, HI, LO, and LOLO) and ROC conditions (ROC Positive and ROC Negative) are evaluated independently. With the exception of severity, only affected conditions are faulted. If the ROC Positive limit is invalid, only the ROC Positive condition faults. The ROC Negative condition and all level conditions maintain good quality. If the ROC_Period is invalid, both the ROC Positive and ROC Negative conditions fault, but all level conditions maintain good quality. Level condition limits have dependent relationships. The HIHI limit must be greater than HI, HI must be greater than LO, and LO must be greater than LOLO. If any level limit is out of range, all levels fault.

In an

Alarm Manager

, inhibit states from all alarm conditions roll up for a single alarm. If the level or ROC conditions fault for an alarm, the alarm is of bad quality. The conditions that are of good quality continue to function normally and appear in an

Alarm Summary

when they are in the

interesting

state. When the alarm is of bad quality due to an abnormal scenario, all conditions for the alarm are of bad quality.