WebAccess supports 99 Alarm Priorities. The Higher the number, the Higher the Priority. Alarm Priority = 0 is no alarming.
The concept of “alarm priority” is that some alarms are more important than others. Alarms can be sorted by alarm priority on the Alarm Summary display to show operators the most important alarms first: on the top of the list.
The higher priority number is considered more important and is listed on the top of the list (i.e. priority 4 is higher than a priority 1). WebAccess provides 99 alarm priorities. Most users select a smaller number to use.
WebAccess also uses the alarm priority to “configure” an alarm. Alarms with a priority equal to zero are not active and cannot be enabled. Alarm Priority equal to zero is No Alarm.
Another consideration in planning Alarm Priority scheme, is that Alarm Priority can be used to filter alarms in the Alarm summary. The idea is that not everyone wants see all alarms in the system. WebAccess provides alarm filtering by priority. Essentially the Alarm Summary ignores alarms for the selected priorities.
The Alarm Priority of High-High alarms must be greater than that of a High alarm if both are configured for the same tag. Similarly, the Alarm Priority of Low-Low Alarms must be greater than the alarm priority of low alarms if both are configured for the same tag. The WebAccess Project Manager (Configuration Tool) will warn for this when trying to save a Tags configuration.
If more than one alarm is in the Alarm State for the same tag, only one alarm is reported. The precedence of alarms for the same tag is
· High-High, Low-Low
· High, Low,
· Rate of Change and
· Deviation.
For example if both High-High, High, Deviation and Rate of Change alarms are all true, only the High-High alarm is reported in the alarm summary and alarm log.