As explained in the previous section, you are able to prevent tags from loading at startup according to their Area property; additionally, you can filter alarm tags so that specific alarms load on specific workstations. The typical application for this functionality is when you have a remote application installation that has one common configuration for all workstations, but on some machines you wish to see a subset of the alarms (for example, if you wished to restrict alarms to specific geographical areas). Alarm area filtering restricts the alarm displays and sounds to only those areas that have been enabled for the relevant machine.
Just as with the [AREAS] section, the area that is being filtered is the normal Area property of the alarm tag. Like ordinary area filtering which enables you to specify which tags to load on which machines, alarm area filtering controls the areas for which alarms are enabled.
The section to use when filtering alarm areas is the [ALARM_MANAGER] section. An example of the syntax for alarm area filtering in a workstation.ini file is displayed below:
[Alarm_Manager]
AlarmArea = Station1
AlarmArea = Station2
The result of the above example is that only alarms with "Station1" or "Station2" configured as their Area property will be loaded on this workstation.
Alarm area filtering supports the asterisk (*) wild card. For example, you may specify:
[Alarm_Manager]
AlarmArea = area*
Rather than:
[Alarm_Manager]
AlarmArea = area1
AlarmArea = area2
AlarmArea = area3
And the same effect would be achieved – only alarms whose area begins with "area" will be loaded on this workstation.
Note: As you can see from the above examples, alarm area filtering works by specifying those alarm tags you wish to load by listing their areas. (Whereas tag area filtering (see Config.ini [AREAS] Section Variables) works by specifying whether or not you wish a tag to load by listing areas and then indicating a value of 0 (load) or 1 (do not load).)