RSView Supervisory Edition Installation Guide

alarm’s time stamp. Because alarms are scanned in the background,
alarms that are generated rapidly might appear out of sequence in
RSView, because they might all be scanned at the same time, and
therefore given the same time stamp. If the sequence in which alarms
are generated is important, you might want to record accurate time
stamps for the alarms by buffering the alarms in the PLC, and then
using alarm events to record them with accurate time stamps in
RSView.
You can also use alarm events to provide a tag with more than eight
thresholds.
To create an alarm event, use the AlarmEvent command.
How event-based alarms work
Alarm events let you create alarms without setting up tags in the tag
database. Event-based alarms work just like tag-based alarms. They
appear in alarm summaries, they can be used with alarm system tags,
and they can be logged to disk or printer.
You can filter event-based alarms the same way you filter tag-based
alarms in alarm summaries. You can acknowledge event-based alarms,
either individually, or with wildcard characters, using the Acknowledge
command. You cannot suppress event-based alarms.
As with tag-based alarms, you can use alarm events with alarm
functions in expressions.
You can time-stamp event-based alarms with the current time, or by
specifying a date and time either in RSView or in alarm-detection
algorithms you create for the application.
Alarm events are not processed until the AlarmOn command is issued,
and alarm events are no longer processed after the AlarmOff
command is issued.
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