Applies To:
  • CitectSCADA v7.x
  • VijeoCitect v7.x

Summary:
 I set my [Alarm]SummaryLength to a high value (eg: 100,000).
However, when I trigger 50,000 alarms, I am able to display more than 200,000 events in my alarm summary.
Where are these extra alarm records coming from?

Solution:
The [Alarm]SummaryLength parameter applies to the alarm server side.
The alarm server is able to capture and keep in memory up to 2 billion records.

The problem here is “only” related to an alarm client issue. When an alarm page is displayed, the alarm client is not currently able to handle more than 32767 alarm records.
As long as less than 32767 alarms are received by the alarm client, then the alarm pages will display a valid number of records.
However, as soon as the client request is resulting in more than 32767 records, then the display in result will contain extra “ghost” alarm entries.

This can be relatively easily worked around by applying some filtering on the alarm page. The CSV_Example provides examples of alarm filters.
When a client applies a filter, the filter will be applied to the query sent to the alarm server which, in return, will therefore send fewer records to the alarm client.

Keywords:
 Alarmdsp, 32767, SummaryTimeout

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