About Alarms and Events

Using Configuration Hub, you can manage alarms and events data from any OPC-compliant alarms and events server.

Note: The Alarm Archiver must be available and running to access this feature.

Alarms: Alarms are generally defined as tags going into an abnormal condition. For example, you can set an alarm on a boiler when it reaches a specified temperature. Alarms usually have a well-defined life cycle, which is defined by the individual data sources from which the alarms data is collected. They enter an alarm state, are generally acknowledged, then return to normal.

To collect alarms and events data, you can use any of the following collectors:

iFIX Alarms and Events collector
OPC Classic Alarms and Events collector

Historian handles alarm data in two ways. You can view the entire Alarm as a single record that contains all information about the alarm, or you can view the Alarm History, which shows the transitions of the alarm as individual records.

Events: Events are generally defined as activities in a system that occur once only. For example, a user logging on to a device is an event. When viewing this data in Historian, each event is returned as a record.