OPC Alarms/Events Servers (AE Servers)
AE servers can record values from different data sources, evaluate it, and decide whether an event occurred. An SAP R/3 System can use SAP ODA to subscribe to certain events. The AE server informs the SAP R/3 System that an event occurred, for example, that the temperature has risen above a certain limit.
See also:
Event SubscriptionFilter Criteria
AE servers can provide a number of different events but not all events are interesting for the OPC client. To reduce the number of events to be reported, you can define filter criteria in Customizing for the SAP R/3 System.
The following filter criteria are available:
Event Areas
To arrange events topographically, they are structured in event areas. An event area comprises the namespace in which the events may occur and that can be set up in the AE server. The nodes of the event areas indicate the areas in which events may occur. The leaves represent the sources from which the event information comes (for example, machine). Several events (for example, monitoring the temperature value and temperature sensor) can be defined at a source.
The following example shows the event area Production building #1. The next nodes represent the production lines.
Event Types
To arrange events in a logical structure, they are divided into event types. The following event types are distinguished:
These event types inform the system that an event has occurred (for example, a device failure). The event message contains general information such as the event time, event type, event severity, event category, event source, and the event text (see below).
Beside the information contained in simple events, this event type also contains the actor ID, that identifies, for example, the batch number or the person who triggered the OPC event.
With this event type, it is defined in the OPC server under which conditions an event is to be triggered. This is defined using conditions and its subconditions. The subconditions can describe a reason (for example, pressing a button) or several reasons (for example, value is above or below a limit) for an event. By activating and deactivating the subconditions, you control which events the OPC server sends to the SAP R/3 System. In addition, the OPC server can request an acknowledgement of the reported events by the SAP R/3 System.
Example:
The condition-related event "Door" has the condition "Contact" and the subcondition "Opening Door".
Events of the type Condition-related can contain conditions and subconditions that can be activated and deactivated. AE servers only report those events that match the activated subconditions.
Event Category
The event types are again subdivided into event categories. Examples of event categories would be, for example, device error and system error.
Event Severity
You can assign a severity from 1 (low) to 1000 (high) to every event.
Example of the Filter Criteria for Event Types
