Access to alarms and events

To receive alarms and events, an OPC UA client on the TwinCAT OPC UA Server must log in to one of the configured ConditionControllers. The client then receives the alarms and events for symbols that have been configured in this ConditionController.

The following example shows how you can use the UA Expert software from Unified Automation to subscribe to a ConditionController in order to receive alarms and events from it.

After you have started the UA Expert and established a connection to the TwinCAT OPC UA Server, add a new document view of the type "Event View" to your working area.

In the address space of the server, you will find all configured ConditionControllers below the "A&C" node. You can now drag and drop a ConditionController from the "Event View" working area to subscribe to it. The alarms and events for this ConditionController are then displayed in the Event Window.