The Trigger dialog box opens when you click the Add button on the Triggers tab of the Alarm Setup editor.
The Trigger dialog box has the following columns:
Type the tag name or expression associated with the connection. If a tag or expression was selected, it is shown here. You can use analog, digital, and array tags to generate alarms.
Click this button to open the Tag Browser and select a tag instead of typing the tag name in the Tag or expression column.
Click this button to open the Expression Editor and create an expression instead of typing the expression in the Tag or expression column.