Create an Unsolicited Trigger

About this task

This topic describes how to create an unsolicited trigger for a calculation, and how to set up a dependency list:

Before you begin

If you want to browse for tags while adding a trigger tag, ensure that the Calculation collector is running.


  1. Access Historian Administrator.
  2. Select Tags, and then select the tag to which you want to apply the trigger.
  3. In the Collection section, select Unsolicited from the Collection Type, and specify an interval.
  4. Select Calculation.
  5. Select Add to add a trigger.
    The Insert Function window appears.
  6. In the Trigger Tag field, enter the name of the trigger tag that you want to use in the calculation.
    The wizard automatically populates the Trigger Tag field and updates the Function Preview field, as shown in the following figure:

  7. Select Insert.
    The trigger is added to the Calculation Triggers section.

    In addition, the trigger list appears when using the Insert Function window to build a calculation formula for an event based tag.

  8. Select Update.