Collect Data for an Indirect Variable

Before you begin

  1. Add or ensure there is a collector instance which you want to collect data for the variable.
  2. Add the tag that you want to map with the variable.

About this task

To collect data of an indirect variable, you must associate the variable with a collector instance and an existing Historian tag. The values for the variable are then collected by the collector instance and stored in Historian.
Important:
  • If the name of a tag associated with a variable in a model contains a period (.), you cannot import the tag while importing the model into a Historian system.
  • If you want to later delete the tag, first remove the mapping between the tag and the variable.

Procedure

  1. Access Configuration Hub.
  2. In the NAVIGATION section, under the Configuration Hub plugin for Historian, select Model. Alternatively, you can select Systems, and then in the row containing the system in which you want to create a model, select , and then select Browse Model.
    The Model section appears.
  3. Under Object Instances, expand the object instance, expand Variables, and then select the variable whose data you want to collect.
    The details of the variable appear in the DETAILS section.
    Note: If the DETAILS section does not appear, in the upper-right corner of the page, select , and then select DETAILS.
  4. In the DETAILS section, in the Tag Name field, select .
    The Tag Selection: <variable name> window appears.
  5. Select Search to search for tags.
  6. Enter the search criteria, and then select Search. You can enter a name or a value partially or use the wildcard character asterisk (*). You can add more search criteria by selecting Add Attribute.
    The list of tags are filtered based on the search criteria.
  7. Select the collector tag that you want to map with the variable, and then select Apply.
  8. In the upper-left corner of the page, select Save.

    You can choose any of the following options provided while mapping the indirect variable with an existing Historian tag to save in Historian with or without the model hierarchy.

    Table 1.
    Field Description
    Use as is Choosing this option will not update the Historian tag name. Mapping Information will be saved only in model database. Mapping information won’t be available with Historian (when you export and try to trend with trending tools like Operations Hub, you will not be able to trend as they are connected to Historian Database).
    Create Alias

    Choosing this option creates an alias of Historian tag mapped with indirect variable.

    This option will save the model tag both in the model database and Historian database as an alias. When you export the model, you will be able to trend and see the data. (This is the default option.)
    Rename Permanently Choosing this option will permanently rename the Historian tag mapped with the model indirect variable and removes the existing tag. So, there will be chance that existing trends using this Historian tag might have impact.