Rockwell Automation FactoryTalk View Site Edition Users Guide - Manual (Page 191)

10 • W ORKING WITH TAGS
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Relative references
Relative references point at a tag relative to the current server or area. A relative reference
to a tag called Extractor is simply the tag’s name:
Extractor
When a relative reference is used, FactoryTalk View assumes that the tag is located in the
current area.
Use relative references, for example, to re-use component names in a network distributed
application for a plant that has identical production lines.
The application might contain different areas to represent each production line; however,
within each area, the same names would be used for application components such as
graphic displays.
The home area
In network distributed applications, the home area is the area, in which an application
component (for example, a tag or graphic display) is located.
When you refer to an application component without specifying the area, FactoryTalk
View SE uses the home area to locate the component.
For example, if you create a graphic display in the Cooling area, and add a relative
reference to a tag (for example, FanStart), FactoryTalk View SE looks for the tag in the
home area of the graphic display (Cooling).
If the tag cannot be found in an HMI server or a data server in the display’s home area, an
error is logged when the display is run.
Finding the home area in the Tag Browser
In the Tag Browser, the home area in a network distributed application is shown in bold
type, as shown in the following illustration.