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Rockwell Automation Publication 1769-UM021G-EN-P - October 2015
Chapter 10
Develop Applications
There are several guidelines for creating and configuring parameters and local
tags for optimal task and program execution. For more information, see the
Logix5000 Controllers and I/O Tag Data Programming Manual, publication
Extended Properties
The Extended Properties feature lets you define more information, such as limits,
engineering units, or state identifiers, for various components within your
controller project.
Pass-through behavior is the ability to assign extended properties at a higher level
of a structure or Add-On Instruction and have that extended property
automatically available for all members. Pass-through behavior is available for
descriptions, state identifiers, and engineering units and you can configure it.
Configure pass-through behavior on the Project tab of the Controller Properties
dialog box. If you choose not to show pass-through properties, only extended
properties that have been configured for a given component are displayed.
Pass-through behavior is
not
available for limits. When an instance of a tag is
created, if limits are associated with the data type, the instance is copied.
You must know which tags have limits that are associated with them as there is no
indication in the tag browser that extended properties are defined for a tag. If,
however, you try to use extended properties that have not been defined for a tag,
the editors show a visual indication and the routine does not verify.
Component
Extended Properties
Tag
In the Tag Editor, add extended properties to a tag.
User-defined data type
In the Data Type Editor, add extended properties to data types.
Add-On Instructions
In the properties that are associated with the Add-On Instruction definition, add
extended properties to Add-On Instructions.
