Specifications

Allen-Bradley ControlLogix Ethernet Driver Help
Automatic Tag Database Generation
The Allen-Bradley ControlLogix Ethernet Driver can be configured to automatically generate a list of server tags
within the server that correspond to device-specific data. The automatically generated tags are based on the
Logix tags defined in the Logix device, and can be browsed from the OPC client. Logix tags can be atomic or
structured. Structure and array tags can quickly increase the number of tags imported (and therefore the
number of tags available in the server).
Note: ENI/DH+, ControlNet Gateway, and MicroLogix 1100 models do not support automatic tag database
generation: only ENI ControlLogix, CompactLogix, and FlexLogix models do.
Atomic Tag -> one-to-one -> Server Tag
Structure Tag -> one-to-many -> Server Tags
Array Tag -> one-to-many> -> Server Tags
Note: For more information on the Database Creation settings, refer to the server help file.
Tag Hierarchy
The server tags created by automatic tag generation can follow one of two hierarchies: Expanded or Condensed.
To enable this functionality, make sure "Allow Automatically Generated Subgroups" is enabled in Device
Properties. The default setting is Expanded Mode.
Expanded Mode
In Expanded Mode, the server tags created by automatic tag generation follow a group/tag hierarchy consistent
with the tag hierarchy in RSLogix 5000. Groups are created for every segment preceding the period as in
Condensed Mode, but are also created in logical groupings. Groups created include the following:
l Global (controller) scope
l Program scope
l Structures and substructures
l Arrays
Note: Groups are not created for .bit addresses.
The root level groups (or subgroup levels of the group specified in "Add generated tags to the following group")
are "Prgm_<program name>" and "Global". Each program in the controller has its own "Prgm_<program
name>" group. The driver recognizes this as the first group level.
Basic Global Tags (or non-structure, non-array tags) are placed under the Global group; basic Program tags are
placed under their respective program group. Each structure and array tag is provided in its own subgroup of
the parent group. By organizing the data in this fashion, the server's tag view mimics RSLogix5000.
The name of the structure/array subgroup also provides a description of the structure/array. For instance, an
array tag1[1,6] defined in the controller would have a subgroup name "tag1_x_y"; x signifies dimension 1
exists, and y signifies dimension 2 exists. The tags within an array subgroup are all the elements of that array
(unless explicitly limited). The tags within a structure subgroup are the structure members themselves. If a
structure contains an array, an array subgroup of the structure group is created as well.
With a complex project, the tag hierarchy can require a number of group levels. The maximum number of group
levels created by automatic tag generation is seven. This does not include the group specified in "Add generated
tags to the following group". When more than seven levels are required, the tags are placed in the seventh group
(causing the hierarchy to plateau).
Array Tags
A group is created for each array that contains the array's elements. Group names have the notation: <array
name>_x_y_z where:
x_y_z = 3 dimensional array
x_y = 2 dimensional array
x = 1 dimensional array
Array tags have the notation: <tag element>_XXXXX_YYYYY_ZZZZZ. For example, element tag1[12,2,987]
would have the tag name "tag1_12_2_987".
Simple Example
www. kepware.com
90