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Old March 4th, 2013, 03:40 PM   #4
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Originally Posted by Operaghost View Post
I agree with jstolaruk.

You can also open your Find window and under "Limit To" select References to Tag. That will search for where the base tag is being referenced by an alias.

See, that I/O tag wasn't actually being used there. An alias was used there instead. In the 5000 system those are two separate tags. The alias "points" to the original I/O tag for the data, but it is still a separate tag.

The alias tag "knows" it is tied to the base I/O tag, but the I/O tag has no idea that there are aliases pointing to it.

Quite true, but the Cross-Reference tool does show this information.

Consider the situation in the picture attached. I created 2 tags, both aliased to the same input point. I ran the cross-reference on Tag1, and the resulting x-ref listing has "discovered" that the base tag for Tag1 has another tag associated with it, and lists that as well.

realolman's problem is that the BlahBlahBlahSOlenoid25 tag is an alias to the I/O point Local:2:O.Data.7, and a search will NOT find base tags, unless configured as above. The base tag for the alias is displayed on the ladder (if enabled), under the alias tag in blue with <> braces around it. This display is an RSLogix5000 function (i.e. the programming software), and the controller has nothing to do with it.
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Last edited by daba; March 4th, 2013 at 03:46 PM.
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