alias tags

In rs5000 do you use alias tags for all you inputs and outputs. I am going through a class thru work and the instructor want us to make a whole routine named alias tag configuration. What do you do when setting this up or do you do it a different way.

Does anyone set there programs up using alias tag configuration.

jtashaffer said:

In rs5000 do you use alias tags for all you inputs and outputs. I am going through a class thru work and the instructor want us to make a whole routine named alias tag configuration. What do you do when setting this up or do you do it a different way.

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Alias tag configuration has absolutely nothing to do with logic routines.

Are you sure you are not confusing the usage of alias tags to the I/O tags in the database, against the idea of using a subroutine to "map" the I/O tags to internal tags.

Either way is common, and each has its own benefits.

I like to Alias my Physical I/O when ever i can. One word of caution about Alias Tags: Not every HMI or other connected devices can handle Alias Tags. So before you just Alias everything make sure your connected devices will work it Alias tags properly.

I have recently run into that exact problem. I have been having a issue with my Red Lion G308 not working with Alias tags correctly.

In that case you have to be able to "map" your physical I/O to Internal Tags via a subroutine. The attached file shows how to map your I/O via a subroutine.

Like Daba said there are positives and negatives to both methods.

I am talking about using alias tags for all my inputs and outputs. Which make the logic were the is no fiscal address only in the alias configuration. The logic just becomes tag names. Writing the programming this way just seems harder to troubleshoot in the long run. Or maybe not? I am used to RS500. In the past year I have been getting in to rs5000. Maybe this is the best way. I have seen programs wrote with alias tags and some with out. How does allen bradley and Rockwell sugesst you write programs in 5000. Any ideas would help.

I use alias tags for IO all the time. My alias tag matches the instrument tag followed by a brief description. Eg. LSH455_HighLevel. If alias tags, instrument tags, and electrical drawing tags all match then the technician does not need to be concerned about the actual IO address to troubleshoot.

I also frequently use alias tags for other elements as well, such as a timer .dn bit.

Aliasing is a powerful tool when you learn how to use it.

So it sounds like you don't really know what alias tags are in the 5000 system. That isn't a knock. Alias tags didn't exist in the 500 systems you are familiar with.

What you are referring to is what is generally called "mapping". Alias tags are a different animal and I think most of us here prefer them to mapping.

Rockwell has a bunch of videos on their website to help you get started. Check these out:

**View This One** Video on Creating/Using Alias Tags:
http://www.rockwellautomation.com/r...iasTag.swf&mediaLang=ENU&defaultMediaLang=ENU

Main Page for videos and other tools:
http://www.rockwellautomation.com/r...rated-architecture/tools/overview.page?#/tab4

OG

One reason for creating a subroutine that maps program tags to I/O tags is to buffer your inputs so that you can synchronize it with the program scan. The ControlLogix IO updates are asynchronous to your PLC scan. Unlike the SLC, IO can and does update in the middle of a program scan, You have different tasks operating at different rates. 99% of the time the asynchronous update of inputs doesn't matter, but its possible your instructor wants you learn this technique for that 1% of the time it does matter. Don't confuse buffering your IO with alias tags however.

Thanks for the info. I will check out the videos.