define digital rung in RSLogix5000

Hi;
When I write a digital rung in RSLogix5000, I define the tag style as binary, and data type as bool, is this correct? or there is another opinion.

Thank you

Other option:

using DINT data type.

e.g. Process_Run_Current_State.0

when setting up a BOOL tag, many (most?) people would prefer to set the “style” for “decimal” rather than for “binary” ... the “style” setting basically just determines how the tag is displayed on the screen ... think of it as something like the “radix” setting on RSLogix5 and RSLogix500 if you’re already familiar with those software packages ...



here are examples of two BOOL tags ...







notice that tag “X” has its “style” set for “binary” ... the “2#” notation in the value column just means that the data is being displayed in “binary” notation ... all of those extra (unused) positions are usually quite confusing to a technician who is just looking for a simple indication of the BOOL tag’s “1” or “0” status ...



notice that tag “Y” has its “style” set for “decimal” ... since “decimal” is the default style, there is no special notation shown in the value column - just the simple “1” or “0” status that most technicians are expecting to see when they monitor this BOOL tag’s value ...



finally ... you can easily change a tag’s “style” setting even after the tag has been defined and used ... just click the appropriate cell in the tag’s style column and you’ll get a pull-down list of choices ... note that changing the “style” this way will not change how the controller functions ... it only changes the way that the data is displayed on your screen ...

Thank you for your replies

shaarawi1984 said:

Other option:

using DINT data type.

e.g. Process_Run_Current_State.0

Click to expand...

The dint method is an option. It will conserve processor memory, also, as you get 32 internal digital points for the cost of one tag.

There is a downside, however. You would have to describe each bit individually in the program for your documentation purposes. These descriptions do not get saved to and uploaded from the processor, as the tag names do.

Example: "Main_Motor_Running" as a boolean tag name comes back from the processor as "Main_Motor_Running", when uploaded by someone without your source code. The tag name says it all.

"Main_Motor_Status.0" with the description "Running" attached comes back as "Main_Motor_Status.0"---no description attached---when uploaded.

It's a trade off. If I have all the memory I need, I use boolean data types whenever possible. And if I can't describe the tag function in a 42 character tag name, I need help. I never like to use descriptions in logix 5000 just for this reason--the tagname goes in the processor--the description doesn't.