MicroLogix 1000 vs. 1100 Part One: Program files

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While the MicroLogix 1000 is the least expensive RSLogix based PLC from Rockwell Automation (starting around $150,) it’s also the most limited.

That in mind, in today’s article we’ll compare the MicroLogix 1000’s “Program Files” with the MicroLogix 1100’s, as they are the only two MicroLogix PLCs supported by the free version of RSLogix Micro we discussed last week.

When you create a new MicroLogix 1000 program, you’ll notice that unlike other MicroLogix, the SLC-500 and PLC-5, you have several Ladder Program Files created for you automatically, instead of just the typical default ladder program 2:

MicroLogix Program Files-S2-E41-TAB-01

This is because the MicroLogix 1000 has very limited memory, and to accommodate this Rockwell expands the program files to the maximum supported in this processor.

What this means is, you not only can’t create additional Ladder files, but LAD 3, 4, 5, and 16 have already been assigned functions. This leaves Lad 6-15 for user subroutines:

MicroLogix Program Files-S2-E41-TAB-02The MicroLogix 1100 on the other hand is more like the rest of the MicroLogix line (and the SLC-500 and PLC-5.)

When you create a new program, you’ll see just the standard LAD 2 program file:

 MicroLogix Program Files-S2-E41-TAB-03

And like the SLC-500 and PLC-5, you can right click on “Program Files” to create new Ladder routines:

MicroLogix Program Files-S2-E41-TAB-04

Note: While you can create Ladder Programs 3 through 255, you likely wouldn’t have enough memory in the 1100 to actually file all 254 program files with programs of any substantial size:

MicroLogix Program Files-S2-E41-TAB-05

And that’s it for our look at the differences in Program files between the MicroLogix 1000 and 1100.

If you’d like to learn how to use and program both the MicroLogix 1000 and 1100, I suggest checking out my affordable MicroLogix video training course at PLC-Basics.com:


And to see a video of the comparison, check out the below episode of The Automation Minute:


Shawn Tierney
Automation Consultant
Insights In Automation

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