Contact and Coil | Nearly In Control

RSLogix 5000 Tutorial

This is a free introductory tutorial on how to create an automation program for a ControlLogix or CompactLogix processor using the RSLogix 5000 programming environment from Rockwell Automation.

If you would like to follow along with the tutorial, Rockwell Automation has graciously offered a 90 day demo of RSLogix 5000 as a free download. It’s fully functional, except it won’t communicate with a real PLC.

The tutorial explains how to write the automation program including the ladder logic and sequential function chart for a domestic washing machine. I chose a Cat investigates washing machinewashing machine because it’s quite simple, and it’s something that everyone is familiar with. I should, however, note that you would never put an industrial controller into a domestic washing machine, and you probably wouldn’t ever use a servo motor for the agitator, but I wanted to demonstrate a little motion control as well. I have heard that newer washing machines actually have VFD control, but I admit that servo control is overkill.

I also don’t have any real knowledge of how a washing machine works internally, other than using my imagination, so please don’t use this as a reference if you happen to be designing, programming, or building a real washing machine!

  1. Creating a new project
  2. Customizing the editor and colors
  3. Adding I/O cards
  4. Creating the axis for the servo motor
  5. Program structure: High level program layout
  6. Program structure: How to layout routines
  7. Mapping your inputs
  8. Mapping your outputs
  9. Create fault logic
  10. Create the low level machine control routines
  11. Create the automatic sequence
  12. Tie the automatic sequence logic to the outputs


12 comments

  • The Five Rung Logic Block - Contact and Coil · June 17, 2010 at 11:10 pm

    [...] RSLogix 5000 Tutorial [...]

  • Darrell Hazelwood · December 8, 2011 at 9:10 am

    Step 12 needs to be hyperlinked. Your tutorial is great.

  • Mesta's Automation blog » Blog Archive » PLC programming resources: PLC-DEV website · January 30, 2012 at 1:12 pm

    [...] blog to learn Allen Bradley programming (and ladder in general) is Nearly In Control with his RsLogix 5000 tutorial, PLC DEV contains a mass of documentation about Allen Bradley and their products. Some useful post [...]

  • waltj · February 12, 2012 at 5:10 pm

    Please advise when step 12 is completed! Loved thetutorial…thanks!

  • Yogesh · February 18, 2012 at 1:10 pm

    Why we not uses the microcontrollers & others processing units i think they are easy to program.

    Why we use special processors please tell me the processor requirments of a plc system ??

    your tutorial is very very good & helpful.

  • Alexandre Noguchi · November 29, 2012 at 7:54 pm

    Great tutorial, helped me a lot, thanks!

  • Wayne · January 28, 2013 at 5:29 am

    Brilliant tutorial, looking forward to step 12

  • Chris Pitts · February 5, 2013 at 5:05 pm

    @Yogesh,

    There are a number of reasons to use PLC’s over microcontrollers.

    First, it’s important to understand that PLC’s and uC’s are actually very similar in terms of their core processing capabilities. Lots of PLC’s run Freescale or other processors that you will see in common microcontrollers. The hardware differences center around the different applications they revolve around.

    First, microcontrollers are designed to automate processes in systems that are produced on a very large scale. Typically, when you design a uC solution, you design it to perform a single task, and you design it to be mass produced without changes from unit to unit. When you need to automate a process such as engine management in an automobile, for example, uC’s are the obvious choice because they are inexpensive, powerful, and effective. Building a million cars with PLC’s in them would be insane compared to uC’s, even if both systems had equal processing power.

    By contrast, PLC systems are designed to implement processes that are custom for each application. They are designed such that the engineer can easily modify the number of inputs and outputs available, and the larger PLC solutions are designed to scale to huge numbers of I/O points that a single uC could never accomodate.

    The other difference is that uC’s don’t typically have the hardware integrated for doing I/O at voltage levels other than what the processor operates at. PLC’s are designed to do AC and DC discrete logic, as well as 4-20mA analog, among other things. uC’s need support hardware before they can do that. Essentially, a PLC IS a microcontroller; that support hardware to take in those inputs seamlessly is the primary thing that makes them different. You could run a factory using an ATMEL uC, but you would need all the support hardware to plug in the huge amount of I/O.

    I’m fairly new to PLC’s. I’ve only recently started an internship with an industrial automation company. But having used uC’s pretty extensively, I hope that answers your questions as to the differences between the two systems.

  • Author comment by Scott Whitlock · February 28, 2013 at 2:34 pm

    @Chris Pitts – well said. Both technologies have their place.

  • It’s not about the machine, it’s about the man. « Industrial Training · April 24, 2014 at 10:02 pm

    […] Scott by day does PLC, .NET, VB6, and SQL Server programming. In the evenings Scott and his wife run a question and answer site for parents called moms4mom.com, then on the weekends he writes and maintains an open source framework called SoapBox Core for developing extensible .NET applications. Somehow, Scott still finds time to produce an excellent blog, which is how I found him. A must read for all our followers, see http://www.contactandcoil.com/rslogix-5000-tutorial/.  […]

  • Raindawg · June 8, 2014 at 8:58 am

    I’m interested in step 12…. Anyone?

  • InqThinker · August 22, 2014 at 4:48 am

    I’m also interested in step 12. Also, perhaps step 11 can be expanded on as well? An example of a completed FBD would be very useful.

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