Asee peer logo

A New Approach To Teaching Programable Logic Controller Programming

Download Paper |


2007 Annual Conference & Exposition


Honolulu, Hawaii

Publication Date

June 24, 2007

Start Date

June 24, 2007

End Date

June 27, 2007



Conference Session

Unique Developments in Engineering Technology

Tagged Division

Engineering Technology

Page Count


Page Numbers

12.77.1 - 12.77.11



Permanent URL

Download Count


Request a correction

Paper Authors


Donald Harby UCM

visit author page

Donald Harby is an associate professor of Engineering Technology at University of Central Missouri. His research interests include automation, machine tool design and control, and technical education. He has over 15 years of industrial manufacturing and automation experience. He received his BS from Parks College of St. Louis University in 1991, and his MS from the University of Missouri-Columbia in 2002, and expects his PhD from the University of Missouri-Colubmia in 2007.

visit author page


Patricia Polastri UCM

visit author page

PATRICIA POLASTRI is a Ph.D. fellow at Indiana State University, and an instructor at the University of Central Missouri. She has several years experience in the automobile manufacturing industry in Europe. She received her BS from University of Orebro in 1998, and her MS degree from the University of Central Missouri in 2005.

visit author page


Chakapong Chuenprasertsuk UCM

visit author page

Chakapong Chuenprasertsuk is an international graduate student at University of Central Missouri. He is pursuing M.S. Industrial Technology while working as a Graduate Assistant in the School of Technology. He graduated from Kasetsart University, Thailand with B.Eng. Electromechanic Manufacturing Engineering in 2005. His undergraduate thesis was the Design and Implementation of Biomechanical Force Plate. He has two internship experiences at University of Wollongong, Australia and PepsiCo (FritoLay), Thailand.

visit author page

Download Paper |

NOTE: The first page of text has been automatically extracted and included below in lieu of an abstract



The Programmable Logic Controller (PLC) is used widely in industries to control processes and manufacturing systems. There are several analytical approaches for developing PLC programs which are state diagrams, Petri Network and diagrams, truth tables, and Boolean algebra. All of these approaches are useful in developing a sequence of controlling PLC programs in complex systems, but none of these lead to a full automated way of developing a program. In the traditional way of teaching PLC programming such as the state diagram, a diagram is first constructed showing all the possible paths the process can take. Then the Boolean conditions necessary for each path are added. The diagram is then converted to a PLC program and tested. Changes are made to the Boolean conditions and then the new program is tested again. This process of trial and error is continued until a bug free program is developed. This trial and error step does not lead to an automated program development technique. This paper proposes a new approach to controller design and sequence control programming to be used by teachers and industrial trainers. This new method would be a useful tool for teaching beginners a faster way of developing a PLC program. This new approach combines some of the key concepts from various techniques to deliver a novel but effective automated method. This new technique translates in two easy steps truth tables into Ladder Logic Diagram, which is the most common graphical language for PLC programming. An example of a typical hydraulic station was used to demonstrate the analytical method. This example shows that this new analytical and systematic approach can be used to develop the sequence control program of complex systems. This new teaching technique has been applied to engineering technology students. A research study was conducted to verify the usefulness of this method. The study separated engineering technology students in two groups. One group was taught PLC programming in the traditional way, while the other was taught using the new method. Using the same test, the results showed that the group exposed to the new technique spent less time programming, when compared the other group.


In recent years many approaches to developing a systematic or analytical method for PLC programming have been investigated. These approaches include various types of programming, such as state diagrams, Truth Tables, Petri networks and diagrams and Boolean algebra2. All these methods are unquestionably useful in the development of PLC programs, but none has led to a fully automated way of developing a program. The project here presented, combines some of the key concepts from the above mentioned techniques to produce a unique and effective automated method.

The state diagram approach is one of the most used methods2, showing the flow diagram for sequential processes. First a diagram is constructed, showing all possible paths the process can take; and then Boolean conditions are added for each present path. The diagram is then easily converted to a PLC program and tested. Changes are made to the Boolean conditions and then the new program is tested. This process of trial and error continues until a bug free program is

Harby, D., & Polastri, P., & Chuenprasertsuk, C. (2007, June), A New Approach To Teaching Programable Logic Controller Programming Paper presented at 2007 Annual Conference & Exposition, Honolulu, Hawaii. 10.18260/1-2--1949

ASEE holds the copyright on this document. It may be read by the public free of charge. Authors may archive their work on personal websites or in institutional repositories with the following citation: © 2007 American Society for Engineering Education. Other scholars may excerpt or quote from these materials with the same citation. When excerpting or quoting from Conference Proceedings, authors should, in addition to noting the ASEE copyright, list all the original authors and their institutions and name the host city of the conference. - Last updated April 1, 2015