An Unconventional Guide to PLCs

Often engineering newbies (like myself) hear a lot of terms that are spoken of in the same paragraph: SCADA, Ladder Logic, OMRON, human machine interface…

An industrial computer, the PLC.

These terms are some of the things heard when people talk about industrial automation, mechatronics or process control. Each is equally deep and wide in scope, but a common point they have is PLCProgrammable Logic Controller.

PLCs are the computers that run big machinery. This is the simple definition.

But for someone who has to learn what they are, what they’re used for, how to program them, or even SEEING one, textbooks and lecturers are generally vague and disappointing. They are very important, and yet, only specialists in companies involved in big scale engineering, who have gone on (very) expensive courses live and work around them each day.

Rumour has it that a PLC course will be organized in Western Johannesburg, maybe this year, possibly next year…

To learn more about PLCs, check out the tutorials at