Industrial control is a wonderfully complex interdisciplinary topic. It covers topics ranging from three-phase motor controllers all the way to the latest cybersecurity for our critical infrastructure. This can be challenging for a learner interested in the field.
This engineering brief provides recommendations to help get you started.
Note: Use this page to your advantage by adding your automation questions to the comments. We may integrate them into the body of this post or split them into new threads.
Troubleshooting: While not addressed in this note, be sure to read the industrial troubleshooting guide.
This article is part of the DigiKey Field Guide for Industrial Automation
Location: Teach It → Industry Context
Difficulty: 
Student — difficulty levels explained
Author: Aaron Dahlen | MSEE | Senior Applications Engineer, DigiKey
Last update: 06 Mar 2026
Figure 1: Image of a PLC trainer featuring Schneider components.
Why is it so hard to learn industrial controls?
There was a time when I didn’t understand electronics or automation. While I had some education, I struggled to understand the applications. For instance, I could program a microcontroller but had yet to program a control loop.
What I’m trying to say is that we are not born with the electronics knack. Instead, it is something that is developed over time with deliberate practice or real-world experience.
Tech Tip: Thermal control systems can oscillate. Early in my career I was working on the cooling system for a radio transmitter. It featured a standalone Proportional-Integral-Derivative (PID) controller to control a proportioning valve’s motor. This system would automatically divert cooling water to external radiators or circulate the water in a local loop to retain the heat. The system was broken as the water was constantly being circulated outside causing the interior system to freeze.
Troubleshooting revealed that the proportioning valve’s motor was burned out. After installing the new motor, I noticed that it was cycling between full open and full closed every minute. The new motor would not last long with this constant hunting.
The solution was to do something we technicians were told to never do. I adjusted the gain setting on wall-mounted PID controller. With the gain reduced, the motor stopped hunting, and the system freezing was eliminated.
Getting started in automation
Mapping the terrain is an important part of the learning process. This is especially true of industrial controls. A useful, albeit old-school, learning method is to obtain a catalog. For example:
- Siemens
- Schneider
- Phoenix Contact
- Omron
- Others? Leave a comment in the space below.
As you thumb through the catalogs, pay attention to how things are grouped together. This activity reveals the map.
Pushbuttons
To get started, consider something as simple as pushbuttons. Using the map, we can go to Pushbutton Valley. There we find a dizzying array of options spanning over a hundred pages in the catalog.
With regards to DigiKey, you will find that many devices are prebuilt. An example is the Schneider XB5AA31 as shown in Figure 2. You will also find that the parts are individually available. Suppose you discovered a broken contact block, instead of ordering the entire switch you could purchase the block independently with considerable cost savings.
Figure 2: Representative Schneider pushbuttons.
Figure 3: Representative Siemens lighted pushbutton.
Thermal control
On another day, we could follow the map to Thermal Town. Leading to standalone thermal controllers such as the Omron E5CC-RX3A5M-000 thermal controller. This is the modern equivalent to the PID controller mentioned in the Tech Tip. While you are there you can explore related devices, accessories, and thermal probes. Taken together this trip will improve your ability to categorize industrial control systems.
Figure 4: Representative standalone Omron PID thermal controller.
PLC and related devices
On another day, we travel to the PLC plaza. Perhaps you will be diverted to the PLC Power Supply Trail and discover that 24 VDC uninterruptible power supplies are available for your PLC. An example is the Phoenix Contact 1133819 as shown in Figure 5.
Figure 5: Representative Phoenix Contact PLC backup power supply battery.
Recommended industrial control learning resources
As you continue your journey, you will need mentors and wizards to guide your path. They will help you understand the terrain and the relationship between components.
Allow me to share links to material that I have found helpful, especially when I was teaching:
- Tim Wilborne
- Alicia Gilpin Muñoz (Ali G)
- Paul Lynn
- PLC Professor
- My old material constructed prior to joining the DigiKey team
- Others? Leave a comment in the space below.
Parting thoughts
You’re on an honorable quest to join the masters of industrial automation. Welcome to a field where your perseverance and curiosity light the way. I wish you every success as you discover the meaning of machine control to cybersecurity and everything in between.
We look forward to answering your question and helping you find solutions.
Best wishes,
APDahlen
Continue Exploring Industrial Control Systems
If this discussion was helpful, you may also want to explore:
DigiKey Navigation
- Full Catalog: Industrial Control & Automation
About This Author
Aaron Dahlen, LCDR USCG (Ret.), is a Senior Applications Engineer at DigiKey in Thief River Falls. His background in electronics and industrial automation was shaped by a 27-year military career as both technician and engineer, followed by over a decade of teaching.
Dahlen holds an MSEE from Minnesota State University, Mankato. He has taught in an ABET-accredited electrical engineering program, served as coordinator of an electronic engineering technology program, and instructed military technicians in component-level repair.
Today, he has returned to his home in northern Minnesota, completing a decades-long journey that began with a search for capacitors. Read his story here.