What Programming Language Do PLCs Actually Use? A Practical Guide for College Students in USAChoosing the right PLC programming language can shape a college student’s path in automation, engineering, or industrial technology. PLCs (Programmable Logic Controllers) power factories, energy systems, and smart buildings from coast to coast. Skilled programmers keep American industry running. For college students in the USA, learning these languages means better job opportunities and the freedom to solve real industrial problems from the first day at work.

Key PLC Programming Languages College Students in USA Should Learn

Photo by Leonid Altman

PLC programming languages look nothing like everyday computer languages, but they are built for reliability, simplicity, and clarity. Learning the right languages in college pays off quickly.

Ladder Diagram (LD): The Foundation for Beginners

Ladder Diagram (LD), also known as Ladder Logic, sits at the heart of nearly every entry-level PLC course in the US. Most colleges and industry programs start with LD for good reason: it models the familiar relay logic circuits found in real electrical controls.

Why is Ladder Logic so useful for college students in USA?

• Visual format: The language uses symbols and lines, resembling electrical relay schematics, so it’s easy to read and debug.
• Industry standard: Factories nationwide rely heavily on ladder logic. Knowing LD means you’re job-ready right after school.
• Intuitive for beginners: Students can visualize signal flow, connect rungs, and quickly see results in real-time labs.

For more detail on why Ladder Logic remains the top choice, check out this guide to popular PLC programming languages.

Structured Text (ST) and Advanced Control

As systems grow more complex, college students in USA often add Structured Text (ST) to their toolkit. This high-level language mimics the syntax of popular programming languages such as C or Pascal and is often used for computational tasks, state machines, and data manipulation.

Why do advanced students and automation engineers use ST?

• Text-based: Great for those with coding experience, ST uses loops, variables, and control structures, making it powerful for logic-heavy applications.
• Flexible: It handles math, data processing, and recipes better than visual languages.
• Growing demand: Many new automation projects require ST, especially in sectors like process control and energy.

Structured Text helps you bridge the gap between traditional PLC work and more advanced programming challenges, preparing you for a broader range of roles. For an overview of where Structured Text fits in, see this discussion on top PLC programming languages.

Other Essential Languages: FBD, SFC, and Legacy IL

Besides Ladder Logic and Structured Text, college students in USA should have some familiarity with other languages outlined in the IEC 61131-3 standard.

• Function Block Diagram (FBD): Combines blocks that represent logic or functions, making it a favorite for process control and operations that need modular logic.
• Sequential Function Chart (SFC): Organizes programs into steps and transitions, helping visualize and control complex sequential processes found in manufacturing.
• Instruction List (IL): Once common for fast, simple logic but now fading in popularity as modern PLCs and industry trends shift toward visual or text-based languages.
• High-level integrations: Languages like Python are gaining ground in advanced systems, letting students integrate PLCs with HMI/SCADA or IoT solutions. While not a beginner topic, it’s helpful to know for futureproofing your skills.

Reddit discussions among real automation professionals, such as this debate about learning programming languages for PLCs, shed light on practical advice for students.

How U.S. College Students Learn PLC Programming

Colleges across the US design their PLC programs to build practical skills from the ground up, combining theory and hands-on practice.

Hands-On Learning with Simulation and Labs

Experience matters most. Most college courses blend classroom teaching with lab sessions and software simulation. Students write code, connect real PLCs, and troubleshoot on the spot.

• Simulators: Software lets students practice from anywhere without damaging real equipment.
• Physical labs: Wiring up motors or conveyor belts gives students a sense of real-world challenges and safety controls.
• Group projects: Teams often take on mini-projects, mimicking plant automation or assembly line controls.

Colleges such as Penn State Berks offer PLC certificate programs built on this approach, with strong emphasis on hands-on learning.

Curriculum Pathways: From Basics to Advanced Topics

Typical college PLC curricula move in a clear sequence:

1. Introduction: Basics of PLC hardware, wiring, and power.
2. Ladder Logic: Learning fundamental control patterns like switches, relays, and timers.
3. Advanced control: Using Structured Text, Function Block Diagrams, and networking PLCs.
4. Safety and troubleshooting: Diagnosing faults, understanding emergency stop systems.
5. Industry projects: Integrating PLCs with sensors, actuators, and plant networks.

Programs such as the PLC Technician I Certificate are designed to help beginners build strong foundational skills before progressing to advanced concepts.

Connecting PLC Skills to Industry Careers

Learning to program PLCs puts students on a direct path to employment. Automation, manufacturing, and plant operations need skilled technicians and engineers.

• Career fields: Roles include automation technician, controls engineer, plant maintenance, system integration, and process improvement.
• Earning potential: According to the Bureau of Labor Statistics, technicians and engineers in controls and automation often command solid starting salaries and strong job security.
• Job outlook: With American manufacturing modernizing and infrastructure being upgraded, the demand for PLC technicians keeps rising.

Employers seek students who can hit the ground running, making hands-on PLC knowledge a strong asset.

Conclusion

For college students in USA, mastering PLC programming opens doors to rewarding jobs in automation and industry. Learning Ladder Diagram (LD) gives a strong foundation, while picking up Structured Text and Function Block Diagram ensures flexibility and relevance in advanced settings. Classes that blend classroom instruction with labs and simulation help students build real skills that matter.

Those who learn to program PLCs graduate with tools to solve real-world challenges and the confidence to adapt to changing technology—which is exactly what employers need in today’s workplace. Start with the basics, keep practicing, and you’ll build a career that keeps American industry moving.

Frequently Asked Questions (FAQ)

1. What is a PLC?

A PLC, or Programmable Logic Controller, is an industrial computer used to control machines and processes in factories, energy systems, and smart buildings.

2. Which programming language should I learn first for PLCs?

Start with Ladder Diagram (LD), also called Ladder Logic. It’s the most common beginner language and widely used in American industry.

3. Are PLC programming languages similar to regular coding languages like Python or Java?

Most PLC languages, like Ladder Logic, are very different. Structured Text (ST) is closer to common languages such as C or Pascal, but others are visual or symbol-based.

4. Do employers expect students to know more than one PLC language?

Yes. Knowing Ladder Logic is a must, but many jobs also want skills in Structured Text, Function Block Diagram (FBD), and basic understanding of Sequential Function Chart (SFC).

5. How do colleges teach PLC programming?

Colleges use a mix of classroom lessons and hands-on labs. Students learn with real PLC equipment, simulators, and group projects.

6. Is it possible to practice PLC programming without physical equipment?

Yes. Many programs use simulation software so students can write and test PLC code on a computer.

7. What careers can I pursue if I learn PLC programming?

Careers include automation technician, controls engineer, plant maintenance, and system integration specialist.

8. What is Structured Text, and when is it used?

Structured Text (ST) is a text-based language for advanced logic, math, and data processing. It’s used in complex automation tasks and process control.

9. Are PLC programming skills in demand in the USA?

Yes. Skilled PLC programmers are needed in manufacturing, infrastructure, and industrial modernization projects across the country.

10. Do I need a degree to get a job working with PLCs?

A college degree or certificate in automation, industrial technology, or a related field helps. Hands-on skills and certifications are important to employers.