IASC Sector Skill Council

PLC Programmer and Troubleshooter

In the realm of industrial automation, Programmable Logic Controllers (PLCs) stand as the cornerstone of efficient and reliable operation. These specialized computers are the brains behind the automation processes in manufacturing plants, power generation facilities, and various industrial settings. The role of a PLC programmer and troubleshooter is pivotal in ensuring these systems function seamlessly, optimizing production, and swiftly resolving any technical glitches that may arise. Let’s delve into the intricate world of PLC programming and troubleshooting to understand its significance and the skills required to excel in this field.

Understanding the Role:

PLC programmers and troubleshooters are the architects behind the automation systems that drive modern industries. Their responsibilities encompass a wide array of tasks, from designing and implementing control algorithms to diagnosing and rectifying malfunctions in PLC-based systems. Their work directly impacts the efficiency, safety, and reliability of industrial processes.

Skills and Expertise:

Becoming proficient in PLC programming and troubleshooting requires a blend of technical skills, problem-solving abilities, and a deep understanding of industrial processes. Here are some essential skills for aspiring PLC programmers and troubleshooters:

  1. Programming Proficiency: Mastery of programming languages specific to PLCs, such as ladder logic, Function Block Diagram (FBD), Structured Text (ST), and Sequential Function Charts (SFC), is fundamental. A thorough understanding of these languages enables programmers to create complex control algorithms tailored to the specific requirements of each industrial application.
  2. Electrical and Electronic Knowledge: A solid foundation in electrical engineering principles and electronics is indispensable for PLC programmers. Understanding circuits, sensors, actuators, and other components allows them to interface PLCs with various devices and troubleshoot electrical issues effectively.
  3. Problem-Solving Skills: PLC programmers and troubleshooters must possess exceptional problem-solving skills to identify, analyze, and resolve issues in automation systems promptly. This involves a systematic approach to troubleshooting, logical reasoning, and the ability to think critically under pressure.
  4. Familiarity with PLC Hardware: In-depth knowledge of different PLC models, their features, and hardware configurations is essential. This includes understanding input/output modules, communication protocols, memory structures, and peripheral devices commonly used in industrial automation.
  5. Software Proficiency: Proficiency in PLC programming software, such as Siemens TIA Portal, Allen-Bradley RSLogix, or Schneider Electric Unity Pro, is vital. These software tools provide the interface for developing, testing, and debugging PLC programs, making them indispensable for PLC programmers and troubleshooters.
  6. Safety Standards and Regulations: Adherence to safety standards and regulations is paramount in industrial automation. PLC programmers must be well-versed in relevant safety codes, protocols, and best practices to ensure the safety of personnel and equipment in industrial environments.
  7. Continuous Learning: Given the rapid evolution of technology in the field of industrial automation, PLC programmers and troubleshooters must be committed to continuous learning and skill development. Staying updated with the latest advancements, emerging technologies, and industry trends is essential to remain competitive in the field.

Roles and Responsibilities:

The roles and responsibilities of PLC programmers and troubleshooters may vary depending on the specific requirements of their employers or projects. However, some common tasks include:

  1. PLC Programming: Designing, developing, and testing PLC programs to control industrial processes efficiently and accurately.
  2. System Integration: Integrating PLCs with other automation components, such as Human-Machine Interfaces (HMIs), Supervisory Control and Data Acquisition (SCADA) systems, and Industrial Internet of Things (IIoT) devices, to create seamless automation solutions.
  3. Troubleshooting and Diagnostics: Identifying and resolving faults, errors, and malfunctions in PLC-based systems through systematic troubleshooting techniques.
  4. Maintenance and Upgrades: Performing routine maintenance tasks, software updates, and hardware upgrades to ensure the optimal performance and reliability of PLCs.
  5. Documentation: Documenting PLC programs, system configurations, and troubleshooting procedures for future reference and knowledge sharing.

Challenges Faced:

Despite the advancements in PLC technology, PLC programmers and troubleshooters encounter various challenges in their day-to-day work. Some common challenges include:

  1. Complexity of Systems: Modern industrial automation systems are becoming increasingly complex, with interconnected PLCs controlling numerous processes simultaneously. Understanding the interactions between different components and subsystems can be challenging.
  2. Legacy Systems: Many industrial facilities still rely on legacy PLC systems, which may lack compatibility with modern software tools and programming languages. Retrofitting or upgrading these systems without disrupting operations requires careful planning and execution.
  3. Time Constraints: In industrial settings, downtime can be extremely costly. PLC programmers and troubleshooters often face pressure to diagnose and resolve issues quickly to minimize production losses.
  4. Interdisciplinary Collaboration: Effective troubleshooting often requires collaboration with professionals from various disciplines, including electrical engineering, mechanical engineering, and process engineering. Communicating technical issues and solutions across different departments can be challenging.
  5. Continuous Learning: Keeping pace with advancements in PLC technology, software tools, and industry standards requires a commitment to lifelong learning. PLC programmers must invest time and effort in staying updated with the latest developments in the field.


In conclusion, PLC programmers and troubleshooters play a crucial role in the realm of industrial automation, ensuring the efficient operation of PLC-based systems and minimizing downtime through effective troubleshooting and maintenance. Mastering the art of PLC programming and troubleshooting requires a combination of technical skills, problem-solving abilities, and a deep understanding of industrial processes. By staying updated with the latest advancements in technology and continuously honing their skills, PLC programmers can navigate the complexities of modern automation systems with confidence and proficiency, contributing to the success of industrial operations worldwide.