In the field of electrical engineering, there is no absolute or unique “ultimate path.” The true “path” lies in a profound understanding of the hierarchical relationships and divisions of labor among these three components in industrial control systems, and based on this, constructing an irreplaceable knowledge system. Their relationship is more like a team rather than competitors.
1. Role Positioning: Clarifying Domains, Each with Their Own Responsibilities
We can liken a complete industrial control system to a human nervous system:
1. PLC – The Reliable “Spinal Cord” and “Reflex Center”
· Positioning: A “dedicated computer” designed specifically for industrial environments. It is at the top of the control hierarchy, responsible for directly driving actuators (such as motors and valves), processing sensor signals, and executing logical sequence control.
· Features: High reliability, strong anti-interference capability, simple programming (mainly ladder diagrams), and a mature ecosystem (with a large industry library and protocol support).
· Advantages: In scenarios involving high voltage, high power equipment, harsh environments, and high demands for safety and stability (such as automotive production lines, chemical processes, and elevator control), PLCs are the undisputed kings. Its value lies in “stability” and “specialization.”
2. Embedded Systems – The Intelligent “Cerebral Cortex” and “Complex Decision-Making Center”
· Positioning: A dedicated computer system customized for specific applications, centered around microprocessors/microcontrollers. It is located in the middle or front end of the control hierarchy.
· Features: Extremely high flexibility, powerful functionality, controllable costs, and close integration of hardware and software.
· Advantages: Focused on implementing complex algorithms, fine control, intelligent decision-making, human-machine interaction, and data communication. For example, the main control board of smart homes, drone flight control, robotic vision processing, and the core of high-end CNC systems. Its value lies in “intelligence” and “dynamism.”
3. Microcontrollers – The “Heart” and “Basic Execution Unit” of Embedded Systems
· Positioning: The hardware core of embedded systems. A microchip that integrates CPU, RAM, ROM, and I/O ports.
· Features: Extremely low cost, compact size, and ultra-low power consumption.
· Advantages: It is the cornerstone for implementing embedded products. It is widely present in PLCs (as their controllers), smart instruments, electric toys, keyboards, and mice. It can be said that without understanding microcontrollers, one cannot deeply understand embedded systems, and it is even difficult to grasp the underlying secrets of PLCs.
Relationship Summary: In a complex system, it is often the “embedded system (brain)” that makes intelligent decisions, directing the strong electrical equipment’s actions safely and reliably through the “PLC (spinal cord),” while the numerous small intelligent nodes throughout the system are managed by countless “microcontrollers (nerve endings).”
2. Prioritization and Analysis: How to Choose Your Path?
For students in electrical engineering, the choice should not be “one of three,” but rather “who to focus on and how to integrate them.”
1. If you have a traditional electrical background and seek stable, high-paying jobs in industrial automation:
· Preferred Path: Master PLCs.
· Analysis: This is the path that aligns most closely with the electrical profession and has the broadest employment opportunities. From equipment maintenance to system integration, from automation engineers to project managers, PLC technology is a necessity in manufacturing. Its learning curve is relatively gentle, and the return on investment is very clear. Mastering PLC means you have gained the “voice of authority” in the industrial field.
· Recommendations: Not only should you be proficient in programming, but you should also deeply learn about peripheral technologies such as variable frequency drives, servo drives, touch screens, and industrial networks (like Profinet, EtherCAT). Additionally, you must have a solid foundation in electrical knowledge (relays, contactors, sensors, motors, and drives), which is your core advantage over computer science professionals.
2. If you have a strong interest in electronic technology and programming, and wish to venture into more cutting-edge and intelligent fields:
· Preferred Path: Delve into embedded systems (including microcontrollers).
· Analysis: This is a forward-looking choice. With the rise of the Industrial Internet of Things (IIoT), artificial intelligence, and edge computing, the traditional boundaries of PLCs are being eroded and expanded by embedded and PC-based controls. Mastering embedded systems means you have the ability to design the “brain,” not just use the “spinal cord.” The career ceiling is higher, allowing you to enter golden fields such as consumer electronics, automotive electronics, and the Internet of Things.
· Recommendations: This path presents greater challenges. You need a solid foundation in C programming, digital circuit basics, and a willingness to delve into the fundamentals, studying chip architecture, peripheral drivers, and real-time operating systems (like FreeRTOS). Starting with microcontrollers (like STM32) is a necessary step.
3. Ultimate Strategy: Integrate Knowledge to Become a Master
For those aspiring to become top talents in the electrical field, the true “ultimate path” is:
“PLC as the body, embedded systems as the soul, microcontrollers as the foundation.”
· With PLC as the body: Deeply understand the needs, standards, and safety regulations of the industrial field. This is the foundation for electrical engineers.
· With embedded systems as the soul: Endow systems with intelligence, networking, and flexibility. This is the engine for achieving technological breakthroughs and innovations.
· With microcontrollers as the foundation: Gain insight into the working principles of hardware at the lowest level, allowing you to not only know how things work but also understand why they work, equipping you with the ability to design and solve problems at the chip level.
Conclusion and Priority Recommendations:
1. For short-term employment and stability: Prioritize mastering PLCs, as this is the most direct monetization path for electrical professionals. Understanding microcontroller principles will also help you grasp the limitations and advanced applications of PLCs.
2. For long-term development and breakthroughs: Prioritize deepening your knowledge of embedded systems (starting with microcontrollers), as this is a strategic choice for the future and enhancing core competitiveness. Understanding the application scenarios of PLCs will enable your designed “brain” to better collaborate with the industrial “body.”
3. For the ideal state, becoming an expert: Pursue both paths simultaneously. Use PLC thinking to understand industrial needs, and employ embedded technology to implement innovative solutions. An electrical engineer who understands both industrial processes and can develop embedded hardware and software is the true “ultimate path” that enterprises seek.