Honestly, in the electrical industry, if you're just looking to coast along, this job will be enough to feed you. But if you aspire to a high-paying job and reach the pinnacle of your career, your current skills are far from sufficient.
Why choose to study PLC? There are so many other things to learn.
If you want to live a decent life in the electrical industry and earn a good salary, then becoming an electrical engineer is your first choice. PLC content is usually tested in the intermediate electrician exam, and the application of PLC by senior technicians is even more extensive.
Of course, if you choose to switch careers, then there's no question about it. Learning PLC is an essential step for electricians to transition into electrical engineers. Once you become an electrical engineer, the environment, the people you interact with, and your salary will be vastly different from before.
So how exactly do you learn PLC? Next, I will analyze this in two scenarios:
1. People with zero electrical engineering knowledge
It's not impossible to learn PLC without an electrical engineering background, but only if your physics, math, and computer skills are decent. Otherwise, starting with basic electrical engineering is the most time-saving and labor-saving shortcut.
Talk is cheap, so let's analyze it. To learn PLC, besides understanding the CPU, modules, and system of the PLC itself (those with computer basics will learn faster), you also need to know how to install and wire a PLC, as well as the PLC's computer programming language and instructions. Installation and wiring belong to physical knowledge, while programming languages and instructions are inseparable from logic, mathematics, and computer science.
Therefore, you need to start with the basics of electrical engineering, learning about circuits, resistors, capacitors, electromagnetism, and so on. As everyone knows, the ultimate and greatest use of a PLC is to control equipment, such as elevators, motors, and other high-voltage equipment. Speaking of high-voltage electricity, there is also low-voltage electricity. You should know even more about the power of electricity! This is why we emphasize the basics of electrical engineering. Let's take an example.
Some people who see this GIF might ask: Is this fake? Did he get an electric shock?
(Due to image size limitations, you can find similar GIFs online.)
First of all, this is definitely not fake. Judging from the three construction workers who fell to the ground, they were all stiff and fell straight backward. Under normal circumstances, without safety measures, the chance of injuring the back of the head is very high if a person falls straight backward. So even if it's acting, there's no need to be so desperate.
In academic terms: Electric current refers to the directional movement of electric charge. In simpler terms: electric current is mobile; it can conduct electricity through a conductor, causing an electric shock and creating a circuit. The road sign in the picture has come into contact with 10 kilovolts of high voltage. If the current travels through the conductor and reaches the human body, and a circuit forms within the body, passing through the heart, the chances of survival are slim. Without this basic electrical knowledge, it's not just a workplace hazard, but a significant risk to life.
Therefore, the correct approach is to first learn electrical engineering fundamentals, basic electrical and electronic technology, and electrical diagram reading. Electrical diagram reading will help you recognize electrical symbols such as text and images, and understand the representation methods of components and connecting wires. This will enable you to understand the circuit layout of a room, even a building, or a piece of equipment, accumulating experience for your future projects.
Furthermore, understanding some safe electricity usage techniques will provide an extra layer of protection for your life! Upon seeing this, some people might think, "Learning all this would take forever, it's too much trouble!" Construction workers know that it takes about three months to lay the foundation for a thirty-story building. How much more so when you're learning a skill to support yourself? Everyone can live for decades. Exchanging a few months for decades of returns is a calculation that everyone can clearly make in their minds.
II. People with basic electrical engineering knowledge
First of all, congratulations! Having basic electrical knowledge is half the battle won in learning PLC. Many people ask, when learning PLC, should I choose Siemens or Mitsubishi? Which one is better?
In fact, regarding this question, the only answer is to choose according to your needs.
First, based on your work needs, if the factory requires Siemens or Mitsubishi PLCs, then there's not much to say; just learn the corresponding brand. After all, everyone learns to work better and earn more money, so handling work is the priority. Secondly, you can learn other brands.
If the above conditions are not met, the following suggestions are for selecting a PLC:
1. Choose according to your needs
When learning PLC, Mitsubishi is relatively easy to get started with because it is a Japanese (Asian brand). The programming is intuitive and easy to understand, and the logic is simple, making it easier to learn. However, it has many instructions, so it is recommended to learn Mitsubishi's FX series first.
From a learning perspective and career prospects standpoint, Siemens is a better choice. Siemens is the industry leader in industrial automation, boasts advanced software, and offers a range of closely interconnected products. Learning the Step engineering configuration software on the TIA Portal platform will enable you to operate Siemens S7-1500, S7-1200, S7-300, and S7-400 controllers, as well as the SIMATIC WinAC automation system on PCs. If you want to learn Siemens, it's recommended to start with the S7-200. Although the S7-200 PLC is discontinued, it's relatively simple and, being a Siemens product, there shouldn't be significant differences. Starting with the easier parts and progressing gradually is the best approach.
2. Select according to the characteristics of PLC
Process control and communication control are areas where Siemens excels. Their analog modules are inexpensive, have simple programming, and are convenient for communication. Mitsubishi's analog modules, on the other hand, are slightly more expensive and have more complex programming, resulting in weaker functionality in this area.
Discrete control and motion control are Mitsubishi's strengths. Mitsubishi has a rich set of instructions, including dedicated positioning instructions, making it relatively easy to control servos and steppers. It can also achieve some complex motion control. Siemens, on the other hand, is not as good as Mitsubishi in this regard. Not only does it lack dedicated instructions, but its programs for servo or stepper positioning control are also complex and its control accuracy is not high.
For example, for motion control of robotic arms, a Mitsubishi PLC can be chosen. If servo or stepper motors are required for positioning control, a Mitsubishi PLC is also a good choice.
However, when dealing with devices that require processing analog quantities, such as central air conditioning, sewage treatment, and temperature control, Siemens PLCs are more suitable. In addition, Siemens PLCs are also suitable for field applications that require communication to acquire large amounts of instrument data.
Seeing this, many people ask: Why not mention domestic PLCs? There are domestic PLCs from Delta, Yung-Hung, Hollysys, etc., but most of them are just copies of foreign brands like Siemens and Mitsubishi. This has nothing to do with patriotism; it's just that from a learning perspective, learning the most advanced technologies is a wiser and more beneficial choice for most learners.
