What is a PLC?

So, what is a PLC?

PLC stands for “Programmable Logic Controller”. It is an electronic device used to control machines and industrial processes. PLCs are designed to automate specific tasks, such as controlling machines on production lines, manufacturing systems, industrial processes and more.

In Brazil, the device is called CLP (Controlador Lógico Programável), which is simply the Portuguese acronym for PLC.

A PLC is made up of a processor, memory, input and output interfaces, and a program stored in memory. It performs logical and mathematical operations based on the programmed instructions to control the operation of machines and processes. PLCs are widely used in industrial automation because of their flexibility, reliability and ease of programming.

Automation and control professionals often use specific programming languages to create the programs that PLCs will run. These programs determine how the PLC will respond to the different conditions and events in the industrial process it is controlling.

Main Advantages

• Lower cost: given the large number of relays and the maintenance they require, PLCs become a more viable option.
• Immunity to electromagnetic noise: the PLC has an isolation system that protects against electrical noise.
• Easy to configure: with modular racks, input and output modules can be swapped to meet a specific need.
• Easy to program: the languages used are easy to learn and use, which makes building the control logic simpler. Besides being easy, these languages allow more complex operations than those possible with relays.
• Great flexibility: thanks to the languages used, modifying the process logic becomes much simpler.
• Greater control: as a microprocessor-based device, it lets the user interact with the hardware through software, which makes troubleshooting very practical and easy.
• Online monitoring: several controllers can be connected and communicating with each other, and through this connection we can monitor processes in real time.
• Simple maintenance: the PLC itself often indicates when errors exist

Now that industries are using a new piece of equipment to automate machines and processes, a new professional is needed: the PLC Programmer. Today, industries and factories cannot compete in the market without automating their industrial processes. So, wherever there is automation, there will be a Programmable Logic Controller and the need for a qualified professional.

Main Manufacturers

Ever since the PLC was invented and introduced to the industrial automation market, industries have become increasingly dependent on PLCs, as they saw how many benefits a small, rugged device like the PLC can offer. As a result, many electronic equipment manufacturers recognized the needs of this market and began developing their own programmable logic controllers.

Today, the automation market has many PLC manufacturers, such as:

Siemens, Rockwell, Schneider Electric, ABB, GE FANUC and many other manufacturers. The Brazilian market also has a few PLC manufacturers of its own, such as WEG, based in Santa Catarina, and Altus, based in Rio Grande do Sul.

Online PLC Programmer Course

If you want to learn everything about PLCs from scratch, we recommend FM4's PLC Programmer Course. Click here to learn more about the course. The PLC used in the PLC Programming Course is the Nexto Xpress PLC from Altus. And why this PLC? Besides Altus being one of our partners in developing FM4's courses, the Nexto Xpress PLC uses the same programming software as small, medium and large PLCs. In other words, you learn to program in software that has no limitations based on the size of the PLC. Unlike other courses, which use small PLCs and, as a result, limited programming software with few features, the Nexto Xpress PLC lets you program using a wide range of programming features regardless of the PLC's size.

Conclusion

Programmable Logic Controllers (PLCs) are fundamental to modern industrial automation, offering a robust, flexible and efficient solution for controlling processes and machines. Over the years, the evolution of PLCs has enabled industries in many sectors to significantly increase their productivity and quality, reducing operating costs and minimizing human error.