What are PLC systems?

PLC stands for Programmable Logic Controller. This system, as its name suggests, is a system that performs control measures. For example, in industrial processes such as assembly lines and robotic equipment, it controls these processes. On the other hand, it is logical and works with the programming language that is given to it. In this way, the process error does not happen in the systems. In simpler terms, PLC is a software controller that receives binary numbers and processes them according to the program given to it, and sends the output to the receivers through command. So the logic defined for it is easily changeable. For the first time, PLC was used in the automobile industry and with its practical features, it could be used as a relay and timer in this industry.

PLC features are such that it is resistant to harsh industrial environments, cold, heat, dust and moisture. This part is a microprocessor that operates with the help of a program given to it by programmers through the connection of the computer to the PLC. Finally, the PLC must produce the output in a limited time. PLCs are produced from dozens of 0's and 1's compacted with a processor to modular PLC's that have thousands of 0's and 1's and can be used to mount on a rack or connect to a network or other PLCs. Among the features of PLCs, he mentioned the number of analog and digital inputs and outputs, the number of timers, the number of counters, the number of auxiliary relays, memory size and execution speed. The industrial ports present in the PLC make it suitable for communication with other devices. As a result, information exchange will be done faster and PLC will be able to control more accurately. The programming language used in this system is a logic type, the most common of which is ladder logic. There are other languages ​​used for PLCs that can be more useful than ladder logic depending on the application of the PLC, including: Instruction List Function Block Diagram Structured Text Sequential Function Charts

PLCs are divided into different categories based on types, memory and number of inputs and outputs as well as scope of operations. If we want to categorize them based on the number of inputs and outputs, we are faced with two types of PLCs, compact and modular. PLCs can be programmed either modularly or individually. Compact PLC is made of several modules. In fact, the number of input/output capabilities is determined by the manufacturer and has a fixed value. In this type of PLC, you cannot increase the modules. But in modular PLCs, it is possible to increase or decrease the number of modules; As a result, it is up to you to set the number of input/output capabilities of this part. In this type of PLC, you can see the power supply module, processor module, and input and output modules connected in a row. In terms of memory size, they can be divided into large PLCs, medium PLCs, and small PLCs: Small PLCs are a compact and compact piece that is placed next to the control equipment. This small piece can easily replace hardware relay, timer or counter logic. For this type of PLCs, the expansion of the input and output modules is limited. They use relay or logic language to program on it. Medium PLCs are often used in industries that have the ability to connect many modules. Thus, several I/O points with I/O cards connect the modules in this PLC. Large PLCs are also mainly used in situations where complex operations need to be controlled. Large PLCs have more advanced performance than medium PLCs in terms of memory, programming language, number of inputs and outputs, and communication modules. For this reason, it is often used to control information in large dimensions and industrial plants.

A PLC that is used in large industries and various parts is different from a PLC that has local control over smaller parts. In industrial PLCs, information is transferred to the central room through data transmission, and then, using various monitoring methods, this information is digitized and displayed on the monitor screen.

Applications of plc are different in different industries. From the oil and gas industry, in power plants, steel industry, automobile industry, chemical and energy industries, paper and glass industry, and even cement, we see various applications of this part. PLC in the aviation and travel industries also leads to better performance of elevators and escalators as a controller of security devices.

PLC takes very little time to scan and with one computer it can communicate with all the factory systems. PLC systems have high computing power. Learning to use these systems is also easy. These systems have various control applications that have made it possible to use them for different industries. Its programming is simple and the cost of the projects done with this system is more economical than the old control systems. The high monitoring control that this system has increases accuracy and you can change the program you wrote for it whenever you want. If this system has a problem, you can fix the problem easily and faster than traditional systems such as relays. Fast counters shorten project execution time and increase project reliability while maintaining quality and accuracy.