2020. 2. 22. 02:26ㆍ카테고리 없음
PLC: Industrial Applications of Programmable Logic ControllerIn the most basic terms, a programmable logic controller is a computer with a microprocessor but has no keyboard, mouse or monitor. It is essentially built to withstand very harsh industrial environments.It is a distinctive form of computer device designed for use in industrial control systems.
Programmable Logic Controller Plc
It has a robust construction and unique functional features such as sequential control, ease of programming, timers and counters, easy-to-use hardware and reliable controlling capabilities.It is designed to be enormously robust, so it could withstand harsh industrial environments such as extreme temperatures, vigorous vibrations, humidity and electrical noise.The logic controllers are often tasked to control and monitor a very large number of sensors and actuators. They are therefore different from other regular computer systems in their extensive I/O (input/output) arrangements.In addition to being used as a special-purpose digital computer, the PLC can be used in other control-system areas and industries.
This explains why PLCs are often referred to as industrial PCs.The PLC is also commonly used in civil applications such as in washing machines and for controlling traffic signals and elevators. They are used in many industries to monitor and control production processes and building systems.Once programmed, the PLC will perform a sequence of events triggered by stimuli referred to as inputs.
It receives these stimuli through delayed actions such as counted occurrences or time delays.These special computer devices are different from regular computers such as PCs or smartphones in that:. 1.
A PLC performs only a single set or sequence of tasks, with greater reliability and performance, except when it is under real-time constraints. This is in contrast to regular PCs and smartphones that are designed to execute any number of roles simultaneously within the Windows framework.
Programmable Logic Controllers Pdf
2. The PLC has a number of features that you don’t find in normal computers, such as protection from the open area conditions like heat, dust and cold. 3. It is low cost compared with other microcontroller systems. When you’re using a PLC in various applications, you only need to change the software component for each application. With other microcontroller systems however, you would have to change the hardware components too with different applications.This microprocessor- based controller includes a programmable memory that stores instructions and implements functions that include sequencing, timing, logic, arithmetic, and counting.How programmable logic controllers workEach PLC system has three modules namely: CPU module, power supply module and one or more input/output (I/O) module.
Programmable Logic Controllers
CPU ModuleThis module is comprised of a central processor and its memory component. This processor performs all the needed data computations and processing by receiving inputs and producing corresponding outputs. Power supply modulePLC’s computer circuitry runs on a 5V DC output and this is supplied by the power supply module.