Main Components of a PLC
Their are mainly 6 major part of a PLC that are :
- Processor
- Memory(RAM/ ROM)
- Input device
- Output device
- Power supply
- Programming device
Description of each part of a PLC :
- CPU : CPU is the brain of a PLC, responsible for executing the control program stored in memory. It performs tasks such as data processing, decision-making and communication with other devices.
- Memory(RAM/ROM) : PLCs have main type of memory one is ram and another is rom. RAM is used for storing data and variables temporarily during the execution of the program. ROM is used to store the operating system of a PLC and the user program. The program typically consists of two ladder logic, function block diagrams or other programming languages.
- Input Device : This is responsible for interacting with the machine and the instructor which can be external sensors, switches etc. This part helps to take input and send to to the CPU to response accordingly.
- Output Device : Output device is responsible for interacting with the end point external device like motor, valve or indicator. It converts control signal from the PLC that these devices can interpret.
- Power Supply : PLC requires a stable power supply to run its program and match the voltage levels that needed for a PLC components.
- Programming Device : As PLC is mainly a programmable device, so we need a device where we can write code and execute it, just like a monitor and keyboard.
What is a Programmable Logic Controllers (PLC)
PLC stands for Programmable Logic Controller which was invented in automobile manufacturing to provide a flexible, rugged, and easily programmable controller to automate a system in the year of 1964 by Dick Morely. That’s why he is called as father of PLC. The first PLC was Medicon 084. These PLCs were large, expensive, and not easy to maintain and program. That’s why in the next generation it was upgraded to medium and small size PLCs. It is a hardware device with microprocessor-based control system. PLC is a general-purpose computer modified specially to perform control tasks. It is used for industrial automation to automate a specific process, machine function, or even entire production. PLCs are developed for electronic replacement for hard-wired relay logic circuit systems for machine control. They are designed for industrial use to control many automated processes in industries.
In this Article, We will go Through what is a Programmable Logic Controller and how a programmable logic controller works, We will go through Different types of PLC, Then we will proceed with PLC programming Examples and see industrial PLC programming examples, At last, we will conclude our Article with its Applications, Advantages, Disadvantages and Some FAQs on PLC.
Table of Content
- What is a Programmable Logic Controller (PLC)?
- Use of PLC
- Components of PLC
- Structure Of PLC with diagram
- Working of PLC controller
- Types of PLC
- Applications of PLC