PLC System

A programmable logic controller (PLC) is a small, modular solid state computer with customized instructions for performing a particular task. PLCs, which are used in industrial control systems (ICS) for a wide variety of industries, have largely replaced mechanical relays, drum sequencers and cam timers.PLC are divided into three types based on output namely Relay output, Transistor output, and Triac Output PLC. The relay output type is best suited for both AC and DC output devices. Transistor output type PLC uses switching operations and used inside microprocessors.PLCs are made up of input points or modules, output points or modules, and a CPU (central processing unit). Inputs accept a wide range of analog and digital signals from different sensors/ field devices and work to convert them into logic signals that are CPU compatible.