Programmable_Logic_Controllers

Programmable Logic Controllers ABSTRACT The purpose of this report is to elaborate the achievements in Programmble Logic Controllers as well as their implementation in the current engineering world. CONTENTS 1- Introduction 2- Design • Advantages Of PLC design • Operation Implementation • Programing 3- Conclusion 4- References INTRODUCTION A PLC (i.e. Programmable Logic Controller) is a device that was invented to replace the necessary sequential relay circuits for machine control. The PLC works by looking at its inputs and depending upon their state, turning on/off its outputs. The user enters a program, usually via software, that gives the desired results. PLCs are used in many "real world" applications. If there is industry present, chances are good that there is a plc present. If you are involved in machining, packaging, material handling, automated assembly or countless other industries you are probably already using them. If you are not, you are wasting money and time. Almost any application that needs some type of electrical control has a need for a plc. For example, let's assume that when a switch turns on we want to turn a solenoid on for 5 seconds and then turn it off regardless of how long the switch is on for. We can do this with a simple external timer. But what if the process included 10 switches and plc, step, first, plcs, input, time, programming, program, output, typically, turn, data, based, standard, relays, physically, one, need, inputs, during, counters, count, connected, world, type, logic, ladder, external, exist, control, upon, through, system, switches, store