PLC

 PLC PROGRAMMING Machine control design is a unique area of engineering that requires the knowledge of certain specific and unique diagramming techniques called ladder diagramming. Although there are similarities between control diagrams and electronic diagrams, many of the component symbols and layout formats are different. This chapter provides a study of the fundamentals of developing, drawing and understanding ladder diagrams. We will begin with a description of some of the fundamental components used in ladder diagrams. The basic symbols will then be used in a study of Boolean logic as applied to relay diagrams. More complicated circuits will then be discussed. Control Transformers For safety reasons, machine controls are low voltage components. Because the switches, lights and other components must be touched by operators and maintenance personnel, it is contrary to electrical code in the United States to apply a voltage higher than  120VAC to the terminals of any operat...

PLC PROGRAMMING LANGUAGES Programmable Logic Controllers (PLCs) are the major components in industrial automation and control systems. A PLC program consists of a set of instructions either in textual or graphical form, which represents the logic to be implemented for specific industrial Realtime  applications. A dedicated PLC programming software comes from a PLC hardware of specific manufacturer that allows entry and development of user application code, which can be finally download to the PLC hardware.  Before going to the program of the PLC, let us know the basics of the PLC programming tutorial and its basic concepts. The controlling nature of PLC is ranging from simple- push button switching to a single motor to several complex control structures. Once this program gets downloaded to the PLC and if the PLC is placed in Run mode, then the PLC continuously works according to the program. This software also ensures Human Machine Interface (HMI) as a graphical representatio...

  PLC FULL FORM (Programmable logic controller) A Programmable Logic Controller, or PLC, is a ruggedized computer used for industrial automation. These controllers can automate a specific process, machine function, or even an entire production line.  A PLC program is usually written on a computer and then is downloaded to the controller Most PLC programming software offers programming in Ladder Logic, or “C”. Ladder Logic is the traditional programming language. It mimics circuit diagrams with “rungs” of logic read left to right. Each rung represents a specific action controlled by the PLC, starting with an input or series of inputs (contacts) that result in an output (coil). Because of its visual nature, Ladder Logic can be easier to implement than many other programming languages.  “C” programming is a more recent innovation.  Some PLC manufacturers supply control programming software. In a traditional industrial control system, all control devices are wired direct...