DCS System Architecture

DCS System Architecture: DCS System Architecture – The building block concept of electronic control design, with distributed proc­ess controlled boxes linked together by a communication network, was first introduced by Honeywell in 1975. Today, the monitor and control boxes connected to the Data Hiway as shown in Fig. 21.77 are an integral part of the […]

DCS System

DCS System: A DCS System is preferred over a central computer system for the following reasons. Central Computer System (CCS) exposes the plant to the risk that the system might fail. This can be minimized by having one or more back up schemes. A back up computer Analog controller Manual loading stations Various combinations of the […]

Distributed Control System

Distributed Control System: Distributed Control System – Since the beginning of process control in late 1970s, it has made great progress in every control activity. Similar to the other electronic equipment, its size is decreasing and its power is increasing. The conventional instrumentation is now outdated. The speedy development in the field of electronics has […]

PLC Hardware Components

PLC Hardware Components: PLC Hardware Components – The input and output interface modules consists of an I/0 rack and individual I/O modules. Input interface modules, accept signals from the machine or process devices (120V ac) and convert them into signals (5V dc) that can be used by the controllers. Output interface modules convert controller signals […]

Basis of PLC Programming

Basis of PLC Programming: 1.Processor Memory Organisation:The term processor memory organization refers to how certain areas of memory in a given Basis of PLC Programming are used. Different PLC manufacturers organize their memories in different ways. Even though they do not use the same memory make up and terminology, the principles involved are the same. […]