DCS distributed control systems (Distributed Control System), short for domestic General called the distributed control system. It is a process control level and process monitoring levels of communication networks–a link to the multiple computer systems, integrated computer (Computer), communications (Communication), display (CRT) and a control (Control) 4 c technology, the basic idea is decentralized, centralized operation, classified management, flexible configuration and easy configuration. DCS have the following characteristics:
(1) high reliability because control functions on the computer of the DCS system is implemented on the system using fault-tolerant design, so a computer failures will not lead to the loss of other functions of the system. In addition, because the tasks assumed by each computer in the system is single, required functions using with a specific structure and dedicated computer software, so that every computer in the system‘s reliability is also improved.
(2) open DCS open, standardized, modular and series design, each computer in the system using local area network communication, information transmission, when you need to change or extend system functionality, new computers can be easily connected to the communication network or remove it from the network, worked almost without affecting other computer systems.
(3) flexibility through configuration software based on different process applications for hardware and software configuration, namely the identification of measurement and control signals and connections, control algorithm library, select the applicable control rules and from the graphics library called basic graphics needs of a variety of monitoring and alarm screen, conveniently with the necessary control systems.
(4) easy to maintain small or micro-features a single dedicated computer, with simple, easy maintenance features, when a local or a computer failure, can be made without affecting the entire system running online Exchange, rapid troubleshooting.
(5) coordination of data transferred over a communication network between the various workstations, the entire system for information sharing, coordination, and to complete the overall function and optimization of control systems.
(6) the rich control functional control algorithm, set the continuous control, sequential control and batch control in one, can realize cascade, feedforward, decoupling, adaptive and predictive control and other advanced controls, and can easily add a required special control algorithms. The composition of the DCS is very flexible, and can be managed by a dedicated computer station, operators, engineers, recording stations, control stations and data acquisition station and other components, or by the common servers, industrial control computer and programmable logic controller. At the bottom of the process control level usually consists of scattered field control station, data acquisition station for data acquisition and control, production monitoring levels and sent through the network to the computer. Production control-level data from process control level of operation and management, such as optimization, statistical reports, fault diagnosis and alarm. With the development of computer technology, DCS can follow need computer equipment with higher performance through centralized management of network connection to enable more advanced features, such as scheduling, warehouse management, energy management, and so on.