【正文】 iguration. (8) Use of new technologies such as optical fiber munication DCS in its development process and draw upon a variety of advanced technology. Optical fiber munications, highdensity largecapacity disk surface mount technology, voice synthesis and recognition, multimedia, and other new technologies, as well as lowpower CMOS RISC processor and other devices and has been in some of the new DCS has been fully applied. Optical fiber munications technology in the application of。s software platform and the emergence of applications, the application provides a unified software development tool. Application Platform features from the PCindustry data exchange within the factory to the coordination of multiple systems, the standard data interface allows puter control equipment and exchange of data and information works, for integrated information management and control system provides great convenience. Along with the standard graphical operating system continuously improve and develop, process control and industrial automation package greatly enriched, the industrial PC applications will increasingly strong. Three, the characteristics and Application of DCS DCS since its birth, after decades of continuous improvement, development and modernization has been very mature. Compared with the early, the scale of their — 8 — systems, control functions, and other areas have been tremendous developments in changes in the reliability, flexibility, adaptability, scalability, costeffective integrated technical indicators have seen increased and improved. Has been widely used in petrochemical, pharmaceutical, energy, chemicals, paper, oil refining, metallurgy and food and beverage, and other industries, and has made very significant economic and social benefits. According to statistics, production facilities from analog instruments to DCS control the economic benefits can be achieved by the overall efficiency of 60%. DCS average payback period for 12, after the introduction of advanced control strategies can reduce the payback period of to 1 year. DCS is today into various kinds of advanced control technology and equipment, and to the prehensive integrated information management and automated process control systems, that is, CIMS direction. 1. Development process From 1975, the DCS roughly experienced the 1975 ~ 1980, the first generation, from 1980 to 1985 the second generation, and after 1985 the third generation of three stages of development. Many manufacturers take DCS phased development strategy, adopted in the early systems continue to develop and improve, then launched with a variety of new features of the new system, the new system patible with the original equipment homogeneous. Early DCS storage capacity small, relatively simple function. System modules include process control, process interface modules, CRT operator station, control puter and data Highway, Part 5. Its characteristics are using microprocessors to achieve decentralized control, CRT operator station and the process control unit separation operation carried out on display and remote control configuration. Honeywell pany TDC2020 is the first generation of the representation of DCS products. DCS mainly by secondgeneration local area works, multifunction controllers, the puters, enhanced operator station, multifunction operator station, the connector between the work, system management module, and other ponents. Its characteristics are achieved more thoroughly decentralized control, decrease in the number of wiring, and antiperformance enhancement, improved level of standardization of hardware, high universality, function more prehensive. Not only — 9 — strengthened control, and strengthening the systemwide information management, the introduction of local area works and fiber optic munications technology. During this period the representation of the pany products include Honeywell TDC3000 and Westinghouse WDPF systems. DCS new generation is the most important feature of the process control, monitoring, management, scheduling organically integrate, through the use of open systems and standards such as MAP munication works, such as Ether and Fieldbus solve different manufacturers equipment interconnection between issues. During the system is the development of a number of new features, using a 32 or 64bit microprocessor, and a powerful workstations and enhanced the sequence control, volume control, the system can acmodate industrial PC and PLC。s size and function in accordance with the needs of users of its own portfolio. (4) easy to learn programming. Most of the PLC programming relay control circuit similar to the ladder diagram form, the user, do not have puter expertise, it is easy to general engineering and technical personnel understand and master. (5) Installation is simple and easy maintenance. PLC does not require specialized equipment room in a variety of industrial environments can be directly run. Various — 4 — modules are run and fault indication devices, userfriendly understanding of the operation and find fault. The modular structure, so any failure of a module, users can replace the module, allowing the system to rapidly resume operation. Second, the characteristics and Application of industrial PC 1. Industrial PC industrial control applications Industrial PC hardware and software support of a broad, diverse varieties can take full advantage of excellent graphical user interface capabilities, the industrial users an enormously attractive. Early PC but not suitable for industrial process control automation applications, such as increasing modified by strengthening the protection of the case, such as cooling damping taken measures to meet the industrial environment is the application of some of the requirements of th