主营产品，备件供应，充足库存

Foxboro（福克斯波罗）：I/A Series系统，FBM全系列（现场输入/输出模块）

顺序控制、梯形逻辑控制、事故追忆处理、数模转换、输入/输出信号处理、

数据通信及处理等。

Westinghouse（西屋）：1C31系列DCS系统、CPU、OVATION系统、WDPF系统、

WEStation系统备件。

Triconex（英维思）:冗余容错控制系统、基于三重模件冗余（TMR）结构的现代化的容错控制器。

EMERSON（艾默生）:模块、卡件、驱动器等各类备件。

With the development of chemical automation technology, the idea of distributed control is more and more popular among the majority of automation engineering technicians, and is gradually applied in the new, expanded and technical reform projects. But the traditional distributed control system is usually produced by professional manufacturers, which has certain specialty; In addition, the traditional distributed control system generally has a large scale of control and high cost; Therefore, it limits the application of the project in the small and medium-sized automatic control system. So how to realize the idea of distributed control in small and medium-sized control system? With this problem, the author summarizes and compares the control system of DCS and PLC based on reading a large number of technical data, and puts forward the idea of using PC + PLC to form DCS in medium and small scale chemical projects, and has been successfully applied in the liquid ammonia storage and transportation section of the technical transformation project of Guizhou Hongfu Industrial Development Co., Ltd. which has annual output of 800000 tons of heavy calcium plant to ammonium phosphate. 1. basic principle of DCS realized by PC and PLC