New Data Transmission and Acquisition Method for a Process Control System
Shinichi Yamada, Hideji Fujikawa · 1987
Recent process control systems show a tendency to grow increasingly in scale and become more complicated with the progress of instrumentation system. To achieve economical data transmission an: acquisition of an enormous amount of information, Hybrid Local Area Network has been developed. This LAN can be connected with a computer or a control device and has compaibility with sensors and actuators in terminal station. Normally, the data transmission and acquisition is performed by the roll-call poling method. In emergency, random access signals are transmitted by the contention method. This method is a highly flexible multiplex transmission which will be met the microcomputer based distributed process control system.