Yokogawa Electric Corporation

Makio Ishikawa

Hideyuki Sakamoto

Toshiaki Shirai

Chuji Akiyama

Hitoshi Yasui

Hideo Matsukawa

Yasuhiko Shioe

A distributed control system comprising a control station and a remote input/output device interconnected by a bus, wherein the system is provided with a continuation transmission service which first transmits an urgent output only and then performs cyclic scan transmission; an initialization start transmission service which first performs cyclic scan transmission for input only; an interruption duration measuring feature which measures the period of transmission interruption; and a control feature which activates the continuation transmission service when the result of the measurement is shorter than a predetermined period of time, and which activates the initialization start transmission service when the result of the measurement is longer than the predetermined period of time. Thus, for example, after a power supply failure, the system can rapidly recover and shift to normal process controlling operation without the delays normally experienced by prior control systems.

Growing community of inventors

Tokyo, Japan

Makio Ishikawa