Title:
PLANT SUPERVISORY AND CONTROLLING SYSTEM
Document Type and Number:
Japanese Patent JPS6394301
Kind Code:
A
Abstract:
PURPOSE:To easily switch a current system/spare system in a plant supervisory and controlling system by separating a duplex master station device into the current system and the spare system, connecting to separate networks to control. CONSTITUTION:When the system rises, a central processing unit 1 sets the current system (for instance, an I system highway 4) to a current section information area 8 and uses current system master station TC/TM device groups 6 to collect data and command a control. A packet is delivered from the spare system master station TC/TM device groups 7 of other system II main highway 5 for every constant cycle to monitor the state of the device. At this time, when an abnormality is generated in one of the master station devices of the current system, the central processing unit i checks the state of the master station device groups 7 of the spare system and rewrites the current section information 8 if the device groups 7 are normal, switches the system to a II system main highway 5 and uses the device groups 7 to collect the data.
Inventors:
OGATA TAKANORI
Application Number:
JP24062386A
Publication Date:
April 25, 1988
Filing Date:
October 08, 1986
Export Citation:
Assignee:
NEC CORP
International Classes:
G05B9/03; (IPC1-7): G05B9/03
Attorney, Agent or Firm:
Uchihara Shin