| 摘要 |
PURPOSE:To evaluate accurately and easily the complete state of important parameters in plant operation and supervision by supervising a rate of change of the parameters, its direction and the present value additionally in informing the alarm state of the parameter to a supervisor. CONSTITUTION:A process data inputted by a process input device 12 is subjected to rate of change calculation 13, its output is fed to an alarm area decision device 29, result of decision of alarm area is outputted based on limit values A1, A2 and sectioned into plural area by an A/D converter 30-2 and outputted to an adder 31. On the other hand, the data from the device 12 is inputted also to an alarm decision device 27 to the present value, the result decided based on limit UL, CUL, LL, CLL is converted into plural region signals by an A/D converter 30-1 and outputted to the adder 31. Then the region signal added by the adder 31 is inputted to alarm discriminators 32, 33 and outputted (35,36) as variable alarm in response to the decided alarm state. |
