| 摘要 |
<p>A plant control system fulfils the following functions: 1) preparation and execution of an integrated control program for the diagnosis of interlock conditions, 2) display of a ladder circuit composed of a plurality of factor signals when plant equipment cannot be started, and 3) display of a ladder circuit only composed of a plurality of factor signals and their trigger signals when the plant equipment abnormally stops. The plant control system is provided with program editing means (10) to prepare a control program including the interlock conditions and interlock diagnoses, plant control means (CONT) to execute program objects in the control program, a logic operation device, a display device, and interlock diagnostic means (20) which updates and displays a time of completion or failure of the interlock conditions at a predetermined timing prior to the current timing or the time of the latest failure of the interlock conditions, specifies only originating factor variables of such failure even when a plurality of interlock circuits are formed, and automatically displays the variables in a graphical language.</p> |
