| 摘要 |
PURPOSE:To study early a fundamental factor that produced the operation variance by obtaining a stability coefficient from the measured value of each process variable and displaying these coefficients in the form of a pattern. CONSTITUTION:When either one of process variables reaches an alarm level, a CPU22 produces an alarm. At the same time, the CPU22 calculates the stability coefficients before 1, 2 and 3 minutes from the alarm produced point for each process variable and displays these coefficients in the order of larger absolute value and in the form of a pattern on a CRT display device 25. Further, a fault state of each instrument is displayed on a CRT display device 25. Then the CPU22 calculates the stability coefficient of each process variable every time the countermeasure enable time, e.g., 1min elapses, and absolute value of the stability coefficient is displayed in the display device 25 as pattern in order from large value at each point of time. |
