| 摘要 |
PURPOSE:To eliminate a wrong diagnosis of an abnormality, and to raise the reliability by providing a plant abnormal event holding circuit for holding an abnormality detecting input from a plant. CONSTITUTION:An abnormal temperature, etc. of a device 2 of a plant 1 are detected by detectors 3, 7, and they are outputted to a computer 8 through a converter 5. This computer 8 is provided with a plant diagnostic logic 9, a display device, a limit check 10, models 27, 31 which have simulated the device 2, etc., and monitors the plant 1. In this case, an abnormal event holding circuit 36 is provided. In this state, an output which has held a logical signal is outputted to an output from the limit check 10, transmitted exactly to the plant diagnostic logic 9, and the plant can be monitored without causing a wrong diagnosis. Also, when avoiding the subsequent abnormality, it is released by inputting a holding release input 37. |
