| 摘要 |
PURPOSE:To make it possible to exactly execute an abnormal diagnosis peculiar to the triple system and to perform a process control with high reliability, by changing the electric power source of the pulse type final control element. CONSTITUTION:As a result of a self-diagnosis of the A system computer, when an output of the self-normal diagnosis is gone, an output of the AND gate 41 becomes ''0'', the relay 15-1 is returned and at the same time the gate 50 is opened. In case the self-diagnosis of the B system is normal, the relay 16-1 is operated by an output of the B system is normal, the relay 16-1 is operated by an output of the gate 50, and the B system computer is selected. In this regard, in case the self-diagnosis of the B system computer is not normal either, the gate 51 is opened, and in case the self-diagnosis of the C system computer is normal, the C system computer is selected. Also, as for selection of each computer, the result of mutual diagnosis is added, and as a result of mutual diagnosis of the A system computer by the B and C system computers, in case both of them are abnormal, even if the self-diagnosis of the A system computer is normal, it is changed to the B and C system computers. Also, in case one of them is abnormal, the A system computor is selected. |
