| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a CPU duplexed control system that can soundly operate systems without executing an unnecessary system changeover while all stations PIO are abnormal. <P>SOLUTION: The CPU duplexed control system including each PIO 11 and 12 connected to a first system 1 and a second system 2 by a field network 10 includes a first PIO master 5 of a control system and a second PIO master 6 of a standby system, which are connected to each PIO 11 and 12 via the field network 10. The first system 1 performs a mutual live check of the first PIO master 5 and the second PIO mater 6. When a first CPU 3 detects all abnormalities of the PIO 11 and 12 from the first PIO master 5, the first CPU 3 determines whether or not the second PIO master 6 is normal from the live check. When the second PIO master 6 is normal, the system changeover is not executed. When the second PIO master 6 is not normal, the system changeover is executed. <P>COPYRIGHT: (C)2013,JPO&INPIT |
