| 摘要 |
<p>PURPOSE:To improve reliability by setting a synchronizing signal pattern with prescribed steps that changes only once in one operating cycle of a controlled facility in a normal pattern storage part set as reference, and comparing it with an actual pattern. CONSTITUTION:The title device is equipped with an I/O state input part 15 to input an input/output signal, an operation change detecting part 16, and the normal pattern storage part 17, and forms a sequence monitoring device of playback system. The storage part 17 makes a facility 1 perform a normal operation and store an operating pattern at that time as a reference pattern at every step in which the pattern transits. Also, at a comparison part 18 which compares the actual operating pattern detected by the detecting part 16 with the above reference storage pattern, the presence/absence of discrepancy is monitored, and a diagnosed result is supplied to a diagnostic result output part 22 and a comparison execution control part 19. In such a way, I/O that changes only once in one cycle and in which no order is changed is set, and a limit step specified by the above result is set as a synchronized step, then, monitoring is restarted.</p> |
