| 摘要 |
PURPOSE:To enable manual operation even at PLC-down, by directly inputting the information from the limit switches of devices to be controlled and monitoring it, independently the same as the programmable logic controller (PLC). CONSTITUTION:A PLC9 makes operation with the conditions of a limit switch group 5A which shows the state of devices to be controlled 4 and the state of process, and outputs the operating instruction of the devices 4. With the operation of the devices 4, the state limit switch group 5A and the same state of limit switch group 5B as 5A are operated, and the result is inputted respectively to the PLC9 and a computer 8. The PLC9 makes operation of a series of start and stop logic, and a process end condition 14 outputs a process end signal contact 15A. Further, the computer 8 constitutes the end conditions with the state limit group 5B inputted, and outputs the end signal contact 15A and the end signal contact 15B constituting OR circuits and it is advanced to the next process after exciting the relay 15C. |
