| 摘要 |
<p>A programmable controller (PC) controlling the operation of a machine is described that executes a program written in a sequential function chart (SFC) language. The PC can generate a reverse operation sequence chart from an ordinary operation SFC program sequence chart. This allows the PC to control the machine in the reverse direction. Thus, if a machine experiences a failure, the reverse operation sequence chart is used and reverse operations are performed to allow the cause of the failure to be removed. The ordinary operation can resume without having to restart the sequence from the beginning.</p> |
