| 摘要 |
PURPOSE:To prevent malfunctions due to troubles of input media and to improve the reliability, by utilizing a specific idle time of the process control time to diagnose automatically output signals of plural input media at intervals of a constant time. CONSTITUTION:In a process sequence controller, a CPU finds a specific idle time of the process sequence control time to transmit signals Q1 and Q2 for driving switches 12 and 13 for the purpose of taking in signals from plural input media 110-11n having optical electric characteristics for recognition of operation and positions of a process. When switches operate contacts 12a and 13a, respective media transmit detection signals. These signals have waveforms shaped through integral networks consisting of C0R0-CnRn and output buffers 150-15n and are transmitted to the CPU side. The CPU compares these detection signals with signals for normalcy which are prepared preliminarily by a diagnostic program; and if abnormality is detected, the CPU stops immediately the step advance of the sequence control. |
