1. The purpose of the control program acquired by the PLC, achieved MES process control, quality control, historical data retrospective
2. Probably flowchart
3. There are three places associated to achieve the above functions, the first step is to manage the MES, provided those processes specified product, the PC program sweep when the product bar code, checking step, determining whether the step OK, NG, then this step can not be done program instructions sent to the PLC, PLC lock, workers can not operate the equipment for processing, whereas the OK command issued PLC, unlocking the device, for processing, after processing, has PLC completion signal, when the PLC processing program read class data, such as torque, the pressure (and the matching criteria values MES, determine whether the product passed). Locked again after reading the PLC, a closed loop is completed, the next cycle of operation of the scan code.
4. a complete closed-loop, scan code - "Analyzing -" unlock PLC- "Processing -" processing is completed - "Read PLC value -" locked PLC.
The PC interface is probably as follows:
6. a computer for each production line, serial servers used, each step of this production line scan code gun changed all connected to this computer, this computer on a PC program. (PC program PLC communication with all production line scanner)
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