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I need to do some research on Mitsubishi PLC program. I want to download original program (made by someone else, I have no source code) and save on PC (with GX developer) from PLC, play a little with its copy (on PLC) and then upload original program to PLC. Is it safe ? Will PLC work as before manipulating program ? Are there any traps ? Is you can guess I'm starting my adventure with this technology
https://www.youtube.com/watch?v=4VL2sTWmOdw