Maya saved the original logic to an SD card, then wrote a new password onto a piece of duct tape and stuck it inside the panel door.
She was a freelance industrial automation specialist, and this was the job from hell. The "Harvest King" grain elevator in rural Nebraska had been silent for a week. A lightning strike had wiped the memory of the main PLC, and the backup was, in the owner’s words, “eaten by a raccoon.” s7-200 smart plc password unlock
The only remaining copy of the ladder logic was trapped inside this locked CPU. Maya saved the original logic to an SD