It works, but the documentation is non-existent

By: David Hunter on 25 October 2020

This sensor works... once you know how to wire it. It ships with no documentation at all so I had to open it up and figure out which pins correspond to what. Orient the sensor assembly with the arrow pointing away from you, so that you are looking directly at the 3-pin connector, and so that the two gaps in the 3-pin connector (for the two lugs in the cable's connector) are up. The signal output pin is the left pin. Ground is the middle pin. 3V input is the right pin. Also, this sensor comes without any cables either. You'll need to provide your own. I describe this in more detail in a Reddit post: https://www.reddit.com/r/3Dprinting/comments/jdwa6c/whenever_i_plug_this_filament_sensor_into_my_rpi/

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