Can I wire a 3-wire proximity limit switch into a blackbox controller? If I can, is there a wiring diagram?
Yes you can. No diagram at this point, but show us the sensors you want to use, most have a sticker on them with pinout to color code mapping.
I don't have the sensors yet but I can get a diagram. This is a description of the sensor: LJ12A3-4-Z/BX New Inductive Proximity Sensor Detection Switch NPN DC 6-36V Can I wire two sensors in parallel to the same connector to create limit sensors on both ends of an axis?
Consider SN-04 NPNs instead, easier to mount than the ones you want to use You cannot use dual switches if you go Inductive, without external circuitry. But you don't need to. Use Soft Limits gnea/grbl - works a treat
Black = SIG Brown = V+ Blue = GND Set Limits-V to 24v: docs:blackbox:jumper-limitswitchvoltage [OpenBuilds Documentation]
NO or NC doesn't matter too much, can invert the inputs, as long as NPN, I think most people run NC. Cheers