NPN Proximity sensor endstop



  • Hello,

    I am trying to connect a NPN, normally open proximity sensor to my Duet 2 Wifi. The operating voltage is 5 to 60 V.

    5 V and GND are attached to the always on fan pins and the black wire of the sensor to the "Z STOP" pin.

    The sensor is not working and the Z endstop led on the board is on.

    How to wire this kind of sensor? I read the Wiki about Connecting a Z probe, but I am trying to use the sensor as endstop.


  • Moderator

    How do you have your endstops configured?
    What firmware version and Duet board are you using?



  • In config.g:

    M574 X1 Y1 S1
    M574 Z1 S0

    Board: Duet WiFi 1.02 or later
    Firmware: RepRapFirmware for Duet 2 WiFi/Ethernet 2.05.1 (2020-02-09b1)



  • I noticed today that when the sensor is attached the endstop led gives just a bit of light.

    When I connect a photomicrosensor everything works well.

    Does anyone have an idea?


  • Moderator

    Checking...


Log in to reply