Duet Ethernet not connecting anymore



  • Hi,

    I think I shorted my IR Sensor to one of my Z-motors via my heatbed clamp.
    Now it does not connect to my ethernet anymore.
    When I power it on the following LEDs are on:

    LED E1 Heat (red)
    LED E0 Heat (red blinking)
    LED VIN (blue)
    LED +5V (red)
    LED +3.3V (green very dim)

    The Hotend and Heatbed are getting hot.

    Is there a way to rescue the board?


  • administrators

    @shackman said in Duet Ethernet not connecting anymore:

    I think I shorted my IR Sensor to one of my Z-motors via my heatbed clamp.

    Do you mean that the IR sensor shorted to one of the Z motor connections, or to the body of the Z motor?



  • I believe it shorted to the leadscrew. So to the body of the motor.



  • or maybe to Heatbed -


  • administrators

    @shackman said in Duet Ethernet not connecting anymore:

    or maybe to Heatbed -

    That would certainly explain it. A short to Heatbed- would feed VIN into the IR sensor any time that the bed heater is not running at full power. So VIN would get fed into the +3.3V rail. Ouch!



  • so it's dead?

    And is the IR-Probe dead too?


  • administrators

    Sadly, they are probably both dead. The processor on the IR sensor is rated at 7V absolute maximum. You could try applying 3.3V or 5V between Vcc and Gnd, to see if it will still initialise and flash the LED.

    The processor on the Duet is rated at much less than that. The fact that the 3.3V LED is dim suggests that something on the 3.3V rail is drawing too much current. You will probably find that U2 and at least one other component on the Duet are getting hot.

    It's probably not much consolation, but you are not the first. In the early days of the Ormerod 1 printer there were a few instances of kit assemblers fitting the aluminium bed plate upside down. This caused one of the bed heater terminals to touch it. Then the proximity sensor (another type of IR sensor) would sometimes short against the clips holding the glass top plate in place... and that would feed 12V into the 3.3V rail.



  • Yes, U2 and the main processor are getting very hot a few seconds after applying power via the usb port.

    OK thats sad, but thank you for your fast help


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