PT 100 reads 2000C



  • Hi All

    I've recently purchased the Duet WiFi with the 2 pin PT 100 sensor and daughter-board.

    After configuring my software through the reprap configurator. I've been able to home the axis and test the heated bed. However the pt100 just reads a constant 2000C.

    I've found this post which seams to be the same issue.
    https://forum.duet3d.com/topic/1292/pt-100-temperature-constantly-at-2000-degrees-after-failure/19

    Following what was posted there I can see that my PT 100 does indeed have a 100+ ohm resistance when disconnected or connected.

    M305 P1 X0 followed by M305 P1 X200, works fine so it can communicate with the chip on the daughter board,

    Same when run for 201, I've also verified the error reporting is working by trying a channel I don't have such as 202 or 203. and sure enough I get the error.

    Any idea's on next steps?



  • I've managed to resolve the issue, Incase anyone else comes across this thread in future.

    When selecting "Sensor Channel" in the reprap firmware, I mistakenly put PT100 on E0 input, Changing to MAX31856 on CS1 resolved my issue.


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