Duet 3 Mainboard 6HC bed not heating



  • I have a table from Ender. It is 24V table with built-in temperature sensor.
    I connected table to out0 pins on the mainboard 6hc.
    The config file has such strings for bed heater:

    ; Heaters
    M308 S0 P"temp0" Y"thermistor" T100000 B4138 ; configure sensor 0 as thermistor on pin temp0
    M950 H0 C"out0" T0 ; create bed heater output on out0 and map it to sensor 0
    M307 H0 B0 S1.00 ; disable bang-bang mode for the bed heater and set PWM limit
    M140 H0 ; map heated bed to heater 0
    M143 H0 S120 ; set temperature limit for heater 0 to 120C
    M308 S1 P"temp1" Y"thermistor" T100000 B4138 ; configure sensor 1 as thermistor on pin temp1
    M950 H1 C"out1" T1 ; create nozzle heater output on out1 and map it to sensor 1
    M307 H1 B0 S1.00 ; disable bang-bang mode for heater and set PWM limit

    Thermistor works. It shows room temperature at "Bed temperature field".
    When I turn on bed heating, it does not work. The led near out0 is also does not turn on.
    The voltage does not change (stays 0.0V).
    SO if I wait long enough, I reasonably get a fatal error "heating error"

    One more thing is that if I try to turn another heater (out1), nothing changes. It also does not change voltage on out1.
    Maybe(?!) I have to something like "activate" heating somewhere else?

    Yes, I have M501 string at the end of the config file.
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  • Moderator

    Out0 is powered by the Out0 Power In terminals directly beside it. This allows for connecting a separate PSU of a different voltage or higher wattage than that used for VIN on the rest of the board.

    You can either connect it directly back to the PSU or bridge it across to the VIN terminals.

    alt text


  • Moderator

    Out0 is powered by the Out0 Power In terminals directly beside it. This allows for connecting a separate PSU of a different voltage or higher wattage than that used for VIN on the rest of the board.

    You can either connect it directly back to the PSU or bridge it across to the VIN terminals.

    alt text



  • Thank you.


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