Hotend fault

  • I keep getting hotend fault while trying to print…

    I just want to make sure that I have done everything properly

    Custom CoreXY, Duet 0.8.5 board, V6 E3D hotend with silicone sleeve.


    M305 P1 R4700 T100000 B4725 C7.06e-8

    M305 C7.06e-8

    On the M305, the "e" isn't capital, could this cause an issue, should I go with C0.0000000706?

    I did the M303 H1, I did not use P or S at first it was saying over-powered, I did the M500 & added the M307 H1 A"Gain" C"Constant" D"Dead time" B0 in the config.g.

    Now it gives me the error that it's not increasing fast enough…

    I assume that I did something wrong, so I deleted my M307 command in config.g and the config-override.g

    I had neglected

    Correcting the temperature calibration of Duet 0.6 and 0.85. boards
    The ADC on the Duet 0.6 and 0.8.5 is not calibrated automatically, so you may need to calibrate it in order to get accurate readings, especially at low temperatures.Here's how:

    With the machine cold, see what temperatures the are displayed for the bed and hot end(s), and compare that with room temperature.
    Add H parameters in the M305 commands to get readings close to room temperature. If the readings are too low, use a positive H parameter to bring the readings up to the correct value. If the readings are too high, use a negative H parameter. All heater numbers should need the same value of H parameter - any residual differences you see are probably caused by thermistor tolerances. You should never need to use an H parameter below -100 or above 100, and it is rare to need a value outside the range -30 to 30.
    Very important! Check that if you disconnect the thermistors, the temperature in the web interface reads as error. If instead it reads a very low temperature, reduce the H parameters until it does report error, then reduce them a bit more.


    Other then that, is there any thing that I might have over looked?

    Thanks you

  • The usual cause of heater temperature not increasing fast enough during a print is that the part cooling fan is blowing cold air over the nozzle. Try printing with the part cooling fan off just to check. If that cures it, then you need to look at redesigning things so that the part cooling fan does not blow air over the hot end/nozzle. Depending on your hot end, you may be able to fit a silicone sock which should help.

  • administrators

    What M307 values did you get from tuning the heater?

  • I will post them once I get home from work.

    Could the speed of printing be causing cause the fault?

    I am printing PETG (until I am done with the enclosure and air filter) I set up the speed in the slicer at 20 20 the speed ATM isn't important, I am printing bracket to replace the metal one that I hand made (not has precise) and I noticed that if I print at 50% speed (in the web controller), I usually get faults but when I set it to 100% I run flawlessly…

  • administrators

    You may need to increase the allowed temperature variation for high speed printing. See the wiki for details.

  • Will do thanks you

  • Here is My M307:

    M307 H1 A21.5 C244.3 D5.6 B0

    The speed didn't really help… now I keep getting

    Error: heating fault on heater 1, temperature excursion exceeded 15.0C


    Error: heating fault on heater 1, temperature rising much more slowly than the expected 0.0°C/sec

    I believe that it could be noise… is it normal that the values keep changing even after the fault?

    How do we fix that issue?
    Is there specific wires that can protect from that?

    Is there a way for a fault to cause a pause?

    For PETG printing that could help saving on material, low warping so the pause shouldn't be an issue... a code that we could input at the beginning of each print that would cause a pause until cancelled or until the heater is back at the correct temperature and then continues the print


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