Hotend PID tuning

  • Hi guys,

    I'm not sure what i'm doing wrong here, i'm trying to PID tune a 12v 30w E3D hotend,

    I'm sending command,

    M303 H1 S280 P0.1

    But getting error,

    Error: Temperature reading fault on heater 1: temperature above limit

    no matter what P setting i use i get the same error.

    Any suggestions? I can't set S any higher because i get,

    Bad parameter in M303 command


  • administrators

    It looks to me that you have a massively over-powered heater. Are you using a 12V heater cartridge on 24V power?

    You can increase the temperature limit if you need to using the M143 command. The default is 262C.

  • You got me worried there, had to double check. It's definitely wired to 12v.

    I'll try M143 and report back.


  • administrators

    You can also reduce the P parameter to below 0.1 if you need to. Or try the 1.18 beta firmware, which doesn't need a P parameter when auto tuning, just a target temperature (which will be overshot somewhat).

  • I went for the new 1.18beta, it did give a warning,

    Warning: Heater 1 appears to be over-powered and a fire risk! If left on at full power, its temperature is predicted to reach 602C.

    Saved with M500.


Log in to reply