Error: M140

[A Former User]

hello friends i need help please every time i start heating my bed i get this error (M140 P0 S90
Error: M140: Can't turn heater 0 on while in fault state)

[dc42]

@sgk have you run heater tuning on the bed heater?

[A Former User]

@dc42 yes yes of course more than once

[dc42]

@sgk in that case, the first time after you run M140 after power on, there should be a message telling you that the heater has faulted, and why.

You can reset a heater fault in DWC.

[droftarts]

@sgk something caused the heater to fault, so you need to find that first. Clear the heater fault, then turn on the heater. If it faults again, it should say why, and probably that it is heating too slowly. Post your firmware version and hardware with M115, the heater config and what the heater setup is.

Ian

[A Former User]

@droftarts m115
FIRMWARE_NAME: RepRapFirmware for Duet 3 MB6HC FIRMWARE_VERSION: 3.4.4 ELECTRONICS: Duet 3 MB6HC v1.01 FIRMWARE_DATE: 2022-10-20 16:19:01

[A Former User]

M308 S0 P"temp0" Y"thermistor" A"Bed" T100000 B3950 ; configure sensor 0 as thermistor on pin temp0
M950 H0 Q10 C"out0" T0 ; create bed heater output on out0 and map it to sensor 0 (if NOT using SSR - delete Q10)
M307 H0 R0.678 K0.477:0.000 D4.24 E1.35 S1.00 B0 ; 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 100C

[A Former User]

[droftarts]

@sgk see https://docs.duet3d.com/en/User_manual/Connecting_hardware/Heaters_tuning
This page has information on tuning, storing, and manually adjusting heater parameters.

At what point do you get the message? Soon after you turn the heater on, or as it nears the target temperature? I can see the bed got to 74 degrees with a target of 90, so I assume the latter. Can the bed actually achieve 90 degrees? Did you run auto tune with a 90 degree target temperature?

Auto tune can sometimes produce incorrect parameters; we’re looking into why. If the heater continually faults, you can manually adjust the M307 settings.

As it says on the page linked above, I suggest:

If during initial heating the temperature undershoots the target:
RRF 3.3 and later: increase the R parameter by 5% or 10%

Ian

[A Former User]

@droftarts I succeeded I put the hotend at 220 d and after I made the pid of the bed and now it works without error thank you guys for your help

[A Former User]

[droftarts]

@sgk I doubt setting the hot end temperature made any difference. Retuning the bed probably did, though.

Ian

[A Former User]

@droftarts maybe when I did my foot the first time as I didn't turn on my hotend it didn't do my bed pid well