After 19 hours of printing: Printing paused:heater fault

FBG

I start my first print, everything is absolutely perfect, is incredible the quality of the prints now….
But, after 19 hours the display show this:

The machine is paused, how i can continue without lose the print part?
What i can check? What happen? What heater is broken? I can see some log?

Duet Wifi Version 1.21 RC5

FBG

In Gcode Console i found 4 messages likes this:

What mean?

dc42

You can clear the heater fault using M562 (see https://duet3d.dozuki.com/Wiki/Gcode?revisionid=HEAD#Section_M562_Reset_temperature_fault)) then press Resume. But see the wiki page on spurious heater faults after your print finishes.

That message suggests a corrupted gcode file.

FBG

Corrupted gcode file? I do with simplify3d like always before.
Can i see something in this?

But you check than show: Error: temperature reading fault on heater 1.
I use Thermocouple K, is possible than do a problem and if show 2000ºC happen this fault or not?

FBG

I do M562 but the error happen again!, is continuously

dc42

If it's happening continuously and it was working before, then something has changed e.g.:

Thermocouple has become disconnected from the daughter board
Thermocouple is shorting to the heater block
Thermocouple broken (gone open circuit)

FBG

Finally i restart the machine….
and now happen this:
I Preheat and the temperature go up 4-5 seconds but show this....
Error: Heating fault on heater 1, temperature rising much more slowly than the expected 1.7°C/sec

dc42

Have run M303 tuning on that heater/thermocouple/hot end combination since you last changed anything?

FBG

Not. I do the first time and the config is saved in config-override and i don't touch anymore

i am doing in this moment a new M303, by the way i add in Config M570 H1 P60 T15.

A question, is possible restart for the point where the machine was paused?

I have this info in the file resurrect.g:

[[language]]
; File "r2d2_-_leg_left.gcode" resume print after print paused at 2018-03-21 14:53
M140 P0 S50.0
G10 P1 S245 R245
T1 P0
G10 P0 S225 R225
T0 P0
M98 Presurrect-prologue.g
M106 P0 S1.00
M106 P3 S0.00
M106 P4 S0.00
M106 P5 S0.00
M106 P6 S0.00
M106 P7 S0.00
M106 P8 S0.00
M106 S255.00
M116
M290 S0.000
G92 E0.00000
M83
M23 r2d2_-_leg_left.gcode
M26 S6360220 P0.000
G0 F6000 Z28.000
G0 F6000 X637.04 Y347.85
G0 F6000 Z26.000
G1 F3030.0 P0
M24

dc42

You may be able to resume the print when you have fixed the heater issue, but you will need to set up your resurrect-prologue.g file first. See https://duet3d.dozuki.com/Wiki/Setting_up_to_resume_a_print_after_a_power_failure.

FBG

I do M303 H1 S225 P0.5

M307 H1
Heater 1 model: gain 336.2, time constant 308.0, dead time 6.2, max PWM 0.50, calibration voltage 24.0, mode PID, inverted no, frequency default
Computed PID parameters for setpoint change: P26.3, I0.600, D114.5
Computed PID parameters for load change: P2

OLD value: M307 H1 A393.5 C296.9 D6.1 S0.60 V24.0 B0
New value: M307 H1 A336.2 C308.0 D6.2 S0.50 V24.0 B0

Something rare? I have 40W 24V e3dv6

dc42

The gain has gone down from 393 to 336, which is nearly 20%. That implies either that your heater has lost power, or that cooling of the hot end has increased. Check that the screws in the extruder heater terminal block on the Duet are still tight.

FBG

I see a thing….
the old value is with: M303 H1 S225 P0.6
the new value is with: M303 H1 S225 P0.5

is important this, or is indifferent?

dc42

Why are you using a PWM factor other than 1 when running M303? It's been standard to use full PWM when running M303 for several firmware versions.

FBG

This is incredible, now i do: M303 H1 S225 P0.5 and say:
Auto tune cancelled because target temperature was not reached

If i do: M303 H1 S225 say:
Warning: Heater 1 appears to be over-powered. If left on at full power, its temperature is predicted to reach 735C.
Auto tune heater 1 completed in 436 sec
Use M307 H1 to see the result, or M500 to save the result in config-override.g

Now the value in config-override is: M307 H1 A710.6 C318.6 D9.7 S1.00 V23.9 B0

dc42

Like many users, you have an over-powered hot end heater. You can still print with those values. For safety reasons you may wish to order a lower power heater cartridge.

FBG

I start the print again from the beginning, and after 20 hours now i can see than the temperature NOT is estable, why??
The first 20hours (aprox) is absolutely stable +/-1º and now with 30 hours:….

Now go from 216ºC to 233ºC

Of course same temperature is config in all print in 225º and only use T0
the value in config-override is: M307 H1 A710.6 C318.6 D9.7 S1.00 V23.9 B0

I don't have configured line M570 so i am frightened for the print, maybe go to give some error if the temperature continue fail?

Not errors show in console. I don't have fans or something than can cool the nozzle, chamber closed and same temperature in bed always

dc42

Undulating temperature usually means that the dead time parameter (D in M307) is too low. It could mean that the thermal contact between your heater cartridge and the heater block isn't as good as it used to be.

FBG

This extruder is used several months with arduino and marlin firmware without problems, i check the wires and thermal contact and absolutely ok.
The question is, Why after 20 hours start to fail?
I am thinking in use the M301 with PID parameters than i was use in the marlin firmware, instead of M303 system.
I don't finish to work perfectly with this M303 auto tuning

dc42

If it used to work but doesn't any more, then something must have changed. Your dead time parameter does look unusually high, suggesting that heat transfer from the heater cartridge to the heater block isn't as good as it should be. Values around 6 seconds are more usual for E3DV6 and similar hot ends. What type of hot end is it?

You could try running M303 tuning again and see if the dead time parameter has changed.