Upgraded to 3.2, had a bad curve fit on a heater autotune
Here is the output of the console (backwards in time):
1/17/2021, 2:12:31 AM Warning: Auto tune of heater 1 failed due to bad curve fit (R=1.548, 1/C=0.0056:0.0050, D=9.3) 1/17/2021, 2:08:05 AM Auto tune starting phase 3, fan on 1/17/2021, 2:04:42 AM Auto tune starting phase 3, fan off 1/17/2021, 2:01:44 AM Auto tune starting phase 2, heater settling 1/17/2021, 1:58:17 AM Auto tune starting phase 1, heater on 1/17/2021, 1:58:12 AM M303 T0 S215 Auto tuning heater 1 using target temperature 215.0°C and
PWM 1.00 - do not leave printer unattended
The previous model from well over six months ago, but updated by an M500 command:
M307 H1 R2.044 C129.200:129.200 D5.70 S1.00 V12.8 B0
I haven't attempted to do it again because it is getting late, and just wanted some feedback if this is something that might change by running it again.
It is not the negative deadtime another search for this issue had.
The printer is a delta printer, duet wifi (early version), V6 connected to a Smart Effector, PT1000 sensor.
Do you have a heater block sock installed? Is the fan duct pointing directly at the block? Was it at room temp when you started?
The values from 6 months ago will still work and you can stick with them. Running the tuning again when you get a chance to see if it happens again would be helpful to know.
Something rather interesting happened yesterday. When I went to do another test it heated up to target temperature and then cooled down naturally. The test never completed and I couldn't get the heater to heat up again.
So now, I try to heat it up and have a fault. I reset it, and jiggle the wires a bit as I tell it to heat again. It does so.
I do not know if these are related but will be taking a closer view at the wires of the heater. The printer has been sitting for some time and went through a house move.
It just worked after I redid the entire wiring and seating and got:
Auto tuning heater 1 completed after 3 idle and 10 tuning cycles in 731 seconds. This heater needs the following M307 command:
M307 H1 R1.701 C224.5:193.5 D8.77 S1.00 V12.8
Quite different than the original.
Not that far off really. The question is, are the temps stable?