Bed Heater fault [3.4.B5]

SIam

Hello,

first the good news, the motor idle timeout works with this firmware Thank you for your great work !!!

Now The bad News After a successful new PID Tuning, my Heater for the bed goes again into error mode

2021-09-29 09_31_09-hypercube.png

One thing noticed me After the PID Tuning, the Shown Settings are Different with the saved one (M500)

The console result is:

M307 H0 B0 R0.473 C290.7 D0.90 S1.00 V24.3

and this will be inserted into config override

M307 H0 R0.473 C290.692:290.692 D0.90 S1.00 V24.3 B0 I0

I don't think that this is the Problem, but only a "beauty error"

greets

Andy

SIam

@siam
here are the log with modified D Value from 0.9 up to 2.5 the fluctuation from the heat bed is now max. 0,1 C°

PWM.txt

SIam

@siam the issue is with 3.4.b5 the same

T3P3Tony

@siam to confirm, the issue is that you still can't tune you bed and arrive at a working set of M307 parameters. I was not sure what the log of D values Vs PWM was for?

SIam

@t3p3tony said in Bed Heater fault [3.4.B5]:

to confirm, the issue is that you still can't tune you bed and arrive at a working set of M307 parameters.

that's right, the PID Tuning is working and when I use this result to heat the bed I got after every 10 - 20 C° the heater fault.

I was not sure what the log of D values Vs PWM was for?

As far I have understood @dc42 , should the PWM value be stable with the computed PID settings but in my case this isn't so

jens55

@siam, I get occasional heater errors on the bed with a fully tuned bed. Not enough to warrant a full investigation. The error only happens on heat up of the bed from cold. 3.4b4

PCR

@jens55 3.4b4 should have resolved this i think. But i am still getting errors @dc42

T3P3Tony

@pcr are you getting the same error? i.e. the bed faults because its heating too slowly?

PCR

@t3p3tony yes.

T3P3Tony

@pcr please send the M307 command that the tuning suggested

SIam

I hope that I have not bored you, but the Heater fault does still persist in 3.4.b6
after the PID Tuning with 3.4.b6 I got this result:

M307 H0 B0 R0.460 C286.3 D0.90 S1.00 V24.3

and here is the old known error message:

6.11.2021, 19:31:14	Error: Heater 0 fault: at 53.2°C temperature is rising at 0.1°C/sec, well below the expected 0.3°C/sec

T3P3Tony

@siam I am not sure why the tuning is reporting the bed can heat at 0.46 deg/s but is only heating at 0.1 deg/s can you try changing your M307 command to lower the R parameter (try R0.3).

SIam

@t3p3tony said in Bed Heater fault [3.4.B5]:

I am not sure why the tuning is reporting the bed can heat at 0.46 deg/s but is only heating at 0.1 deg/s

then there are two of us

If I reduce the R value, The Problem is gone, but I think that this is not the solution maybe (or better Hopefully) I'm wrong, but I think if the final rrf3.4 is out with this PID algorithm more people will have this problem.

T3P3Tony

@siam can you post an image of the temp graph that point at which you get the fault, and let me know the target temperature. That way we can see if it's faulting when the PID may be slowing the heating rate to not overshoot, or during the main section of full power heatup.

SIam

@t3p3tony Sorry for The delay I had last week, a small working accident. I recorded a Video from The heating Process, you can find the heating error at 1:20 min. 2:40 min. and 4:10 min.

https://kleinersonnenschein.eu/heaterror.mp4 if you need more tests, let me know!

T3P3Tony

@siam thanks that's helpful.

I measured the first minute of your video the bed heater raised by 17.7 degrees in 60 seconds so that is an R of 0.295 so Changing R to 0.29 is a good idea.

Once you have done that, If you don't mind recording a M303 tuning for the bed that would be super helpful. I am curious why the tuning is suggesting an R of 0.46

SIam

@t3p3tony with R0.29 the heating was successful! Now I have to wait for cooldown of the bed, and then I will start the PID tuning I think this I can do this tomorrow

SIam

@t3p3tony and here is a video from the PID tuning process https://kleinersonnenschein.eu/pidtuning.mp4

btmcmahan

Hey @SIam Did you find a solution for this? I've having the same problem with firmware 3.4.0. After reading this thread, I think I can tweak my R#, but this seems like a band-aid not a real solution. Obviously I would prefer if Auto-Tune gave me working values.

Skan

Did anyone fix this issue? I am having the same issue with my large bed