Problem with PID-Tuning (RRF 3.4.0-b7)

Julian_Wicht

Hello,

I had last done a PID tuning in RRF3.0 or a bit earlier and by the post that there should be a new algorithm in RRF3.2beta3.2 or newer I did this PID again.

My old values in config-override.g were

; config-override.g file generated in response to M500 at 2020-08-18 09:33
; This is a system-generated file - do not edit
; Heater model parameters
M307 H0 A137.2 C650.1 D3.2 S1.00 V23.9 B0
M307 H1 A477.6 C169.6 D3.6 S1.00 V23.8 B0
M307 H2 A382.6 C148.6 D3.1 S1.00 V23.8 B0

Now I use the firmware version RRF 3.4.0-b7 and have done a PID tuning again with the following results (IDEX system)

M307 H0 R0.295 K0.200:0.000 D6.01 E1.35 S1.00 B0 ; PID tune for bed at 85c
M307 H1 R2.734 K0.423:0.102 D5.00 E1.35 S1.00 B0 V23.6 ; PID Tune for Hotend Left 240c
M307 H2 R2.503 K0.511:0.022 D5.11 E1.35 S1.00 B0 V23.6 ; PID Tune for Hotend Right 240c

On the following picture you can see a yellow line that I have drawn.
On the left of the line is an extreme fluctuation of the temperature with the results of the PID under the beta firmware.
To the right of the line is the old PID value which keeps a stable temperature.

alt text

Here is an excerpt from the Config.g for the heating elements

; Heaters
M308 S0 P"bedtemp" Y"thermistor" A"Bett" T100000 B3950             ; configure sensor 0 as thermistor on pin bedtemp
M950 H0 C"bedheat" T0                                              ; create bed heater output on bedheat and map it to sensor 0
M307 H0 B0 S1.00                                                   ; disable bang-bang mode for the bed heater and set PWM limit
M140 H0                                                            ; map heated bed to heater 0
M143 H0 S121                                                       ; set temperature limit for heater 0 to 120C
M308 S1 P"e0temp" Y"thermistor" A"X-Achse" T100000 B4725 C7.06e-8  ; configure sensor 1 as thermistor on pin e0temp
M950 H1 C"e0heat" T1                                               ; create nozzle heater output on e0heat and map it to sensor 1
M143 H1 S261                                                       ; Temperatur Limit
M307 H1 B0 S1.00                                                   ; disable bang-bang mode for heater  and set PWM limit
M308 S2 P"e1temp" Y"thermistor" A"U-Achse" T100000 B4725 C7.06e-8  ; configure sensor 2 as thermistor on pin e1temp
M950 H2 C"e1heat" T2                                               ; create nozzle heater output on e1heat and map it to sensor 2
M143 H2 S261                                                       ; Temperatur Limit
M307 H2 B0 S1.00

I don't think I did anything wrong, I used the following codes for the respective tools for the respective tools

M303 T0 S240
M303 T1 S240

Is there an error here with me or is it a firmware error?

best regards
Julian

Phaedrux

Can you share some details about the hotend and heaters? Fans? Nozzle socks? wattage?

Argo

@julian_wicht

There are already at least two more threads about the same issue so I don’t think it’s a user error.
You could check if the temperature is more stable by doing PID calibration as heater and not as a tool so there is no fan compensation involved. Looks like the fan compensation is overcompensation when using hotends that heater’s react fast.
What hotend are you using right now?

Julian_Wicht

@phaedrux

E3D V6 Hotend
24V 40W High Precision Heater Cartridges from E3D
V6 Silicone Socks from E3D
Fans on the Side are 24V Turbine Fan 40mm * 10mm 4010 DC Radial Cooling Fans
The Fans on the Front are for T0 30x30x10 and on T1 40x40x10
-- The Resion is on T0 i have installed a IR Sensor and it takes some Place (See Picture)
Nozzle on both are Original E3D 0,4 on T0 and 0,6 on T1

alt text

Julian_Wicht

@argo

i try it now with M303 H1 S240 to PID my Left Hotend

Auto tuning heater 1 completed after 3 idle and 5 tuning cycles in 341 seconds. This heater needs the following M307 command:
 M307 H1 R2.775 K0.438:0.000 D5.25 E1.35 S1.00 B0 V23.6
Send M500 to save this command in config-override.g

After i Try to Put the New M307 Command in the Console i got this message

M307 H1 R2.775 K0.438:0.000 D5.25 E1.35 S1.00 B0 V23.6
Warning: M307: Heater 1 predicted maximum temperature at full power is 417°C

and now if i try to Heat up Standby or Active Mode the heater not starting

If i put my old PID in the Console the Heater works again great

Julian_Wicht

I had not used the printer for the last few days and wanted to start it again today for a print job and wondered why the bed heater did not start.
Then I noticed that in the config-override.g file is still the new PID value for the heating bed.

M307 H0 R0.295 K0.200:0.000 D6.01 E1.35 S1.00 B0 ; PID tune for bed at 85c

After I changed this to the old PID as mentioned in the first post, the bed has also worked again.

M307 H0 A137.2 C650.1 D3.2 S1.00 V23.9 B0

Argo

@julian_wicht

Does it solve the jumping temperature issue though when PID calibrating your tool as a heater and not as a tool?

Julian_Wicht

@julian_wicht said in Problem with PID-Tuning (RRF 3.4.0-b7):

@argo
i try it now with M303 H1 S240 to PID my Left Hotend

It did not make a difference whether i PID via tool or heater, the result are now the Heater are not Starting