Setting up heater chamber - need help

JoergS5

@felt342 chamber heater documentation https://duet3d.dozuki.com/Wiki/Connecting_and_configuring_a_chamber_heater is without M307, I expect M307 has an expected temperature timeout according to heatblock and bed heating up, which is faster than chamber. But I didn't find anything yet.

Maybe M307 C parameter higher, because you will need more than 2 minutes to heat up the chamber.

I found a good documentation of the M307 parameters which can help: https://duet3d.dozuki.com/Wiki/Tuning_the_heater_temperature_control#Section_Setting_the_model_parameters_manually
Setting C higher seem to be a good try.

felt342

@JoergS5 I saw this and I first what I used to check why I don't see any difference between dead time 5 and 2000 is this:

M307 H5 ; report model parameters for heater 5, and whether the model is being used

And it did report me this:

	M307 H5
Heater 5 model: gain 340.0, time constant 140.0, dead time 5.5, max PWM 1.00, calibration voltage 0.0, mode PID, inverted no, frequency default
Computed PID parameters for setpoint change: P13.4, I0.482, D51.4
Computed PID parameters for load change: P13.4

Then in my config-override is a completely different story for Heater 5.

If I do M307 H1 then it reports correct numbers from config-override corresponding to Heater 1.

Why it might happen?

Trying with higher C now..

JoergS5

@felt342 the config-override is loaded if you have M501 in your config (in most cases at the end of the config). I would comment the M307 H5 in override out until solved in config.

The D parameter seems to be a delay time "The D parameter is the dead time, which is the delay between a change in PWM and an appreciable effect on the rate of temperature change.", so in my understanding better set it low.

felt342

@JoergS5

I did remove M501 from config.g, and if I use now M370 H5 to report PID values, its show me again something wrong..

M307 H5
Heater 5 model: gain 340.0, time constant 140.0, dead time 5.5, max PWM 1.00, calibration voltage 0.0, mode PID, inverted no, frequency default
Computed PID parameters for setpoint change: P13.4, I0.482, D51.4
Computed PID parameters for load change: P13.4

this is my config.g

; General preferences
G90                                             ; send absolute coordinates...
M83                                             ; ...but relative extruder moves
M550 P"own"                                     ; set printer name

M667 S1                                         ; select CoreXY mode

; Network
M552 S1                                         ; enable network
M586 P0 S1                                      ; enable HTTP
M586 P1 S0                                      ; disable FTP
M586 P2 S0                                      ; disable Telnet

; Drives
M569 P0 R-1
M569 P0 S1                                      ; physical drive 0 goes forwards
M569 P1 S1                                      ; physical drive 1 goes forwards
M569 P2 S1                                      ; physical drive 2 goes forwards
M569 P3 S1                                      ; physical drive 3 goes backwards
M569 P4 S1                                      ; physical drive 4 goes forwards
M584 X4 Y1 Z2 E3:0                             ; set drive mapping
M350 X16 Y16 Z16 E16:16 I1                      ; configure microstepping with interpolation
M92 X200.8 Y200.8 Z400.5 E415:415		; set steps per mm
M566 X900 Y900 Z20 E2000.00:2000.00      	; set maximum instantaneous speed changes (mm/min)
M203 X15000 Y15000.00 Z200 E13000.00:13000.00   ; set maximum speeds (mm/min)
M201 X1000 Y1000 Z100 E3000.00:3000.00      	; set accelerations (mm/s^2)
M906 X1300 Y1300 Z1500 E600:600 I30             ; set motor currents (mA) and motor idle factor in per cent
M84 S90                                         ; Set idle timeout

; Axis Limits
M208 X-16 Y0 Z0 S1                                ; set axis minima
M208 X321 Y208 Z305 S0                        ; set axis maxima

; Endstops
M574 Z1 S2                		     ; set active low and disabled endstops
M574 X1 S0                			  ; set active high endstops
M574 Y2 S0

; Z-Probe
M307 H3 A-1 C-1 D-1                             ; disable heater on PWM channel for BLTouch
M558 A10 S0.005 P9 H3 F60 T5000 R0.3                          ; set Z probe type to bltouch and the dive height + speeds
G31 P25 X-10 Y-47.06 Z-0.19                  ; set Z probe trigger value, offset and trigger height (positive value brings bed closer)
M557 X0:290 Y-45.952:190 S20                      ; define mesh grid

; Heaters
M141 H5 					; heater 5 is the chamber heater
M305 X1 P5 B4725 C7.060000e-8 			; heater 5 is monitored by a E3D thermistor
M307 H5 A70 C600 D2000 S1.00 V0.0 B1	; use bang-bang control for the chamber heater
M307 H0 B0 S1.00                        	; disable bang-bang mode for the bed heater and set PWM limit
M305 P0 T100000 B4138 R4700             	; set thermistor + ADC parameters for heater 0
M143 H0 S150                            	; set temperature limit for bed heater 0 to 150C
M305 P1 X200                                    ; configure PT100 for heater 1
M143 H1 S480                                    ; set temperature limit for heater 1 to 480C
M305 P2 X201                                    ; configure PT100 for heater 2
M143 H2 S300                                    ; set temperature limit for heater 2 to 300C

; Fans
M106 P0 S0 I0 F20 H-1                          ; set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned off
M106 P1 S1 I0 F20 H-1                          ; set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned off
M106 P2 S1 I0 F20 H-1                          ; set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned off

; Tools
M563 P0 S"Left" D0 H1 F-1                       ; define tool 0
G10 P0 X0 Y0 Z0                                 ; set tool 0 axis offsets
G10 P0 S0 R175 									; Set tool 0 active and standby temperatures
M563 P1 S"Right" D1 H2 F-1                      ; define tool 1
G10 P1 X20.09 Y0 Z0                               ; set tool 1 axis offsets
G10 P1 S0 R175 									; Set tool 0 active and standby temperatures

; Custom settings are not defined

; Miscellaneous
                                           ; load saved parameters from non-volatile memory

Higher C did not work.

JoergS5

@felt342 please try setting D low (see my text change).

I expect the values to be changed after a reboot only or setting it differently explicitly.

felt342

@JoergS5

Okay, there is some light -

I did set D value to 1, and for some reason, if I report M307 H5 its does show me values from the config.g finally!

And start to autotune however it seems didn't change anything.

JoergS5

@felt342 is the error message Error: Heating fault on heater 5, temperature rising much more slowly than the expected 1.7°C/sec gone now? Would be interesting how the 1.7 is calculated. Then we can understand how to set it higher.

felt342

@JoergS5 I just did a test and got now this error with 0.3C/s

Error: Heating fault on heater 5, temperature rising much more slowly than the expected 0.3°C/sec

Could be what my value for E3D thermistor are wrong? But those values is something that I found on duet forum for e3d thermistor.

JoergS5

@felt342 can you see how 1.7 and 0.3 is calculated? M307 original and now)?
I found the error message in the source code, it depends on expected rate, dead time, the current temperature and the PWM.

Measuring the temperature wrong could be a reason.

I've also seen 4725 as value for the E3D thermistor. You could try verifying that it works by heating up somehow without the chamber heater. (hair dryer)

felt342

@JoergS5

Well, setting C value to 2000 doesn`t give me an error anymore about Fault in heater 5, and its keeps the rising temperature. But I still can not do the autotune.

Yeah the thermistor seams works.

JoergS5

@felt342 you get the same autotune error like in the first post? And does the reported temperature value of the thermistor go up?

felt342

@JoergS5

Yes, this is an error:

Autotune canceled because the temperature is not increasing.

Temperature goes up, but slowly about 1 degree a minute. This would be fine for me because I am planning to add two heaters there overall of 600, but first I got one and would like to deal it up first, to at least heating without errors. Which we did now (thanks to you!) setting C to 2000, but to perform autotune for real values would be better.

JoergS5

@felt342 Seems to be a timeout. I cannot find the error message in the source at the moment.

felt342

@JoergS5

Yeah, I really appreciate your help and digging in! What I am thinking is maybe better to move thermistor to the middle of the chamber, it will probably be the faster response until I have only one heater.

JoergS5

@felt342 Now I know why I cannot find it. I search in the 3.1.1 code....

=> didn't find it in 2.05 code also. Will search and will tell you if I find something.

felt342

@JoergS5

Happens
Thank you!

JoergS5

@felt342 I found it in pid.cpp of 2.05 source:

// Heating up
{
const bool isBedOrChamberHeater = reprap.GetHeat().IsBedOrChamberHeater(heater);
const uint32_t heatingTime = millis() - tuningPhaseStartTime;
const float extraTimeAllowed = (isBedOrChamberHeater) ? 60.0 : 30.0;
if (heatingTime > (uint32_t)((model.GetDeadTime() + extraTimeAllowed) * SecondsToMillis)
&& (temperature - tuningStartTemp) < 3.0)
{
platform.Message(GenericMessage, "Auto tune cancelled because temperature is not increasing\n");
break;
}

So the error message is called and a break occurs, if the heating time is bigger than dead time + extraTimeAllowed.

A low dead time helps in any case.

extraTimeAllowed is defined by:
const float extraTimeAllowed = (isBedOrChamberHeater) ? 60.0 : 30.0;
so for Chamber it is 60.
You could try setting D negative, say -59. Don't know whether it works.

You're welcome and I wish you success with the heated chamber!

felt342

@JoergS5

That seems working without error!
I didn't try negative D, but I set D to 1 and kept C at 2000, waiting for autotune and values

Thanks a lot again!

JoergS5

@felt342 Nice to hear, thank you!
See you.

felt342

@JoergS5

I must say it`s a nice way of solving the issue, digging the source code, will take it as a tip