Unable to configure bed heater

Weevil · 23 May 2021, 04:06

My Duet is complaining about my bed heater taking too long to heat up. Note, in the past I had a separately powered heating pad. When it died, I decided to have a board control one.
I am using the original Duet 3 board (6HC) - firmware ver MB6HC 3.3RC2 (2021-05-11)
The power supply is 24V 500 watts
The bed heater is 24V 400 watts

This is my code (H0 is the bed heater):
M308 S0 P"temp1" Y"thermistor" T100000 B4138
M950 H0 C"out2" T0
M307 H0 B1 S1.00
M140 H0
M143 H0 S120
M308 S1 P"temp0" Y"thermistor" T100000 B4138
M950 H1 C"out1" T1
M307 H1 B0 S1.00
M143 H1 S280

I ran the heater configuration and followed the steps:
Auto tuning heater 0 completed after 5 idle and 9 tuning cycles in 1403 seconds. This heater needs the following M307 command:
M307 H0 B0 R0.300 C615.0 D1.30 S1.00 V22.7

I do that and get this message:
Heater 0 appears to be over-powered. If left on at full power, its temperature is predicted to reach 209C

I save with M500 anyway.

I even rebooted afterwards but still get this when I instruct via web control to heat the bed to 60
"Error: Heating fault on heater 0, temperature rising much more slowly than the expected 1.7°C/sec"

o_lampe · 23 May 2021, 06:00

@weevil
You have to read config-override by sending M501 at the end of config.g or in the Web interface.

Weevil · 23 May 2021, 12:40

@o_lampe I always had this just above the tools lines, near the bottom:

; Miscellaneous
M501
M911 S10 R11 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000"

engikeneer · 23 May 2021, 13:40

@weevil post your full config and config override using the </> code tags.
Looks like it's not reading the tuned parameters (1.7deg/s is the default for a heater)

Weevil · 23 May 2021, 14:14

@engikeneer You just gave me an idea. I'll try editing the M307 code.

Weevil · 23 May 2021, 14:21

@engikeneer EDiting the code directly didn't work either. It's still complaining.

Phaedrux · 23 May 2021, 19:57

post your full config and config override

Weevil · 23 May 2021, 20:39

@phaedrux config:

; Configuration file for Duet 3 (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Thu Feb 20 2020 16:55:51 GMT-0800 (Pacific Standard Time)

; General preferences
G90
M83
M550 P"MYTH3D"

M667 S1
M575 P1 B57600 S1

; Networking
M552 P192.168.1.19 S1
M553 P255.255.255.0
M554 192.168.1.1
M586 P1 S1
M586 P2 S1
M552 S1

; Drives
M569 P0.0 S1
M569 P0.1 S0
M569 P0.2 S1
M569 P0.5 S1
M569 P0.3 S1
M569 P0.4 S1
M584 X0.0 Y0.1 Z0.2:0.3:0.4 E0.5
M350 X16 Y16 Z16 E16 I1
M92 X80.00 Y80.00 Z400.00 E400.00
M566 X900.00 Y900.00 Z12.00 E120.00
M203 X6000.00 Y6000.00 Z180.00 E1200.00
M201 X500.00 Y500.00 Z20.00 E250.00
M906 X800 Y800 Z800 E800
M84 S30
M671 X-15:150:310 Y50:310:150 1S0.5

; Axis Limits
M208 X0 Y0 Z0 S1
M208 X300 Y300 Z500 S0

; Endstops
M574 X2 S1 P"io5.in"
M574 Y1 S1 P"io2.in"

; Z-Probe
M950 S0 C"io7.out"
M558 P9 C"io7.in" H5 F120 T6000
G31 P25 X-38 Y0 Z1.05
M557 X15:227 Y5:210 S50

; Heaters
M308 S0 P"temp1" Y"thermistor" T100000 B4138
M950 H0 C"out2" T0
M307 H0 B1 S1.00
M140 H0
M143 H0 S100
M308 S0 P"temp0" Y"thermistor" T100000 B4138
M950 H1 C"out1" T0
M143 H1 S280

; Fans
M950 F1 C"out7" Q500
M106 P1 S1 H T45
M950 F0 C"out8" Q500
M106 P0 S255

; Custom settings are not defined

; Miscellaneous
M501
M911 S10 R11 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000"

; Tools
M563 P0 S"MYTHprint" D0 H1 F0
M563 P0 D0 H1 F0
G10 P0 X0 Y0 Z0
G10 P0 R0 S0
T0

Config override

; config-override.g file generated in response to M500 at 2021-05-23 11:36
; This is a system-generated file - do not edit
; Heater model parameters
M307 H0 R0.299 C620.600:620.600 D1.28 S1.00 V22.7 B0 I0
M307 H1 R1.970 C184.600:184.600 D5.04 S1.00 V23.9 B0 I0
; Workplace coordinates
G10 L2 P1 X0.00 Y0.00 Z0.00
G10 L2 P2 X0.00 Y0.00 Z0.00
G10 L2 P3 X0.00 Y0.00 Z0.00
G10 L2 P4 X0.00 Y0.00 Z0.00
G10 L2 P5 X0.00 Y0.00 Z0.00
G10 L2 P6 X0.00 Y0.00 Z0.00
G10 L2 P7 X0.00 Y0.00 Z0.00
G10 L2 P8 X0.00 Y0.00 Z0.00
G10 L2 P9 X0.00 Y0.00 Z0.00

Phaedrux · 25 May 2021, 18:50

I would suggest deleting the config-override.g file and then re-run the heater tuning with M303 and when it completes use M500 again to save it, which should create a fresh config-override.g file.

Weevil · 25 May 2021, 19:23

@phaedrux I'll give it a shot.

Weevil · 26 May 2021, 12:53

@phaedrux That did not work. I got the following message:

Warning: heater behaviour was not consistent during tuning
Auto tuning heater 0 completed after 4 idle and 25 tuning cycles in 3679 seconds. This heater needs the following M307 command:
M307 H0 B0 R0.317 C276.8 D1.57 S1.00 V22.7
Send M500 to save this command in config-override.g

As with all tests, the beep alarm would go off each time the bed heats up. I went ahead and saved the code with M500 but the issue remains. I would be happy if I could just disable the alert. It appears to function fine.

Weevil · 26 May 2021, 13:27

@phaedrux I think the issue is the board is treating the bed heater like a nozzle heater. It is running tests with the fan on and fan off.

These codes:
M308 S0 P"temp1" Y"thermistor" T100000 B4138
M308 S0 P"temp0" Y"thermistor" T100000 B4138

They look identical. Perhaps there is a code for bed heaters.

Phaedrux · 26 May 2021, 17:56

@weevil said in Unable to configure bed heater:

I think the issue is the board is treating the bed heater like a nozzle heater. It is running tests with the fan on and fan off.

What M303 command are you using to tune the bed?

M303 T# will tune the heater as a tool with the fan
M303 H# will tune the heater as a heater without the fan

https://duet3d.dozuki.com/Wiki/Gcode#Section_M303_Run_heater_tuning

Weevil · 26 May 2021, 18:32

@phaedrux I thought I was using H. I'll double-check when I get home. But the M308 command, shouldn't the T100000 B4138 be different for bed?

engikeneer · 26 May 2021, 18:38

@weevil depends what thermistor you have. B4138 is the default the config tool uses so is almost certainly not right for your setup. You probably should find out the correct values for your thermistor (for both hotend and bed).
Having said that, it should only affect how accurate the measured temperature is (and probably won't make much difference at lower temperatures used by the bed).

Weevil · 26 May 2021, 18:40

@engikeneer The thermistor for my Keenovo pad is an NTC100K if that helps.
Also note, the heated bed size is 300x300.

Phaedrux · 26 May 2021, 19:19

@weevil said in Unable to configure bed heater:

The thermistor for my Keenovo pad is an NTC100K if that helps.

Chances are the B value should be B3950 in that case.

Weevil · 26 May 2021, 19:24

@phaedrux Thanks, I'll try that (fingers crossed).

Weevil · 27 May 2021, 00:33

@phaedrux M303 T# produces this error:
M303 H# tests with the fan
M303 T1 S60
Error: M303: tool 1 not found

theruttmeister · 27 May 2021, 02:28

@weevil said in Unable to configure bed heater:

@phaedrux M303 T# produces this error:
M303 H# tests with the fan
M303 T1 S60
Error: M303: tool 1 not found

Not surprising...

M563 P0 S"MYTHprint" D0 H1 F0
M563 P0 D0 H1 F0

You have configured Tool 0. There is no Tool 1.

Although I'm not sure why you are getting the fan running when the heater is.

Also you have a random H without a value:

M106 P1 S1 H T45

Doubt it's causing the problem, but can't hurt to fix.