NTC3850 for Bed

samu_87

Hi wish configure my heated bed https://www.aliexpress.com/item/Funssor-400mm-12V-24v-250W-300W-Round-Polyimide-film-Heater-bed-NTC3950-Thermistor-for-DIY-Delta/32860129407.html?spm=a2g0s.9042311.0.0.2a7e4c4dEK9xG3 on my Duet WiFi but in my config file I thing there is something wrong because the web control say a temperature of 2000 degre, I have a PT100 on extruder 1 that is wired on bed output.

Someone can help me, because for me is not clear how to assign heaters and extruder.

This is my configurator file:

; Configuration file for Duet WiFi (firmware version 1.21)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v2 on Mon Mar 25 2019 12:03:15 GMT+0100 (CET)

; General preferences
G90 ; Send absolute coordinates...
M83 ; ...but relative extruder moves
M665 R283.5 L520 B200 H580 X0.0 Y0.0 Z0.0 ; Set delta radius, diagonal rod length, printable radius and homed height
M666 X0.0 Y0.0 Z0.0 ; Put your endstop adjustments here, or let auto calibration find them

; Network
M550 P"Delta" ; Set machine name
M551 P"samufree" ; Set password
M552 S1 ; Enable network
M587 S"XXXXXXX" P"XXXXXXXXXX" I192.168.1.230 J192.168.1.254 K255.255.255.0 ; Configure access point and IP addresses. You can delete this line once connected
M586 P0 S1 ; Enable HTTP
M586 P1 S0 ; Disable FTP
M586 P2 S0 ; Disable Telnet

; Drives
M569 P0 S1 ; Drive 0 goes forwards
M569 P1 S1 ; Drive 1 goes forwards
M569 P2 S1 ; Drive 2 goes forwards
M569 P3 S1 ; Drive 3 goes forwards
M350 X32 Y32 Z32 I1 ; Configure microstepping without interpolation
M350 E32 I1 ; Configure microstepping with interpolation
M92 X400.00 Y400.00 Z400.00 E855.00 ; Set steps per mm
M566 X900.00 Y900.00 Z900.00 E1200.00 ; Set maximum instantaneous speed changes (mm/min)
M203 X18000.00 Y18000.00 Z18000.00 E1200.00 ; Set maximum speeds (mm/min)
M201 X2000.00 Y2000.00 Z2000.00 E10000.00 ; Set accelerations (mm/s^2)
M906 X1200.00 Y1200.00 Z1200.00 E1000.00 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

; Axis Limits
M208 Z0 S1 ; Set minimum Z

; Endstops
M574 X2 Y2 Z2 S1 ; Set active high endstops

; Z-Probe
M307 H3 A-1 C-1 D-1 ; Disable heater on PWM channel for BLTouch
M558 P9 H30 F120 T3600 ; Set Z probe type to bltouch and the dive height + speeds
G31 P500 X24.25 Y-14 Z1.101 ; Set Z probe trigger value, offset and trigger height
M557 R190 S20 ; Define mesh grid

; Heaters
M140 H2
M305 P2 T100000 B4138 R4700 ; Set thermistor + ADC parameters for heater 0
;M143 H0 S120 ; Set temperature limit for heater 0 to 120C
M305 P0 X200 ; Configure thermocouple for heater 1
M143 H0 S280 ; Set temperature limit for heater 1 to 280C

; Fans
M106 P1 H-1
;M106 P0 S0.3 I0 F500 H-1 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned off
;M106 P1 S1 I0 F500 H1 T45 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned on

; Tools
M563 P0 D0 H0 S"EXTR" ; Define tool 0
G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
G10 P0 R0 S0 ; Set initial tool 0 active and standby temperatures to 0C

M912 P0 S3 ;Calibration CPU Temperature
M106 P2 T25:65 H100:101:102 L130 ;Cooling board

M204 P2000 T2000
M501

; Automatic saving after power loss is not enabled

; Custom settings are not configured

Many thanks!

dc42

@samu_87 said in NTC3850 for Bed:

; Heaters
M140 H2
M305 P2 T100000 B4138 R4700 ; Set thermistor + ADC parameters for heater 0

That looks OK except that you have B4138 where you probably want B3950. But that doesn't explain the problem. Suggestions:

Send M140 from the console amd check that it reports that the bed is using heater 2
Send M305 P2 from the console and check it reports the correct thermistor parameters
Check that you have the bed thermistor connected to the E1 thermistor input (not the bed thermistor input)
Check with a multimeter that the thermistor isn't open circuit.

samu_87

Hi, i made the 2 test:

1_1560163116178_Schermata 2019-06-10 alle 12.37.25.png 0_1560163116177_Schermata 2019-06-10 alle 12.37.45.png

Veti

just to make sure. which connector are you using for the thermistor on the duet board?

samu_87

@dc42 said in NTC3850 for Bed:

M305 P2 T100000 B4138 R4700

Ok, now I can read the temperature value, can you tell me the right parameter for the M305 command? Many thanks!

T3P3Tony

@samu_87 check out https://duet3d.dozuki.com/Wiki/Connecting_thermistors_or_PT1000_temperature_sensors#Section_Thermistors