How to use temperature value of hotend of 3d printer in arduino

alperensari1 · June 16, 2023, 9:06pm

i am totally new in this forum, so i'm sorry if i opened this topic with some mistakes.
i want to make filament from plastic bottles. in order to do that i bought some components. i have 1 stepper motor nema17, mos module, l298n motor driver, a hothend which came from a 3d printer. my problem is i dont know how to use hothends temperature value in arduino. this hothend have 4 pins. 2 of them for vcc and gnd, and the other 2 is temperature. i couldn't figure it how to transfer this value to arduino.i tried connect that pins to analog pins in arduino but it gives mi random values.i attached two picture of hotends. i'm sorry if it asked before .

DaveX · June 16, 2023, 9:11pm

3D printer hotends typically use a 100K NTC thermistor, and need a voltage divider to translate their varying resistance into a readable voltage, along with some code to translate the voltage curve into temperature.

Do you have any specifications on the thermistor?

alperensari1 · June 16, 2023, 9:30pm

Thanks for reply.
I didnt do any spesifications. its how i took from printer. is it enough to use 10k resistor. Did i understand correct?

Railroader · June 16, 2023, 10:37pm

There's a high risk those things are not compatible. Please post a link to the datasheet of the stepper.

Please post schematics showing the connections and voltages involved.

DaveX · June 16, 2023, 11:41pm

Is it a thermistor? Does it have a resistance near 100K (or 10K?) at room temperature?

How do you have it connected?

https://www.petervis.com/electronics%20guides/calculators/thermistor/thermistor.html

Do you know the thermistor's Beta? or Steinhart-Hart coefficients? If you can measure temperature, you can fit them:

Working temperatures for PET would be around 250C, which is out of spec for cheaper thermistors.

david_2018 · June 17, 2023, 1:06am

Do you know which particular 3D printer the hotend came off of? That might give you some idea of what type thermistor you have.

alperensari1 · June 23, 2023, 8:00pm

Anet et5x

DaveX · June 23, 2023, 10:07pm

Looks like

points to:

GitHub - SkyNet3D/anet-board: This is a board definition which works in Arduino IDE 1.8.x for Anet Board targets. points to

which mentions:

which says it's configured for:

github.com

thijsk/Skynet3d/blob/fde3ed2179905beeb39e04e80d71095cb005c29a/SkynetV2.3.2/Configuration Profiles/Anet A8/A8- fullgraphicsLcd- no autolevel/Configuration.h#L220


      
          * Temperature sensors available:
          *
          *    -3 : thermocouple with MAX31855 (only for sensor 0)
          *    -2 : thermocouple with MAX6675 (only for sensor 0)
          *    -1 : thermocouple with AD595
          *     0 : not used
          *     1 : 100k thermistor - best choice for EPCOS 100k (4.7k pullup)
          *     2 : 200k thermistor - ATC Semitec 204GT-2 (4.7k pullup)
          *     3 : Mendel-parts thermistor (4.7k pullup)
          *     4 : 10k thermistor !! do not use it for a hotend. It gives bad resolution at high temp. !!
          *     5 : 100K thermistor - ATC Semitec 104GT-2 (Used in ParCan & J-Head) (4.7k pullup)
          *     6 : 100k EPCOS - Not as accurate as table 1 (created using a fluke thermocouple) (4.7k pullup)
          *     7 : 100k Honeywell thermistor 135-104LAG-J01 (4.7k pullup)
          *    71 : 100k Honeywell thermistor 135-104LAF-J01 (4.7k pullup)
          *     8 : 100k 0603 SMD Vishay NTCS0603E3104FXT (4.7k pullup)
          *     9 : 100k GE Sensing AL03006-58.2K-97-G1 (4.7k pullup)
          *    10 : 100k RS thermistor 198-961 (4.7k pullup)
          *    11 : 100k beta 3950 1% thermistor (4.7k pullup)
          *    12 : 100k 0603 SMD Vishay NTCS0603E3104FXT (4.7k pullup) (calibrated for Makibox hot bed)
          *    13 : 100k Hisens 3950  1% up to 300°C for hotend "Simple ONE " & "Hotend "All In ONE"
          *    20 : the PT100 circuit found in the Ultimainboard V2.x

So maybe its a 100K thermistor intended for a 4.7K sensing resistor.

where that Marlin implementation uses this interpolation table:

github.com

thijsk/Skynet3d/blob/fde3ed2179905beeb39e04e80d71095cb005c29a/SkynetV2.3.2/thermistortable_5.h#L27-L59


      
          const short temptable_5[][2] PROGMEM = {
            {    1 * OVERSAMPLENR, 713 },
            {   17 * OVERSAMPLENR, 300 }, // top rating 300C
            {   20 * OVERSAMPLENR, 290 },
            {   23 * OVERSAMPLENR, 280 },
            {   27 * OVERSAMPLENR, 270 },
            {   31 * OVERSAMPLENR, 260 },
            {   37 * OVERSAMPLENR, 250 },
            {   43 * OVERSAMPLENR, 240 },
            {   51 * OVERSAMPLENR, 230 },
            {   61 * OVERSAMPLENR, 220 },
            {   73 * OVERSAMPLENR, 210 },
            {   87 * OVERSAMPLENR, 200 },
            {  106 * OVERSAMPLENR, 190 },
            {  128 * OVERSAMPLENR, 180 },
            {  155 * OVERSAMPLENR, 170 },
            {  189 * OVERSAMPLENR, 160 },
            {  230 * OVERSAMPLENR, 150 },
            {  278 * OVERSAMPLENR, 140 },
            {  336 * OVERSAMPLENR, 130 },

This file has been truncated. show original

alperensari1 · June 27, 2023, 6:17pm

thanks for all replies. that link helped me. I found a 10k resistor and use it exactly same with the link. And it worked. thanks a lot.

system · December 24, 2023, 6:18pm

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.

Topic		Replies	Views
How to just control stepper motor and hotend temperature of 3D printer extruder? General Guidance	5	4263	May 5, 2021
Temperature sensing project , newbie asking for help Nano Every	6	633	September 22, 2022
How to use NTC 100k thermistor to measure high temperature? Sensors	14	38206	May 6, 2021
Dead Thermistor? Programming	6	581	July 12, 2021
Temperature difference from two thermistors General Guidance	6	1094	May 5, 2021

How to use temperature value of hotend of 3d printer in arduino

Related topics