Jump to content
Ultimaker Community of 3D Printing Experts

new thermistor consider in firmware?


Recommended Posts

Posted · new thermistor consider in firmware?

Hi at all,

i beg you to help me!

i use a arduino mega 2560 and would like to conect a new thermistor to my ultimaker, instead of the one, which is in the printerhead with the nozzle. the wires were no problem, but when i try to connect my pc to the ultimaker with the new thermistor i get a deficiency report.

If i understood some posts correct, i have to change something in the firmware.

Is this correct? And if so, what i have to change?

the new thermistor is this one:

http://www.electronic-things.de/shop/RepRap-Shop/Mechanik/Hot-Ends/NTC-Thermistor-100K---5.html

thanks!

sandy

 

  • Link to post
    Share on other sites
    Posted · new thermistor consider in firmware?

    Don't know where to find a table for that thermistor. Not all 100K thermistors are the same.

    According to this:

    http://media.digikey.com/pdf/Data%20Sheets/Honeywell%20Sensing%20&%20Control%20PDFs/135-104LAF-J01.pdf

    The beta is 3974. T0=25C, R0=100000 ohms.

    Knowing that you can calculate resistance at different temps here:

    http://www.reprap.org/wiki/MeasuringThermistorBeta

    Then calculate the needed table with this information:

    http://www.reprap.org/wiki/Thermistor#Calculating_Thermistor_Beta_.2F_Rz_Values

    then insert the resulting table into the Marlin firmware in the file thermistor tables.h

    Then read instructions on how to build Marlin (the easiest step in tall this but will still take an hour). google "how to build marlin for arduino". Lots of instructions in many places such as here:

    http://wiki.ultimaker.com/Marlin_firmware_for_the_Ultimaker

    and here:

    http://www.solidoodle.com/how-to-2/how-to-update-firmware/

    But don't use that version of marlin. Use the ErikZalm version.

     

  • Link to post
    Share on other sites
    Posted · new thermistor consider in firmware?

    There's already a thermistor table entry for the 'Honeywell 135-104-LAF-J01' which is only off by one letter from the one you're using.... no idea what the difference might be, but maybe they are compatible. To use it, you need to change this line in Marlin's configuration.h file:

    #define TEMP_SENSOR_0 -1

    to 7 instead of -1.

    Since this is a thermistor, not a thermocouple, do you also need to add a pull-up resistor to the motherboard? or is that only for other sensor channels when adding a heated bed? And is the interface board on the printhead no longer needed? I admit I'm almost clueless on the temp sensing hardware, so I'm kinda confused on the specifics...

     

  • Link to post
    Share on other sites
    Posted · new thermistor consider in firmware?

    Good catch. They use the same tables, so that's great. The only difference is that the LAF is more accurate: 5% instead of the LAG which is 10%. This table probably assumes a 4.7K pullup but it doesn't say.

    So now all you have to do is build marlin and change configuration.h to use temp sensor 7 as shown above.

     

  • Link to post
    Share on other sites
    Posted · new thermistor consider in firmware?

    Hey Guys, I grabbed out that thread cuz I got a question about this topic.

    We have a pt100 for the hotend and a pt100 for the heatbed and we wanna connect them directly to that Board V1.5.7.

    On our Board there seem to be already those 4.7k Resistors. Are we doing fine connecting those PT100 directly to the "Temp1" and "Temp2" marked connectors just with GND and Siganal?

    Do we have to make those changes on

    #define TEMP_SENSOR_0 X

    #define TEMP_SENSOR_1 X

    X: Sensor used here.

    Greets and thank you for ya help.

  • Link to post
    Share on other sites
    Posted · new thermistor consider in firmware?

    Problem solved.

    Just connected Hotend to "Temp0" and Heatbed to "Temp2".

    In Marlin

    #define TEMP_SENSOR_0 X

    #define TEMP_SENSOR_1 X

    X for the used thermistor.

    Greets.

  • Link to post
    Share on other sites

    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now
    • Our picks

      • Talking additive | The 3D printing podcast
        Why should we be the only ones asking questions? Join us and ask Jabil all your questions on September 22nd 5pm CET
          • Like
        • 3 replies
      • Ultimaker masterclass: Optimizing your Ultimaker Cura workflow
        Save your seat for either broadcast on September 23.
        What will you learn?
        · Best practices for iterative print preparation and every lesson you should learn from each print
        · The right way to use per-object settings and when they are most useful
        · Easy-to-use resources for anyone who wants to develop their own printer definitions, plugins, or print profiles
        · How to optimize print profile settings and whether to “keep” or “discard” changes
        · When is the right time to export your drawing from CAD? (Based on Ultimaker Cura’s surprising power as 3D control software)
        · And a whole lot more tips and tricks!
         
        How can I join?
        This free masterclass will take place twice:
        1. 11am CEST (5pm SGT, 5am EDT)
        2. 5pm CEST (11am EDT, 8am PDT, 11pm SGT)
          • Like
        • 0 replies
      • Do you use 3D printing at work? Let us know
        It doesn't matter if you are using 1 Ultimaker or 10, there is inspiration in everything. We're looking for ...
        • 1 reply
    ×
    ×
    • Create New...