Jump to content

Recommended Posts

Posted · Heated bed kit debug help

 

Just added a heated bed kit to a UM1. Unfortunately, I get no heat.

Everything else works (x/y/z, extrusion, nozzle heat and temp sensor). With bed temp set to zero, I get fine prints (on blue tape).

With bed temp set to 70, set point shows as 70, but measured temp stays 0. Bed stays cool.

The fact that bed reads 0, not ambient of ~20, makes me think more than one thing is wrong. If it was just the heater driver, I'd at least see ambient. If it was just a bad or disconnected temp sensor, the heater would go on (but possibly overheat).

Thermistor resistance is about 109 ohms at ambient. Heater resistance is about 3.7 ohms.

Help?

Paul

  • Link to post
    Share on other sites

    Posted · Heated bed kit debug help

    Thermistor resistance is about 109 ohms at ambient.

     

    Perfect. But where did you measure the resistance? Try measuring underneath the printer. Often you get an open where you screw down the wires on the bed or in the solder joints where the terminal block solders to the heated bed.

    Have you ever inserted a 4.7K resistor in the circuit board? If so you need to remove it. This detail is not mentioned I believe in the instructions.

     

  • Link to post
    Share on other sites

    Posted · Heated bed kit debug help

    Perfect. But where did you measure the resistance? Try measuring underneath the printer. Often you get an open where you screw down the wires on the bed or in the solder joints where the terminal block solders to the heated bed.

    Have you ever inserted a 4.7K resistor in the circuit board? If so you need to remove it. This detail is not mentioned I believe in the instructions.

     

    Thanks for the help. I never modified the main board. Could the resistor have come with the printer?

    I'm measuring on the exposed 90 pins that go to the thermistor connector on the PCB (see below). I'm getting 108.9 now.

    By the way, how do you disconnect the power supply from the heated-bed PCB? Once I connected it I can't seem to get it off. I see there is a slider on the end, but pushing it or pulling it still doesn't seem to release the connector. No big deal for now, but eventually it would be nice to be able to remove it.

    FullSizeRender.jpg

    I get 108.9 right now.

     

  • Link to post
    Share on other sites

    Posted · Heated bed kit debug help

    Perfect. But where did you measure the resistance? Try measuring underneath the printer. Often you get an open where you screw down the wires on the bed or in the solder joints where the terminal block solders to the heated bed.

    Have you ever inserted a 4.7K resistor in the circuit board? If so you need to remove it. This detail is not mentioned I believe in the instructions.

     

    Solved!

    The three wire jumper from the heated-bed kit PCB to the main board (temp3) is defective. 5v and Signal both have a good connection, but the middle (ground) is open (infinite resistance measured from the exposed pcb pin to the mainboard pin).

    Replaced that cable with three loose jumpers and I read 19C on the bed, and it heats up!

    I'll start a test print while I see if I can repair the jumper.

    Paul

     

  • 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

      • Help Us Improve Cura – Join the Ultimaker Research Program
        🚀 Help Shape the Future of Cura and Digital Factory – Join Our Power User Research Program!
        We’re looking for active users of Cura and Digital Factory — across professional and educational use cases — to help us improve the next generation of our tools.
        Our Power User Research Program kicks off with a quick 15-minute interview to learn about your setup and workflows. If selected, you’ll be invited into a small group of users who get early access to features and help us shape the future of 3D printing software.

        🧪 What to Expect:
        A short 15-minute kickoff interview to help us get to know you If selected, bi-monthly research sessions (15–30 minutes) where we’ll test features, review workflows, or gather feedback Occasional invites to try out early prototypes or vote on upcoming improvements
        🎁 What You’ll Get:
         
        Selected participants receive a free 1-year Studio or Classroom license Early access to new features and tools A direct voice in what we build next
        👉 Interested? Please fill out this quick form
        Your feedback helps us make Cura Cloud more powerful, more intuitive, and more aligned with how you actually print and manage your workflow.
        Thanks for being part of the community,

        — The Ultimaker Software Team
        • 0 replies
      • Cura 5.10 stable released!
        The full stable release of Cura 5.10 has arrived, and it brings support for the new Ultimaker S8, as well as new materials and profiles for previously supported UltiMaker printers. Additionally, you can now control your models in Cura using a 3D SpaceMouse and more!
          • Like
        • 18 replies
    ×
    ×
    • Create New...