Duet3D Logo Duet3D
    • Tags
    • Documentation
    • Order
    • Register
    • Login

    PT-100 temperature constantly at 2000 degrees after failure

    Scheduled Pinned Locked Moved
    Duet Hardware and wiring
    11
    54
    7.9k
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • dc42undefined
      dc42 administrators
      last edited by

      Does it read 2000 even with just usb power? If so then you have a bad connection, either in the wiring between the daughter board and the sensor, or the links you use for 2-wire connection are not working. Use a multimeter to check the wiring. The resistance of the sensor should should be a little over 100 ohms at room temperature.

      Duet WiFi hardware designer and firmware engineer
      Please do not ask me for Duet support via PM or email, use the forum
      http://www.escher3d.com, https://miscsolutions.wordpress.com

      1 Reply Last reply Reply Quote 0
      • gzcwnkundefined
        gzcwnk
        last edited by

        The other possibility that happened to me was electrical interference from the extruder stepper. So every time I fed filamenthe PT100 went to 2000C and tripped out on safety. To solve it I ran double shielded super flex microphone cable between the duetwifi and the PT100, no issues in 3+months. PS only earth it at the duetwifi end if you do this.

        1 Reply Last reply Reply Quote 0
        • CoolM8undefined
          CoolM8
          last edited by

          The issue still exists if only connect through USB. As this setup has worked before i don't think that there is any interference. I'm using the E3D PT-100 sensor but the strange thing is that i cannot measure any resistance not with the sensor that used to work nor with the new sensors that hasn't been used before. I have also another PT-100 sensor where i can measure its resistance to be around 100 Ohms, but the issue with the 2000 degrees still exists.

          1 Reply Last reply Reply Quote 0
          • T3P3Tonyundefined
            T3P3Tony administrators
            last edited by

            When you say you cant measure any resistance, is that with the PT100 connected to the daughterboard? if so then please try with it not connected to the daughterboard. At that point if it is not ~100R then you have a issue in the sensor or the wiring.

            www.duet3d.com

            1 Reply Last reply Reply Quote 0
            • CoolM8undefined
              CoolM8
              last edited by

              No, i cannot measure it when sensor is not connect to the daughterboard. But it seems still strange, it would mean I have two new E3D PT100 sensors that do not work? But even with the PT100 sensor from the Ultimaker Original where i can measure the resistance I sill have the same issue with the temperature reading. This would mean i have 2 issues at hand and even with the same setup that used to work before it went 2 times into failure. This is utterly strange.

              1 Reply Last reply Reply Quote 0
              • ShadowXundefined
                ShadowX
                last edited by

                Did you inspect the PWB board and connectors to make sure that none of the circuit traces are broken or if there is damage on the solder joint or connector?

                1 Reply Last reply Reply Quote 0
                • CoolM8undefined
                  CoolM8
                  last edited by

                  I don't see anything that any of the circuit traces are broken nor does anything look damaged.

                  With the reprapfirmwar tool i get this config for the E3D thermistor:

                  [[language]]
                  M305 P1 T100000 B4725 C7.060000e-8 R4700 X201 ; Set thermistor + ADC parameters for heater 1 and remap it to channel 201
                  
                  

                  But i also tried everything else even:

                  [[language]]
                  M305 P1 X201
                  
                  
                  1 Reply Last reply Reply Quote 0
                  • dc42undefined
                    dc42 administrators
                    last edited by

                    Do you have the PT100 connected to the first or second channel on the daughter board? 201 is the second channel, the first is 200.

                    Duet WiFi hardware designer and firmware engineer
                    Please do not ask me for Duet support via PM or email, use the forum
                    http://www.escher3d.com, https://miscsolutions.wordpress.com

                    1 Reply Last reply Reply Quote 0
                    • CoolM8undefined
                      CoolM8
                      last edited by

                      Right now i have on the second channel. As I've said, it used to work on channel 1 until the failures and since then it doesn't even work on channel 2.

                      1 Reply Last reply Reply Quote 0
                      • dc42undefined
                        dc42 administrators
                        last edited by

                        Do you have a resistor of between 100 and 200 ohms that you can connect to the terminal block in place of the PT100?

                        Duet WiFi hardware designer and firmware engineer
                        Please do not ask me for Duet support via PM or email, use the forum
                        http://www.escher3d.com, https://miscsolutions.wordpress.com

                        1 Reply Last reply Reply Quote 0
                        • CoolM8undefined
                          CoolM8
                          last edited by

                          No i don't have a resistor around but i think this won't make a difference. Since the Ultimaker Original has a measurable resitance of around 100ohms. It measures like in the image below (the green connection has around 110 ohms):

                          It seems to me that the issue is with the daughter board or the duet itself.

                          1 Reply Last reply Reply Quote 0
                          • dc42undefined
                            dc42 administrators
                            last edited by

                            Do you have anything else connected to the SPI bus, for example a ribbon cable connecting the CONN_SD port on the Duet to the PanelDue for using a second SD card?

                            If the answer is no, please ask your supplier for a new daughter board.

                            Duet WiFi hardware designer and firmware engineer
                            Please do not ask me for Duet support via PM or email, use the forum
                            http://www.escher3d.com, https://miscsolutions.wordpress.com

                            1 Reply Last reply Reply Quote 0
                            • CoolM8undefined
                              CoolM8
                              last edited by

                              Well, I've ordered a new daughter board but i still get the same issue. And no I've nothing connected to SPI bus. There is no PanelDue nor a second SD card.

                              1 Reply Last reply Reply Quote 0
                              • dc42undefined
                                dc42 administrators
                                last edited by

                                Have you removed the PT100 sensor from the hot end or is it still installed? I'm wondering whether it may have developed a short between the element and the case.

                                Duet WiFi hardware designer and firmware engineer
                                Please do not ask me for Duet support via PM or email, use the forum
                                http://www.escher3d.com, https://miscsolutions.wordpress.com

                                1 Reply Last reply Reply Quote 0
                                • CoolM8undefined
                                  CoolM8
                                  last edited by

                                  It's the same even if installed in the hotend or not. If I read the voltage on the middle 2 pins I get a reading of about 2V with the E3D PT100 and about 0.2V for the Ultimaker PT100. With both those voltages i get 2000 degrees in the Frontend.

                                  1 Reply Last reply Reply Quote 0
                                  • dc42undefined
                                    dc42 administrators
                                    last edited by

                                    The 0.2V with the Ultimaker sensor sounds plausible, the 2V with the E3D one sounds like an open circuit sensor, or else it's a thermistor not a PT100.

                                    If you send the M305 P1 X201 command from the Gcode Console, does it return an error message?

                                    Duet WiFi hardware designer and firmware engineer
                                    Please do not ask me for Duet support via PM or email, use the forum
                                    http://www.escher3d.com, https://miscsolutions.wordpress.com

                                    1 Reply Last reply Reply Quote 0
                                    • CoolM8undefined
                                      CoolM8
                                      last edited by

                                      It is all fine when I send M305 P1 X200 or X2001, no error message whatsoever. It even turns off the fan shortly that is set to start at 40 degrees but that runs continuously now because of the 2000 degrees.

                                      1 Reply Last reply Reply Quote 0
                                      • dc42undefined
                                        dc42 administrators
                                        last edited by

                                        What voltage do you read across the outer 2 pins of the 4 pin terminal block? It should be the same 0.2V that you get across the inner ones, with the good PT100 connected.

                                        Duet WiFi hardware designer and firmware engineer
                                        Please do not ask me for Duet support via PM or email, use the forum
                                        http://www.escher3d.com, https://miscsolutions.wordpress.com

                                        1 Reply Last reply Reply Quote 0
                                        • CoolM8undefined
                                          CoolM8
                                          last edited by

                                          Yes the outer 2 pins show 0.2 V as well. I really don't get this, why did it used to work and now nothing helps? There is nothing burnt or damaged on the duet itself.

                                          1 Reply Last reply Reply Quote 0
                                          • dc42undefined
                                            dc42 administrators
                                            last edited by

                                            My best guess is that the SPI bus isn't working but I'm puzzled that there is no error message. Do you have anything connected to the expansion connector?

                                            Duet WiFi hardware designer and firmware engineer
                                            Please do not ask me for Duet support via PM or email, use the forum
                                            http://www.escher3d.com, https://miscsolutions.wordpress.com

                                            1 Reply Last reply Reply Quote 0
                                            • First post
                                              Last post
                                            Unless otherwise noted, all forum content is licensed under CC-BY-SA