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

    IR sensor faulty readings after crash

    Scheduled Pinned Locked Moved Solved
    IR Height Sensor
    3
    14
    590
    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.
    • teteleundefined
      tetele
      last edited by

      Let me know if you need any specific angle. And thanks!

      2021-01-14 22.35.23.jpg 2021-01-14 22.35.17.jpg

      1 Reply Last reply Reply Quote 0
      • Phaedruxundefined
        Phaedrux Moderator
        last edited by Phaedrux

        Is there some thing missing at C1 in lower left?

        Is this a DC42 IR sensor or a clone?

        Z-Bot CoreXY Build | Thingiverse Profile

        1 Reply Last reply Reply Quote 0
        • teteleundefined
          tetele
          last edited by

          C1 is empty, there are only blank solder pads there. I don't exactly know if it's a clone or not, I got it in a BLV MGN Cube kit, like I said.

          1 Reply Last reply Reply Quote 0
          • Phaedruxundefined
            Phaedrux Moderator
            last edited by

            e3b80f0a-7f18-4d1d-9167-b04fb4b31b9b-image.png

            C1 is populated in this image of the Duet IR sensor.

            Z-Bot CoreXY Build | Thingiverse Profile

            1 Reply Last reply Reply Quote 0
            • Phaedruxundefined
              Phaedrux Moderator
              last edited by

              Maybe the emitter or sensor got nudged a bit too, so it's detecting the surface from two different heights because the emitters don't converge anymore. Just a guess.

              https://miscsolutions.wordpress.com/mini-height-sensor-board/

              See the modifications section.

              Z-Bot CoreXY Build | Thingiverse Profile

              1 Reply Last reply Reply Quote 0
              • teteleundefined
                tetele
                last edited by tetele

                It's super plausible that my board is a clone, but that does not explain why it used to work and now it doesn't. There was never a capacitor or any other SMD part at C1.

                I think that the only thing that got knocked in the crash was the large electrolytic capacitor, but there is a chance it might have moved the sensor a bit, as it was bent towards the left.

                Be that as it may, my optical components are SMD so the barbaric plier technique does not apply 😁

                But thanks a lot for trying to help!

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

                  Make sure that the electrolytic capacitor is the same size as the original and mounted flush to the board. Its primary purpose is to block light passing directly from the IR emitters to the IR sensor. The value doesn't matter but the size does.

                  C1 is not supposed to be fitted.

                  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

                  teteleundefined 1 Reply Last reply Reply Quote 0
                  • teteleundefined
                    tetele @dc42
                    last edited by

                    @dc42 thank you! That makes a lot of sense, as the old capacitor was pried from the board, leaving light through.

                    At the moment, the one I re-soldered is neither the same size as the original, nor flush with the board. I didn't realize that it's used to block light.

                    Can you tell me if I can use a different voltage or capacity? I do have other capacitors that are thicker, but only in different specs.

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

                      Yes, as long as the voltage rating is at least 6.3V (preferably at least 10V) you can use a different value. We have used both 10uF and 22uF in production.

                      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

                      teteleundefined 1 Reply Last reply Reply Quote 0
                      • teteleundefined
                        tetele @dc42
                        last edited by

                        @dc42 Thanks a lot! I don't have any larger replacement on hand, I need to order some. Would creating a shroud or any opaque barrier between the emitters and receiver help? I could simply try to stick the capacitor closer to the board, you can hopefully see it's not that far away or that small.

                        2021-01-15 10.50.47.jpg 2021-01-15 10.48.41.jpg

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

                          Yes an opaque barrier should work.

                          The capacitors we use in that position include Farnell part# 9452389 and RS part# 706-0488. They are 5mm high x 5mm diameter with 2mm lead spacing.

                          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
                          • teteleundefined
                            tetele
                            last edited by

                            Holy crap, it seems to have worked! I soldered the capacitor flush with the board and it seems to be triggering only in the 2-4mm range. I used my 4x7mm capacitor that I had on hand, but the main thing was to make sure light does not bleed under it.

                            Probably that's what happened when the old one got knocked, a slit was formed under it that allowed the light to pass, even if the electrical connections were not broken.

                            Thanks a lot @dc42!

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