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

    PWM Output 4-20mA

    Scheduled Pinned Locked Moved
    General Discussion
    3
    7
    434
    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.
    • andornotundefined
      andornot
      last edited by

      Is there any pwm outputs 4-20mA that i can use to control a phase angle controller to control IR strip lamps on the delta printer i am modifying ? The temperature control will be via a thermocouple.

      SpatialOne custom delta printer, upgrading to print PEEK, PEKK & Ultem

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

        You will need a PWM to 4-20mA converter for that. We designed and prototyped one for an OEM some time ago. I'll check whether we are allowed to publish the design.

        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

        andornotundefined 1 Reply Last reply Reply Quote 0
        • andornotundefined
          andornot @dc42
          last edited by

          @dc42 Thanks, if it cannot be published, is there anyway around it i have a phase angle controller from RS 232-9353

          SpatialOne custom delta printer, upgrading to print PEEK, PEKK & Ultem

          1 Reply Last reply Reply Quote 0
          • A Former User?
            A Former User
            last edited by

            this thins?
            https://docs.rs-online.com/0e21/0900766b8002e5be.pdf

            says it can be current and voltage controlled, so you might be able to use a 5v pwm output and just smooth it if need be.

            andornotundefined 1 Reply Last reply Reply Quote 0
            • andornotundefined
              andornot @A Former User
              last edited by

              @bearer How would i do this, i have limited experience in electronics?

              SpatialOne custom delta printer, upgrading to print PEEK, PEKK & Ultem

              1 Reply Last reply Reply Quote 0
              • A Former User?
                A Former User
                last edited by A Former User

                That is analogue electronics, or voodoo as its also called .. but I recon a RC filter set to a frequency well below the pwm frequency should work if the controller draw power doesn't draw power from the 4-20mA loop.

                Just ask google or youtube for a "RC low pass fileter" and see if you have any components that will work. For something like this it hardly matters if the cutoff is 10, 100 or 1000hz as you can set the pwm frequency on the duet to match whatever components you may have on hand.

                1 Reply Last reply Reply Quote 0
                • andornotundefined
                  andornot
                  last edited by

                  Spoken to supply of the Phase angle controller and 0 to 5V PWM input is capable. What pins can i use on the duet to give this output and how would it be coded?

                  SpatialOne custom delta printer, upgrading to print PEEK, PEKK & Ultem

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