MOSFET Resolved

  • Hi just a quick question so as not to risk seeing smoke rise from my duet wifi.
    I have an exsternal power supply for my heat bed, 24V 480w, connected to my mosfet which in turn is connectied to my heat bed.
    The question is the mosfet control is connected to the duet wifi via the heated bed ouput 15Amps or is there another connector which I can not find?
    reading around haven't found something thta completly answers my question.

    OK found this
    "You can use a solid state relay (SSR) to switch the bed heater by connecting its control terminals to the Duet bed heater terminals. " so i guess that means yes to my question.
    If so the why do I get not voltage out put on the connector when I turn the heat on?

    OK all works my fault one of the control wire was not making a good contact.


  • So how exactly did you connect gate, drain and source of the mosfet? I'm not using a mosfet module but just a mosfet to 220 package and a bit confused

  • If you are using an external mosfet module you can connect it to the heated bed output. I do. But it won't draw 15a, more like 50mA. You could in theory use another pin and save your heated bed output for some other purpose, you don't really need two mosfets in series, but it's easier this way.

Log in to reply