Power control for duet 3



  • Hello,

    I recently got myself a duet 3 and I am relatively new to (DIY) 3d printing and electronics. I have a few questions regarding wiring setup and running of the board.

    1. After a print is done, is there a safe shutdown practice for the duet 3? Or killing the main power is the way to go?

    2. I would like to have an on/off switch between the PSU and duet3 board, but I am kind of confused how to implement the required hardware.

    Usually what is the max. current drawn by the duet 3? Can I connect an on/off switch in series? Or should I consider a SSR with the input signal coming from the on/off switch?

    Or else is there any other method to achieve the following result, on/off switch to power duet 3 board and once printing completed using m-command to power off only the duet 3.

    I would like to get the community's experienced advice and ideas regarding this.

    Thank you. 🙂



  • @kvi94 said in Power control for duet 3:

    After a print is done, is there a safe shutdown practice for the duet 3? Or killing the main power is the way to go?

    depends if you have a raspberry pi connected. In that case you need to initiate the linux shutdown.

    otherwise you can just shut off the power (i would still avoid shutdown while files are written to the sd.ie file upload)

    I would like to have an on/off switch between the PSU and duet3 board, but I am kind of confused how to implement the required hardware.

    just wire something like this
    https://images-na.ssl-images-amazon.com/images/I/81MCFMTYabL.AC_SL1500.jpg
    to the power inputs of the duet.

    Or else is there any other method to achieve the following result, on/off switch to power duet 3 board and once printing completed using m-command to power off only the duet 3.

    for this you would need an external 5v supply that is always on
    and something like this
    http://doc.3dmodularsystems.com/ps_on-kit-assembly/



  • @Veti said in Power control for duet 3:

    for this you would need an external 5v supply that is always on
    and something like this
    http://doc.3dmodularsystems.com/ps_on-kit-assembly/

    Thanks for the prompt response and the link. That is exactly what i was looking for.

    however, why do i need a ext 5v supply that is always on?

    Based on the schematic provided, the momentary switch should be actuated long enough for the board to signal the SSR to close and hence the switch can be released. If i am not wrong...



  • @kvi94 said in Power control for duet 3:

    however, why do i need a ext 5v supply that is always on?

    the 5v powers the cpu, so that you can actually issue the command. without power how would the duet run?



  • @Veti said in Power control for duet 3:

    @kvi94 said in Power control for duet 3:

    however, why do i need a ext 5v supply that is always on?

    the 5v powers the cpu, so that you can actually issue the command. without power how would the duet run?

    Alright, that is the case if i use a SBC. Sorry, forgot to mention for now i will be using it in standalone mode.

    Additionally, would a SSR rated 25amps be an overkill?

    Thank you.



  • @kvi94 said in Power control for duet 3:

    Additionally, would a SSR rated 25amps be an overkill?

    Buy a quality SSR, do not source one from china or your house will catch on fire.

    Omron G3NA-210B-DC5 (10A) or Crydom D2425 (25A) or Crydom 84134000 (10A) SSR




  • Moderator

    I think those would both be suitably overkill for switching DC power to the Duet. Nothing wrong with that.



  • Personaly, I always aim for overkill when speccing SSRs. The only things you need to watch out for are leakage current and sometimes minimum load current.

    Also, note that a high current SSR is generally only good for that current when it's on a humungous heatsink. Without said heatsink, it might only do a third of that. Having 3x in hand is about what I'll normally aim for, but I rarely put them on much of a heatsink - normally only a thickish aluminium mounting plate.

    Actually, that Crydom says it will do 12A without heatsink.

    As noted up thread, more than 99% of the SSRs on Ebay are fake. Don't buy them. They might not burn your house down, but I wouldn't bet on it.



  • Crydom and Schneider Electric are both reliable brands. I would add that amazon has a big counterfeit product problem as well.


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