Fuse protection



  • I have a self built corexy with a rev 1.3 wifi clone.

    Its been set up and working for about a year now but I never got around to tidying the wiring. So now is the time.

    I use 24 volts and initially used a car audio 24 - 12v step down that was fuse protected with a 1A blade fuse. This allowed me to use 12v noctua fans.

    During a hotend unclogging I managed to short a fan out which blew the step down's 1A fuse. Replacing the fuse and all was good.

    I have now switched to 24v fans and as I think about proper wiring I'm reminded of that incident and wonder if I should use inline fuses between the fans and the controller board.

    Is this a good idea, and would the controller benefit from other powered components being inline fused?

    I have 5 steppers, 2 endstops, heater cartridge and a BLTouch. Also a SSR to switch my 240v heated bed.

    Thanks in advance.



  • While fuses are always good, the original Duet2 wifi has a fuse specifically for the fans so I would not bother duplicating it. Of course I don't know if your clone is fused.



  • What he said ☝

    Unless you can add more selective fuses there isn't much added value to the existing fan use when using fans powered via Vin.



  • @jens55 said in Fuse protection:

    While fuses are always good, the original Duet2 wifi has a fuse specifically for the fans so I would not bother duplicating it. Of course I don't know if your clone is fused.

    Thanks for the replies guys.

    It is fuse protected but I believe its a smc and so not easily replaced.


  • Moderator

    @Paddy The fan fuse was added with v1.03 of the Duet (see https://duet3d.dozuki.com/Wiki/Hardware_Overview#Section_PCB_revision_v1_Num_03) and should be a 1A mini-blade fuse, but with a clone, I don't know. Post a picture! I always like to see a clone, helps to identify them.

    Ian



  • @Paddy said in Fuse protection:

    It is fuse protected but I believe its a smc and so not easily replaced.

    That is a good point ..... as I found out when I accidentally shortened the wires and blew the fet. The fuse wasn't fast enough to protect the driver. Alas, there isn't much you can do about that if you are powering stuff from the Duet. I have had other instances where the fuses were fast enough and I am currently waiting for a hot air rework station for future screwups.
    I would think that the fet is easily replaced with a good soldering iron but so far I have just re-routed fan power through a different fan output.



  • Thanks guys.


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