Shorted fan connector on Duet 3, VIN fuse & MOSFET blown
quite a misfortune but unfortunately by trying to connect multiple LEDs via an adapter board, I shorted OUT9 on the Duet 3. OUT7+8 were also connected to the adapter board at that time but seem to look okay. No other components were connected (except the Raspberry Pi which also still works). After a visual inspection, only the VIN_FUSE and the MOSFET (?) of OUT9 seem to be blown, see the following photos.
If you wanna check for any other blown components, feel free to analyse the board.
Is there maybe a risk that any other components are blown? How can I check if the rest of the board still works?
I don't mind being short of one fan connector but the fuse makes it impossible to use the whole Duet and I don't wanna throw away a 250€ piece of junk because of 2 faulty components.
I see a lot of similar threads for the Duet 2 Wifi but what about the Duet 3? Is the blade fuse of VIN easily fixable? Where do I find a compatible replacement (im EU based)?
Thanks for any help!
Edit: In case I just need to replace the fuse and that's it, I see a potential problem with "out-of-tolerance" fuses as described in this thread. How do I make sure they have the right tolerances?
Can I maybe safely test the Duet by supplying power via the SBC or USB?
Yes you can check what powers up by connecting via USB. Follow along with this: https://duet3d.dozuki.com/Wiki/What_to_do_if_your_Duet_won't_respond
If the fuse is blown it would need to be replaced obviously. You can pull it and check it for continuity with a multimeter.
I believe the Duet3 is using the same 1A mini blade fuse as the Duet2. Usually can be found at automotive/motorcycle supply places.
As for what else to check and repair options, @dc42 or @bearer would have a much better idea than me.
@TechNi, it's likely that just the mosfet has failed and the fuse blown. It's a standard "mini blade fuse".
The diagnosis LED blinks in its usual 0.5s intervals and I was also able to access Duet Web Control via the SBC.
Just a last question about the fuse because there seems to be some disagreement. @Phaedrux is talking about a 1A fuse, here I read about 10A for V_Fused (and 15A for the bed even though they're the same color) and the blue ones I find on Amazon are also usually 15A fuses. So which one is it?
Not sure if the exact rating matters but the different specifications are a bit confusing. Is it even possible to use a 20A fuse if I need more juice for the motors?
As shipped the MB6HC has blue 15A fuses in both positions.
It's most unlikely that you will exceed 15A through the VIN fuse, bearing in mind that most of the time the current draw from VIN of each motor driver will be many times lower than the current flowing in the motor.
@Phaedrux is talking about a 1A fuse
Sorry, my brain skipped the 5. Must have been thinking of the 1A fan fuse on the duet2.