Mini Duet 5+ - Part fan runs continuously

[PaulHew]

@t3p3tony I do not mind sending it back and paying for it to be fixed.
Not one for messing people around. I agree it was working, so no dispute there hence why I am offering to pay.

I have heard of mosfet's during my time on the forum, do not know what one looks like.

It did get hot in that little chamber so am going to go through the wiring to make sure all is good. It was hot enough to shrink the heat shrink cable labels near the extruder!

Appreciate the help as usual gents.
Regards,
Paul.

[T3P3Tony]

@paulhew drop me a line tony@duet3d.com and we can take it from there.

[NexxCat]

@t3p3tony Sorry to intrude, but does the Driver 0 TMC2209 look odd to you? Looking at 2 separate photos, the text line above GERMANY looks odd on that one driver.

[droftarts]

@nexxcat Yes, there does look like there's a hole burnt into it. @PaulHew does Driver 0 work okay? Is that where the extruder motor is connected?

Ian

[PaulHew]

@droftarts x and y are on 0 and 1, z on 3 e, on 4.

I will have another look later when I am back.

[PaulHew]

@paulhew it homed alright this morning.

[PaulHew]

@paulhew
As close I can get to driver0

Homing is fine and believe it or not it still extrudes!

[PaulHew]

Update....
I took the time last night to remove the Mini 5 from my printer so I can send to Tony. Thanks @T3P3Tony
Whilst at it I checked the fan cabling and found a melt spot on one of the cables. There was also a mark on the brass where i realize now it had shorted, me being inquisitive wiped it to see what it was!

As per the LDO part number and spec sheet which is above in this thread, 800ma is way too much for this little motor, even though they say it is rated for 1amp
The motor was that hot it burnt my fingers when checking the issue, in turn had heated the brass standoffs which then melted the sheath of the fan cable that was resting on the brass. (The whole lot is in a chamber)
Also you can see the heat shrink has been shrunk by the extreme heat. I put them on loose!

All the printers I have built and used the 80% rule, i have never had this.

However lesson learnt, replace chinese cable with silicone or use a protective braid.

For those who think I did not RTFM, I did and always do! Hence how I got into this mess!

[T3P3Tony]

@paulhew Thanks for the update. I think its likely that the melting + short fried the Out3 mosfet but will take a look when I get your board. The stepper driver "black spot" though we will see!

[PaulHew]

@t3p3tony Thank you for fixing my board, really do appreciate it.
Can start my tuning now and convert 'Voron' macros to work with RRF.

Thanks again
P.

[PaulHew]

Finishing Touch..... Love the new Duet Labels