Help to recover burned DuetWifi, it is posible

[spirit.robotics]

Hi everyone, Im building my CoreXY 30x30x42, everything was fine until now, Motors tested ok, BL tested OK, Heater tested ok, Heatbed with Mosfet ok, only remained the FANs for cooling the printing, and the always on for cooling the duet.

This is the machine

This is the board

Zooming into the fans

The machine was powered ON, boot ok, then after 30seg the fans dont still move, I move the cable and sudendly a smell and small fire here, I disconet but now look dead the board.

This is the burned part

Looking in detail, this chip had a hole, so is really dead

i have some questions

1- What funtion the dead chip do? now the board is dead, the board dont connect to wifi, even the paneldue and screen dont work, look bad
2- What I do wrong?
3- Any possibilities to recover the board, tonight I will take off the board from the machine to try connect by USB, I hope it work. Now only this led is on

https://youtu.be/g-4D7YqFQBo

4- I read all the info about in the web but dont find any info about this pins JUMPER EXT 5V EN and JUMPER INT 5V EN, which are at the side of the VAFN JUMPER SELECTION pin. In my Duet one of this pin have a bridge, I dont remember if I put there or not.

PLease any advise for what is this pins.

Any help wll be great, best

[alankilian]

@spirit-robotics

The chip U3 provides 5 Volts for the board.

Do you only see the Vin LED lit and not the 5 Volt or 3.3 Volt LEDs?

You can try supplying 5 Volts through the external 5 Volt supply connector.
https://duet3d.dozuki.com/Guide/2.)+Wiring+your+Duet+2+WiFi-Ethernet/9#s41

If you do not know why the fan had a short circuit I would not try supplying external 5 Volts. You will need to figure out that problem or it may cause more problems in the future.

[spirit.robotics]

@alankilian Thanks Alan, so if I put 5V external supply I can reuse the board? how I can do it?

[alankilian]

@spirit-robotics

Take a look at these two web pages and ask any questions you have.
https://duet3d.dozuki.com/Guide/2.)+Wiring+your+Duet+2+WiFi-Ethernet/9#s41
https://duet3d.dozuki.com/Wiki/Power_Wiring#Section_5V_power

[spirit.robotics]

@alankilian Great, I will do, How many Amps, I presume it is only for the logic of the board, paneldue and screen, 3 Ampers?

[alankilian]

@spirit-robotics The existing part U3 is designed for a maximum output at 5 volts of 2 Amps, so that's enough.

[spirit.robotics]

@alankilian OK, I will use a Mosfet LM 2596 to use 24V from the PSU and supply 5V to the board in EXT 5V, I hope it will rescue the board, pls let me know if you consider is good enough this mosfet. Best

[alankilian]

@spirit-robotics

Did you find out what caused the short-circuit?

If not, it will short-circuit again and damage something else.

[dc42]

@spirit-robotics when and where did you purchase the Duet? You may qualify for a replacement under warranty.

[spirit.robotics]

@alankilian Yes, the cause was a shorcut in one of the fans, I retired all the fan cables, so now the board cables are the ones working previous the issue

[spirit.robotics]

@dc42 I purchased in E3D in 2019, pre covid time. The board was working fine in a CoreXY I build earlier, but now I dissamble the machine to build a bigger CoreXY with tool changer, so I guest the warranty is off.

A question, the MOSFET maybe vary the voltaje between 4.9, 5.1 or 5,2? when a put the multimeter the voltaje is around 5V, but change a little... it is a issue of the multimeters or my supply? Finally, if the voltaje change a little will damage the board?

Best

[alankilian]

@spirit-robotics said in Help to recover burned DuetWifi, it is posible:

the MOSFET maybe vary the voltaje between 4.9, 5.1 or 5,2?

I don't know how much the Duet board needs exactly 5.0 Volts.

First, try putting a small load on the dc:dc converter and then measure the output voltage.

Sometimes when there is no load, converters don't do a good job with the voltage.

Add something like a 1,000 Ohm resistor across the outputs and them measure again.

[dc42]

@spirit-robotics anything between 4.5V and 5.5V will be OK.

[spirit.robotics]

@dc42 thanks

[spirit.robotics]

@alankilian ok, I will try

[spirit.robotics]

@spirit-robotics said in Help to recover burned DuetWifi, it is posible:

@alankilian ok, I will try

I connected with the mosfet, verified the voltajes, PINS, etc but dot start the board, still dead

I try with a direct USB connection, it works, the connection by pronterdace show alive the board, and the wifi connect, the screen still dnt work, I guest is insuficient ampers.

I think I can power the screen directly, maybe a need an small PSU 5V to power by the USB port the duet and directly the paneldue. Nice job... Any suggestions.

Best

[alankilian]

@spirit-robotics

Did you move the jumper from internal 5 Volts to external 5 Volts?

LINK.

Show us a photo of the LEDs.

[spirit.robotics]

@alankilian Yes, I did and check twice. I will remove the board for more test

[alankilian]

If you show which LEDs are lit it will help figure out if you have proper power before moving on to other things.

[spirit.robotics]

@alankilian HI

This is the Duet removed from the printer on EXT Power, all pins are in place as needed

I double check the PSU and the mosfet, they are delivering voltaje, the PIN EXT is in place, but is dead. I dont know why is dead, is supposed to be ON.

In USB power is ok, is working, the LEDs 5V, 3.3V and Wifi are ON, and can connect with pronterface and by web too

I was thinking use this small PSU from a old laser cutter and connect with a USB cable to the EXT IN and another connection, maybe, for the panel due