Whatsminer M3X PSU Repair

[mavazov]

Hi
I have a broken PSU unit of M3X which is P5-12-2200-V1 . i send it to one of my repair-shop of my city and after a long time he couldn't fix it. he removed some ICs from back of PCB and lost it.before i send it to him i got picture of PCB so i can notice the difference of changes. but i just got picture of front of PCB not Back. so can anyone post a picture of back of pcb?
i searched and find noting of picture of pcb in the internet so i post my picture when board was functional maybe help anyone in the future.

https://i.imgur.com/W2iZXPG.jpg
https://i.imgur.com/7N9oc9x.jpg
https://i.imgur.com/45S5Fan.jpg

[BitMaxz]

I can't find any images of this PSU in Google and Bing.

You just want to see the image of the back if what the IC look like?

I think contacting the manufacturer may solve the issue why not try to request a PCB diagram of this PSU unit from this email micro@microbt.com

[philipma1957]

I can direct you to this link

https://pangolinminer.com/support/spare-parts/

but the psu = $$

https://pangolinminer.com/product/p5-power-supply-unit-for-m3x-shipout-in-7-days/

a used unit is less

https://pangolinminer.com/product/m3x-2ndh/

[mavazov]

I can direct you to this link

https://pangolinminer.com/support/spare-parts/

but the psu = $$

https://pangolinminer.com/product/p5-power-supply-unit-for-m3x-shipout-in-7-days/

a used unit is less

https://pangolinminer.com/product/m3x-2ndh/

Thanks but i can't buy used or new PSU anymore. its because of my country condition.


Hi
good news almost!
i get deep into it and i could turn it on but instead of 12V it give 10V . i hook it up and miner couldn't start.
so i send it to local repair shop and he troubleshoot it for me and find that 3 of N-Channel Mosfets blow Heatsink at the end of PCB and 1 gate control of those Mosfets are missing. and he couldn't do anything. but when i get it back from him i realized that the PCB Transformers is kind of mirror to each other so i found the mosfets and gate driver part number. the  SG40N01LQ is N-channel Mosfet but i couldn't find it on the internet. its all Chines! it was also hard to find any datasheet but i found it!

N-Channel PDFN 5*6-8L，ID , 100A
VDSS , 45V
RDS(ON), 2mΩ (max.) @ VGS=10V
RDS(ON), 2.5mΩ (max.) @ VGS=4.5V

so with digikey.com i found a similar part (TSM020N04LCR) and ordered from china that hasn't arrived yet.
the gate driver was IR4427S and i ordered it too.

Here is the pictures : https://imgur.com/a/apH7op9

now i have two questions : why after the transformers are Mosftes? shouldn't be a diode to rectify?
and is 10V issue has any connection to those Mosfets? you know if i replace those will it work or it has other problem?

[lightfoot]

The MOSFETs are switchers, if one is blown the supply may work at a reduced voltage.

Look for the blown one. In circuit you should be able to test for resistance between gate and source and between gate and drain. One will be different, replace it.

And nice job figuring this out. The FETs are what usually generate the most heat, so they blow up. Don't forget heat sink compound on them when replacing!

[mavazov]

The MOSFETs are switchers, if one is blown the supply may work at a reduced voltage.

Look for the blown one. In circuit you should be able to test for resistance between gate and source and between gate and drain. One will be different, replace it.

And nice job figuring this out. The FETs are what usually generate the most heat, so they blow up. Don't forget heat sink compound on them when replacing!

Thanks Man!

[joberns]

Hi man, i know im a couple month too late but i had a similar issue and as an electrician myself i did some test, i took entry voltage =good, output zero....
Then at first i took the multimeter to check if the big Transformer were getting the voltage but nada...
Then after a last look bit on despair side ... i've seen that familiar rubber cylindar  near the plug and of course the protection fuse had busted and  after cutting the rubber carefuly , you could see easy.I just cut near board very carefuly the wire which was quite tick and done a descent size soldering operation with a wire jumping from the plug wire to the board itself.
Worked like a charm and been pushing the asic to the limit and so far nothing went wrong.(that machine went  with vibration stuck  near the installation wall and fan got blocked but always be carefull, protection fuse dont blow for no reason and if you bypass it and you dont know why it has busted, next time its a scrap psu and even fire risk .Best will be to go the the electronic store get a remplacement and there is cheap fuse holder .

Well always look at the fuse protection at first even if it quite hidden in M3X under that thick rubber, because 2200W psu remplacement are expensive for this old whatsminer.

I hope it help or if you already know all that , your a boss man .
(im french so dont hate me for my grammar lol)

Peace

[lightfoot]

Nice Job! Not sure why the fuse blew, but yes replace it with a fuse and holder and you should be in business. Sometimes they just used cheap fuses.

Congratulation, and mine like hell!