Dead PSU PS-6271-6DG Part Identification

[juergenb]

Hi,

i have a PSU from a Dell 7010, the Resistor R604 is blown.
I have taken a Picture from the Label and the Location on the pcb.

On the Label you can see the blown part.

I haven´t found any schematics in the net, maybe someone has this power supply open and could help me.

Thanks

Jürgen

[R_J]

Re: Dead PSU PS-6271-6DG Part Identification

The value could be marked on the resistor, what are the markings on it? I suspect it is a low value, If it is open, I suspect the transistors connected to it are shorted.

[juergenb]

Re: Dead PSU PS-6271-6DG Part Identification

The value was (is) marked on the resistor.
But the resistor has been damaged.

Maybe someone knows the value or even better, has a PS-6271-6DG and could take a picture.

Jürgen

[russell1981]

Re: Dead PSU PS-6271-6DG Part Identification

i am not sure; but its look like 81 ohm to me.

[juergenb]

Re: Dead PSU PS-6271-6DG Part Identification

This resistor must be around .1-2 Ohms / 1 Watt.

This resistors are for safety and they must take the switching current from the Transistors.

This might be several AMP's and with 81 Ohms
i think i might have a light bulb in my PSU...

[CapLeaker]

Re: Dead PSU PS-6271-6DG Part Identification

I think it is higher than 2 Ohms, but not 81 Ohms high either. I'd say more like something like 15 to 21 Ohms. Based on what ever is left over from that resistor, I'd stick a 20 Ohm resistor in it and see what happens.
If that resistor is toast, that transistor connected to it is bad too. Also check the gate drive.

[budm]

Re: Dead PSU PS-6271-6DG Part Identification

Did you trace out to see how that resistor is connected in the circuit?
It looks to be Resistor for the Source pin of that power MOSFET mounted on the heatsink.
MOSFET is not shorted out?
Can we see good clear straight shot of the top and the bottom side of the board?
BTW, you can also try measuring the resistance between that exposed body against each end of the resistor to see what it shows as.