Computer PSU Powerman ATX-250GTA Schematic?

[[email protected]]

This is an SPI power supply (powerman branded), I need the values to
two resistors which have burned out. They are located in the right
front corner near the corner mounting screw. One is flesh pink, the
other green. They are 1 watt carbon or metal film resistors. The only
bands I can make out on the pink are black and red (brown?) located on
either end. On the green one, the bands are red (brown)/black/red
(brown)/gold (Difficult to tell difference between the red and browns).
Is there a place where the schematic can be found, or someone
otherwise advise as to the values? I can get the identifiers, but
don't have them handy right now.

The resistors are not destroyed, the leads have corroded off them. I
can take readings and I get 6.8 ohms for the pink and 148.5 ohms for
the green. Does this tell me anything?

 

[Franc Zabkar]

This is an SPI power supply (powerman branded), I need the values to
two resistors which have burned out. They are located in the right
front corner near the corner mounting screw. One is flesh pink, the
other green. They are 1 watt carbon or metal film resistors. The only
bands I can make out on the pink are black and red (brown?) located on
either end. On the green one, the bands are red (brown)/black/red
(brown)/gold (Difficult to tell difference between the red and browns).
Is there a place where the schematic can be found, or someone
otherwise advise as to the values? I can get the identifiers, but
don't have them handy right now.

The resistors are not destroyed, the leads have corroded off them. I
can take readings and I get 6.8 ohms for the pink and 148.5 ohms for
the green. Does this tell me anything?

6.8 and 150 are preferred values.

- Franc Zabkar

 

[[email protected]]

The power supply, Powerman ATX-250GTA, failed. It is now only showing
power on the 3.3V rail, no 5V or 12V. This power supply is apparently
made by SPI (Sparkle) and was sold under a number of different brands
(ie AOpen), usually with the same model number. Upon inspection, three
3300uf/10V capacitors are leaking topside. R47 (green resistor
currently registering 148.5ohm) and R48 (pink resistor currently
registering 6.8ohm) each had one leg of their leads corroded off. You
can see the caps and resistors here:

http://pg.photos.yahoo.com/ph/smata67/album?.dir=/1724re2

or here:
http://depositfiles.com/files/41558/Burnt_Resistors.JPG.html
http://depositfiles.com/files/41562/Leaking_Jamicon_Caps.JPG.html

The burn hole is at R48 (pink resistor). The trace has lifted for
about .25" on the bottomside. The only remaining bands on this
resistor are what appear to be red (but could be brown) and black at
the extreme ends. Inner bands are faded. The green resistor has red
(again, maybe brown), black, red, and gold. I'm not familiar enough
with resistors to know whether they are carbon or metal film (I'm
leaning towards carbon) and their dimensions seem to indicate they are
1W.

 

[Dave D]

The power supply, Powerman ATX-250GTA, failed. It is now only showing
power on the 3.3V rail, no 5V or 12V. This power supply is apparently
made by SPI (Sparkle) and was sold under a number of different brands
(ie AOpen), usually with the same model number. Upon inspection, three
3300uf/10V capacitors are leaking topside. R47 (green resistor
currently registering 148.5ohm) and R48 (pink resistor currently
registering 6.8ohm) each had one leg of their leads corroded off. You
can see the caps and resistors here:

<snip>

Do yourself a favour and bin it. Buy a nice shiny new 400watt+ supply for a
few pounds/dollars/euros and have relative peace of mind. You will need to
replace all the electrolytics and isolate any other faults to get it back
working again, and you'll still have a crap, old, low power PSU which will
run hot and cook new parts like it has already done, possibly risking your
PC's components if the regulation fails.

Dave

 

[Mike]

Upon inspection, three
3300uf/10V capacitors are leaking topside ....
... leads corroded off.

See http://www.badcaps.net

I discovered three of these beasts inside my PC PSU, by chance. I'd opened
the PSU to change the fan (which was getting noisy) and just caught sight
of them hidden down in the cabling mess!

"YEC" branded 3300uf/10v capacitors, bulging tops, and brown crusty stuff
on the top. Removed and replaced with some new Panasonics. If you replace
the capacitors, make sure you get 105'C temperature rated, low ESR caps
that are designed for switch mode use.

If it's to the point where traces are being eaten off, then really do
consider a new PSU!

Mike.