Suspect Bad PS Apple AcBel API 1PC36

[Toasty]

Re: Suspect Bad PS Apple AcBel API 1PC36

Seriously doubt it's C30.

[thestitch]

Re: Suspect Bad PS Apple AcBel API 1PC36

Hi, Toasty !

After several days of severe testing the PSU under very
nasty thermal condition... yes, it`s rock stable again ! ! !
Put 4 (!) 15k SCSI HDs in and connected an 22" ADC Display to ATI 9800,
after appx. 90 starts no PSU failure :-)

Faulty cap was C30 in this PSU.

Thanks
willy

[Chevy2]

Re: Suspect Bad PS Apple AcBel API 1PC36

I have the same PSU, same symptoms, but the white 25V lead is shorted. Any ideas what I should check?

[Toasty]

Re: Suspect Bad PS Apple AcBel API 1PC36

Regulator.

[Chevy2]

Re: Suspect Bad PS Apple AcBel API 1PC36

Sorry, it's been a while since I've done any electronic components repair (other than just replacing bad caps). Do you know which one I should try to replace first or the quick process to track down the bad one? Thanks.

[Toasty]

Re: Suspect Bad PS Apple AcBel API 1PC36

You are stating that the 25v line is shorted. What makes you say that?

[Chevy2]

Re: Suspect Bad PS Apple AcBel API 1PC36

Looks like the 25v was me and some bad soldering. That part is fixed now. I get 5v trickle and 25 volts, but no trickle 12 v like I should per the link below. I have one 2200uf that looks fine, that I haven't replaced yet, should I go ahead and change it out too? The PSU fans spin and turn off when I push the power button.

http://www.jcsenterprises.com/Japama...EB2C04619.html

[Toasty]

Re: Suspect Bad PS Apple AcBel API 1PC36

Best read that pinout again.

[Chevy2]

Re: Suspect Bad PS Apple AcBel API 1PC36

Looked it over again. They made it sound like the 12v was a trickle. Since the PSU fans spin up and quickly turn off when pushing the power button (motherboard lights up too) and I have 25v and 5v trickles, which caps would you recommend replacing next?

The motherboard boots fine btw. I tested with a PC supply and an adaptor that I made.

[Toasty]

Re: Suspect Bad PS Apple AcBel API 1PC36

See Posts #11 & 119.

[Chevy2]

Re: Suspect Bad PS Apple AcBel API 1PC36

Thanks Toasty...appreciate the help!

[Chevy2]

Re: Suspect Bad PS Apple AcBel API 1PC36

See Posts #11 & 119.

Toasty, thanks for taking the time to help me out. C43 and the secondaries were the issue and it's working perfectly now.

[Toasty]

Re: Suspect Bad PS Apple AcBel API 1PC36

Great! Was just going to ask how you made out. Glad you got it working!

[stevenA]

Re: Suspect Bad PS Apple AcBel API 1PC36

Thanks to all of your posts (especially Toasty and his lessons) I have just recapped a G4 MDD PS and solved the long running problem that it would only start with an ADC display connected.

For info, the bad caps were:

C16
C21
C29
C43
C60
C32
C45
and maybe C30 which was out of limits for my tester.

Said otherwise, all of the Teapo's removed had failed, and some of the L-Tec's. I suspect that the start up problem was linked to C32 or C45, although this is only a suspicion - either way, they all needed replacing as smoothing caps can cause bigger issues in the long term!

Thanks again

[stevenA]

Re: Suspect Bad PS Apple AcBel API 1PC36

Thanks to all of your posts (especially Toasty and his lessons) I have just recapped a G4 MDD PS and solved the long running problem that it would only start with an ADC display connected.

For info, the bad caps were:

C16
C21
C29
C43
C60
C32
C45
and maybe C30 which was out of limits for my tester.

Said otherwise, all of the Teapo's removed had failed, and some of the L-Tec's. I suspect that the start up problem was linked to C32 or C45, although this is only a suspicion - either way, they all needed replacing as smoothing caps can cause bigger issues in the long term!

Thanks again

After finishing the job and testing, I QC'd the components used and recorded actual results - as you will see in the attached, I actually used the wrong component for C35 - I had intended to use a UCC KY but had multiple caps and made the mistake. Hopefully should not be critical as this is a smoothing cap

[frantal]

Re: Suspect Bad PS Apple AcBel API 1PC36

Hi, my G4 MDD (dual 1,25) did not turn on, nor the power button on the monitor ADC. So I recapped on the PSU C43 (100uF/25) and C60 (1000uF/10). Now the light on power button of ADC monitor turn on, but no chime and no life signs on the computer. Besides this it is very difficult to know where the critical caps are located. I bought all the caps in the list "MDD PS Replacement Caps as Used 20th Oct-2.pdf", but until now only 2 substituted. Could you suggest me where to find the critical on the list, if you have just done this work? I attached label type of PSU and the side where I think there are the "critical" caps. Many thanks for the help...

[Toasty]

Re: Suspect Bad PS Apple AcBel API 1PC36

Here is my drawing from several years ago. Hope it helps!

T

[frantal]

Re: Suspect Bad PS Apple AcBel API 1PC36

many thanks!! I will go to do this work....

[frantal]

Re: Suspect Bad PS Apple AcBel API 1PC36

Many thanks for the drawings. It made me the work shorter! Now all works again!! I checked with ESR/Capacity meter and only 2 caps gave me bad measures, the small ones (0,47uF and 47 uF. The other seemed still good. In any case now PSU is renewed!!

[Kansas Sparks]

Re: Suspect Bad PS Apple AcBel API 1PC36

Finally, the correct thread... Thanks again Toasty! Much higher resolution file is available if you'd like. Just email me. I'll most likely be in touch again, once I crack open a Samsung PSU for clarifications on a similar line-art project. Cheers!