AcBel 360W PSU Project

[MacOS Plus]

Today I went ahead and replaced capacitors on my AcBel 360W with only the current ones I had on hand.  Here are my observations:

  C10 and C21 in mine are 10mm diameter rather than the 12.5mm noted in the original parts list.  I don't know if that was an error in the reference or if my PS is a different revision.  Factoring in those and the other correction FDB made to the list, I had parts on hand to change C10 (the only one with obvious bulging), C16/29, C21, and C59/C60.  A number of the component locations use bent leads at a wider spacing than the given size capacitor comes with, so I had to leave C8 and C43 alone for now because the replacements I had available had their leads trimmed too short for this.  For C59/C60 I used one 10mm part with straight leads and one 8mm part with bent leads next to it so they could physically fit the location side-by-side.

  At this point, testing indicates that 5V standby power is present at the purple wire.  This allows the power button to briefly light up if pressed, and the equivalent red LED on the motherboard blips when doing this.  The same condition results if I ground the green power-on wire in an attempt to force the power supply to engage.  When doing this there is a brief burst of voltage on the main 5V and 12V lines and a very tiny audible click from one of the transformers.

  It would appear that the primary power circuitry should work correctly if only the PS would actually latch on when commanded.  I tried an experiment with the PS connected to nothing other than a volt meter where I rapidly and repeatedly grounded the green power-on wire.  The main voltages manage to nearly sustain themselves when doing this, confirming that the primary power output circuitry should function if the control circuit would keep everything latched on continuously.  It's a positive sign (pun intended).  Unfortunately I will have to order more parts and hope for the best when I replace the remaining potential (pun also intended) culprits.

[FdB]

Here’s to positive +signs!

Still trying to clear the decks here so that I may return to my efforts concerning my second, attempted (so far, failed), PSU and order the additional capacitors for several more. I used 12.5mm United Chemi-Con caps to replace the original TEAPO 10mm caps found at C10 and C21. A bit larger, but my personal choice to replace the TEAPOs. Sorry for any concern, but you did warrant an investigation/re-visit here. Thanks.

I still intend to investigate/replace C30, 32 & 45 on my thus-far-failed, second AcBel attempt that seems to perform much like your current project/state.

Have finally opened up a Samsung PSU (from the “Omaha 5”), and quickly closed it right back up after blowing it out. Andy has stated that “about 1 out of 50 of the Samsungs, violently self-destructs for no apparent reason”. Yet another reason for a “no thank you Samsung”. I’ll send Samsungs to Andy. Too jam-packed and otherwise possibly problematic for my taste. AcBels seem much mo’ bettah.

Even the smaller Quicksilver AcBel PSUs are fairly jam-packed (I recently discovered). And, not unlike the still-working MDD 400W AcBel here… this QS PSU also had some swollen and puffed caps… yet it still functions. Only after complete reassembly of the machine did I notice the PSU fan not working!

Fan did seem rather stiff while open/accessible during cleaning, but of course I did not test its function. It “tries” to turn with a little assist “push” through the case and I’d really appreciate specific point-of-oil application insight/methods, just to determine salvageability and IF the fan-circuit functions before simply buying a new fan… only to find that I need to investigate/re-cap the fan control circuitry. I was more focused on the little CPU fan and the processor thermal paste in this 1GHz DP QS, as the heatsink seemed overly HOT with very little run-time demand placed upon it.

Hopefully, a return to these matters in a week or two. Solid congrats on your efforts thus far. Wonder if anyone else here has ventured into their “dormant” PSUs?

[DieHard]

Even the smaller Quicksilver AcBel PSUs are fairly jam-packed (I recently discovered). And, not unlike the still-working MDD 400W AcBel here… this QS PSU also had some swollen and puffed caps… yet it still functions.

Yes, Many of these QS ones with swollen caps work for years, and even when they stop powering on the unit, the old "hair dryer" trick keeps them going even longer.  The "hair dryer trick" can be searched here or googled, I have a unit here that responds to the trick for 6 years...lol and still works...

SEE MORE INFO HERE:

http://macos9lives.com/smforum/index.php/topic,566.msg1500.html#msg1500

[macStuff]

i would so love to have one of those early flat screens in the b+W g3 colors to put with my g3 450
i tried to buy one here locally but it didnt have the stand so i didnt pull the trigger

[Ninester]

Arise old thread..

Posted by: Fury deBongo
« on: December 06, 2017, 09:56:44 AM » Insert Quote
Thanks again DieHard for the splendid info… and muchas gracias to Señor Happy & MacOS Plus.

Plundering Urdvurk’s “MDD silencing thread” here again… geforceg4 & joetramp mention both Everflow and Fractal fans as possible PSU replacement fans. The Fractal fans are interesting…

Reopened PSU to check fan ID. NMB-MATT (Minebea Motor), ball bearing variety… 2410ML-04W-B60. [23.3 cfm, 35dba, 4900rpm, 3.6W. 0.300A]

Mouser (http://www.mouser.com), has a NEW  60x60x25mm “omniCOOL” fan from CUI inc. (CFM-6025V-152-312), rated at 27cfm, 5200rpm, 31.2dba, 1.8W, 0.152A and a 70,000 hour life expectancy… for $6.00 each. So… faster, quieter, move more air, less power consumption AND less expensive. Sounds too good to be true. Check for the larger main fan too?

May order a pair of the small CUI fans… along with the necessary capacitors for the next PSU.

Did the PS fan work out?  I need one

Thanks, Mick

[Ninester]

Found this. Mine is the MAGIC MGA8012HS, no A-20 and .24 vs .27A. Too much current for the fan controller?

https://www.newegg.com/Product/Product.aspx?Item=1YF-003V-003F8

[FdB]

Sorry, away most of day today.

The fans detailed here were for an MDD AcBel PSU.
The MAGIC MGA8012HS is the exact fan used in my QS PSU.

[Ninester]

Reading comp on my part 

I dug in my toy box and found a like fan, 12vdc @ .17A.  Seems to work just fine, slow speeds when cold, much faster when warm. 

I can't say much over stock fan as mine was frozen on delivery last week....

Thx!

[Roman78]

Didn't read the whole thread, but it is possible to mod a normal ATX Power Supply to work in any G4, even the MDD. I Did a ATX-MDD conversion once and posted a how to online, but i can't find it any more. Must be on Macfreak.nl but it's not there, maybe lost by the conversion to the new site.

If someone is interested i could search for the pictures on my NAS.

[IIO]

we had that as topic here someday but the guy who sold the cable harness for ATX to quicksilver has stopped doing so.