[dexter1]

I decided to part with my Crimson with PowerSeries skins, so in an attempt to document the working condition of the machine i set up a video to show the system after i was cleaning it up and getting everything ready.

I connected the power cable to the system and turned on the outlet. I did not flip the front switch to "on" yet. The breaker on the back was set to "on" since the handle broke off a long time ago.
Not to my big surprise, the system didn't start initially, but slowly the fans set in gear and the loud humming started.
At this moment i noticed a flickering in the keyboard led and the leds on the Kingston AUI. That's not good.

So i caught this on video and i've uploaded it to my site at: https://tudl1910.home.xs4all.nl/videos/Crimson_on.mp4

This somehow reminds me of the story of CB_HK in https://forums.irixnet.org/thread-427.html

Meh, i don't know what to do. I can perhaps spend some time pulling out the PowerOne PSU and diagnose it on a bench. Chances are that i need a 300V module or a 5V module and i honestly don't want to spend the money on this since it was decided that it should go to another enthusiast to clear a lot of room to do something else with the space.
I've looked on Ebay and those PSU's go for 250 USD and that's without shipping.

And yes, i did flip the switch to the "on" position at a later time only to get Green and orange leds at the PS3 and some distinct acid odor coming from the machine. That's not good either.... The PS3 did show "F" but didn't progress further.
I am a bit stupid, i admit, to do this foolheartedly, and i did power it on some time ago to see it running properly.

So, what should i do? Take out the PSU put it on the table and get some 300V readings?

[CB_HK]

Dexter,

There’s a good chance the PSU has suffered a blown component or two. The only way to know for sure is to pull it out and check it on the bench.

What I will also mention is that I eventually had to replace ALL the capacitors on my Crimson. I had an issue after repairing my PSU where the machine would only run for about 20 minutes and then start spontaneously rebooting. While I never found the specific cap that was causing the issue, I ended up replacing all the backplane caps (as well as any other cap I could find). After doing this the machine has been rock solid.

I don’t say this to be alarmist. Just being realistic that these machines are a bit sensitive to old, dried out caps.

Feel free to DM me if you want to discuss anything specific. I’ll be happy to help however I can!

[jan-jaap]

So, what should i do? Take out the PSU put it on the table and get some 300V readings?

The 300VDC will almost certainly be OK. I've not seen an output module fail either, so far.

A common failure mode of these PSUs seems to be the backplane that ties everything together. There's an aux power supply which powers the control logic and the fan. I've seen things fail in this area.

You're going to have to diagnose the PSU on a bench with a dummy load. Beware that part of the control circuitry isn't galvanically isolated from the mains, you'll need special HV isolated probes for the oscilloscope.

I documented some of my adventures with the PowerOne PSU's here:

https://www.vdheijden-messerli.net/sgist...wersupply/

and

https://www.vdheijden-messerli.net/sgist...-powerone/

but the most reliable way to fix these PSUs is to buy another PowerOne SPM5 chassis and transplant to mainboard. I think I've had to rebuild all of my PowerSeries PSUs by now, at least the PowerOne units are serviceable.

[dexter1]

Thanks CB_HK, i know there is no other way around than to dig through the PowerOne and search for the culprit.

And i have found it:

That board was literally soaked in electrolyte. The brown goo is the stuff i dabbed from the bottom array of electrolytes. It is so bad that the lacquer on the board has loosened. and created pockets where the fluid had accumulated.

This explains the erratic behavior of the machine. Apart from that, the second +12V -12V board looks fine. I haven't checked the 300V on the base module due to time constraints.

Technically this is fixable by desoldering all the caps, put the board in a sonic bath, remove all the loosened lacquer, check all components which can be checked by a multimeter, bridge corroded paths and resolder new caps.

Boy, what a big job this is. If there is a reasonable alternative by acquiring a 5V170A board or maybe a 5V150A board for not too much money, i wouldn't have to do this. Chances are that i have to use 170A because of the Reality Engine.

Can anyone shed some light on the way forward? Is the repair doable?

Note: Thanks Jan-Jaap for the pointers and your affirmation that the 300V is okay. The Crimson wouldn't have come this far without it.

[CB_HK]

Let me check my spare PSU when I get home. I don’t remember if it’s a 170 or 140 amp module. If it’s 170 I may have an easier solution for you.

As for doing the repair yourself: it’s definitely doable. It’s not easy but I had to do a similar amount of work for mine. What you’ve outlined sounds like a good way forward to get it all working again.

[CB_HK]

Unfortunately I don’t have a spare 170 amp module. I’d recommend a rebuild, as you mentioned doing. Hopefully it will be as straightforward as it should be. Swapping out the caps and ensuring nothing else ended up blown and you should be back to running.

Good luck! Let me/us know if you run into any issues.

[Raion]

GODDAMN that's a lot of damage. I don't envy you.

[jan-jaap]

Boy, what a big job this is. If there is a reasonable alternative by acquiring a 5V170A board or maybe a 5V150A board for not too much money, i wouldn't have to do this. Chances are that i have to use 170A because of the Reality Engine.

Can anyone shed some light on the way forward? Is the repair doable?

Sounds like the output caps of the 5V rail bought it. The repair is definitely doable. I wouldn't cheap out wit a 150A module except for testing maybe.

Honestly, unless there's a lot of damage on the component side of the PCB I'd just fix it.

[dexter1]

After a lot of preparation and purchasing stuff i had sufficient tools to desolder the caps on the 5 volt PowerOne output module. I decided to first desolder the caps and then do a proper cleaning.



I used my Weller 40W for this since the solder only melts at higher temperatures
It became clear that the green lacquer has loosened from the copper connecting each steel terminal. That's not a big problem, but i do need to re-mask that part and any other bare copper pads.

After finishing desoldering all the caps, the bottom looks like:



The copperpads have become stained so i might need to polish them when resoldering the caps and covering it with the mask, otherwise corrosion can spread further.

The top part with the shielding, transformer and daughterboard removed looks like this after cleaning:



I cleaned the board with soapy water and a toothbrush, and after rinsing i submerged it in demineralized water and refreshed it twice to get rid of any minerals and contaminations. It's now on a bench drying, which probably will take a week or so.

This is the transformer i pulled from the board:



Along with the daughterboard (not shown) these components were not affected by the electrolyte. A bit of blowing off some soot and dustbunnies was enough. The heat shroud (also not shown) which is bolted onto the transformer only needs some new thermal grease which i have, so that part is covered.

This is the entire lot of caps i pulled from the board. Note the goo on the gold colored caps::



Amazingly, all caps still have the correct or higher capacity when measured!

Replacement shoppinglist for the PowerOne 5V@170A is below. Note that these all are 105C specced caps (sizes are length x diameter x lead spacing) :

9 x yellow Elna cers 9149 105C 10V 1000uF 40mm 12.5mm 5mm
2 x green Nichicon h8904 105C 10V 1000uF 25mm 13mm 5mm
1 x brown Sxg 1 (2) 9R (M) 105C 10V 470uF 12mm 8mm 5mm
1 x blue Nichicon h9135 105C 35V 47uF 12mm 8mm 4mm
2 x blue Nichicon h9143 105C 35V 47uF 12mm 8mm 4mm

I'll be checking out online stores like RS-online and Farnell for the correct replacement caps. Will keep you posted on my progress.

[Irinikus]

WoW, those caps look pretty wasted!