[CB_HK]

Hey all,

If you've seen my past posts regarding my Crimson you'll know that I had to rebuild my PSU in order to solve some big power issues (random restarts, turning off, etc.).

Unfortunately some issues have cropped up again and I'm seeking advice from the community about where I might find my gremlin this time.

The current issue is manifesting as occasional un-commanded restarts in addition to the machine just simply turning off. Not in a nice way, either. Just straight to off. The PSU fan continues to run and the power switch is still set to ON.

Based on when these issues crop up--anywhere from 60 to 90 minutes after power on--I'm inclined to believe that my gremlin may reside in either the temperature sensor or the circuitry on the PS3. I know the single tower series were sensitive to environmental conditions and I'm wondering if there might be a failing component with the monitoring system.

To add to the mystery, every electrolytic cap inside the machine has been replaced. In the PSU, on the PS3, on the backplane, and each VME.

Does anyone with single tower experience have any thoughts what this issue might be?

[Raion]

I don't unfortunately have any ideas but I would greatly appreciate if you and Dexter1 would eventually go through and make some rebuild guides on the power supply components here. If you have a list of what you used and general guides on how to do it than that might make things easier for those who follow your footsteps.

[jan-jaap]

If the overtemp protection triggers (justified or not), a red thingie to the left of the power switch on the front (PS3) panel should pop out.

You're supposed to let it cool down, push back the red thingie, and live happily ever after.

I'm guessing that's not what's happening.

My own crimson is currently down with similar symptoms, except it happens much sooner -- usually before the system is fully booted.

IIRC I swapped the PSU with my 4D/440, confirmed the problem went away and put 'rebuild Crimson PSU' on my TODO list -- unfortunately this hasn't happened yet. My Crimson is my last 4D which needs to have it's PSU redone.

My procedure isn't very sophisticated, but it works. So far all the real problems in my PowerOne PSU's have been in the backplane, the board where all the output modules plug into. Either the aux inverter which powers the control logic, or the control logic itself. I've tried blind capacitor swaps and it never did much. Fortunately, the PowerOne SPM5 series come in many configurations, but they all share the same backplane. So I just hit eBay for a "Power One SPM5", any configuration, cheap. If you look at the long enough you'll be able to roughly estimate it's age from the style of the label and the serial #. Choose a young one -- they made them until 2005 or so. You can also get an HPM5 but then it'll only work on 220VAC and you'll have to swap out the rectifier section too. Be sure to set the jumper bank on the new backplane like the old one or it can get weird.

NB: I spent a lot of time trying to figure this thing out. I reversed part of the schematics, bought isolated probes for my scope, ... In the end time is finite, and this worked for me.

[GanjaTron]

Based on when these issues crop up--anywhere from 60 to 90 minutes after power on--I'm inclined to believe that my gremlin may reside in either the temperature sensor or the circuitry on the PS3.

Have you checked for over/undervoltage conditions on the PS3? Be careful not to short any of those pins when probing -- easy to do. Otherwise I'd suspect the inhibit signal is going flaky -- most likely in the PSU then.

JJ, didn't you once mention something about the optocouplers in the PSU going bad?

--GT

[CB_HK]

jan-jaap, that's what I was afraid of. I don't understand why I've been having such bad luck with these PSU backplanes. I suppose we can argue age and that may very well be it. I know the board tested well before I installed it per our conversations last year when I was first troubleshooting this problem.

Off to eBay to find another donor!

Raion, I'll attempt to document the process and create a guide for folks as I go this time. Since it will be a post, Dexter and jan-jaap can chime in with their inputs as well. Might be worth a sticky if we pull it off well!

GanjaTron, I've checked the PS3 and haven't seen any voltage issues at this point. I'll keep an eye on it though just in case there's intermittent flashing I haven't seen.

Thanks all!