OCZ technology OCZ500SXS PS

[sandrabrnelic]

Hi !

I'm new here on forum and i hope i can learn something about PS repair from experienced people here.

My problem is PS from title. It's OCZ but inside is FSP group FSP500-60GLY(NEW2) board. The problem is that 12V and 5V outputs are to low when PS is under load. 5V is low (4.6V) even without load. I have changed all caps at 5V and 12V outputs but problem is still there. I have checked shottkey diodes at output and they are all ok. What should i check next ?

[999999999]

Re: OCZ technology OCZ500SXS PS

Has it always been like this? I mean is it new and arrived like this or did it work previously, and is it possible it worked previously meaning it powered a system but was always too low on 5V & 12V rails?

Might just be a pot contact or misadjustment issue.

There is a potentiometer inside in front of the transoformer, yes? It has a little orange adjustment screw, use a fine tipped marker to mark the screw and body of the pot to indicate what it's initial dial position was, then turn it back and forth several times with power OFF. Next with it on by jumpering the connector green PS_On signal to a black ground wire, turn the pot slightly one way and/or the other while reading the voltages.

I suggest doing this without it connected to a computer to make sure all rails (not just 5V and 12V, but especially also 3.3V) are within spec before hooking it up to the computer again to do load testing to more finely tune the adjustment of the pot.

Ideally you would use an insulated screwdriver since there's live mains + high DC voltage present. Be careful.

[sandrabrnelic]

Re: OCZ technology OCZ500SXS PS

It was working previously, but it started to make problems. PC began to have problems and started to reset itself in the middle of work without obvious reason. And later it had problems even to start. After i have realised it's PS problem i have changed PS but since i have some experience in electronics i have decided to learn something about power supplyes ... so i'm here now.

Regarding a potentiometer contact i think it is ok because i forgot to mention that PS outputs are not stable (they oscillate +/- 0,3V). I have tried to move pot and it can rise 5V voltage to 5V but only when i turn it full to the end but voltages are not stable. Problem must be somewhere else. I will look at outputs with scope later (when i get it) so maybe this will help ...

Thank you for your efforts, and forgive me for my crappy english.

[tom66]

Re: OCZ technology OCZ500SXS PS

Your English is better than my Croatian!

What brands of capacitor are used in the power supply?

[sandrabrnelic]

Re: OCZ technology OCZ500SXS PS

Capxon

[tom66]

Re: OCZ technology OCZ500SXS PS

Capxon

That could be your problem, do any feel like they are not flat (bulging) when you touch them?

[c_hegge]

Re: OCZ technology OCZ500SXS PS

^
he said he already replaced them (at least for the rails in question).

[tom66]

Re: OCZ technology OCZ500SXS PS

^
he said he already replaced them (at least for the rails in question).

Hmm, did he replace good caps with CapXon, or CapXon with good caps?

[PeteS in CA]

Re: OCZ technology OCZ500SXS PS

What frequency are the O/Ps "oscillating" at? If at 100Hz, then the I/P caps are a likely cause.

[sandrabrnelic]

Re: OCZ technology OCZ500SXS PS

.... 4 months later ....

Thank you Pete, it was just like you said

In the meantime i have built C/ESR meter which helps me a lot to detect dead caps ...

I have found dead Taepo on primary side (100uF/25V). Changed it and my OCZ is again working like new one.

[Rulycat]

Re: OCZ technology OCZ500SXS PS

You wouldn't mind sharing how you built the ESR meter, would you?

[ben7]

Re: OCZ technology OCZ500SXS PS

You wouldn't mind sharing how you built the ESR meter, would you?

Theres a few circuits on the web, namely this one.

[ben7]

Re: OCZ technology OCZ500SXS PS

bumb ubm!

Wut?