Maxpower PL-400 bad voltages

[Ant3G]

I got PC on repair with this bad PSU (Maxpower PL-400, 400w) which was overheating (vent blocked by alot dust).
Unfortunately, PSU fryed MBO and CPU because of huge oscilation in voltages.
5v oscilating for +-2v, and 12v oscilating between 6-10v.

When I opened it, 3 caps were bad (2200mF). When i swapped them, nothing changed.

Is there anything I can check and swap component for low cost or should just throw it away?

Thanks in advance

[kc8adu]

Re: Maxpower PL-400 bad voltages

without a pic its hard to say.if its the one i am thinking of the standard test is to drop it in the trashcan.if it makes a clunk when it hits the bottom its bad.

[Scenic]

Re: Maxpower PL-400 bad voltages

couple threads on those Rexpower/Maxpower PL-4xx on here

https://www.badcaps.net/forum/showpo...&postcount=166
https://www.badcaps.net/forum/showpo...&postcount=110
https://www.badcaps.net/forum/showth...light=maxpower

probably the same thing under yet another name (as mentioned in the thread linked above)
https://www.badcaps.net/forum/showthread.php?t=9446

[c_hegge]

Re: Maxpower PL-400 bad voltages

You could re build it like I did with mine, but if you don't want to do that, then the garbage bin is really the best place for it

[Ant3G]

Re: Maxpower PL-400 bad voltages

Will post pics tomorrow, but anyway psu is going into garbage in 2-3days.
Dont have time, neither parts to rebuild it.

[Ant3G]

Re: Maxpower PL-400 bad voltages

Here are pics so maybe someone can learn or find something from them. PSU is going into garbage. I dont have all the parts to rebuild it.
Thanks for help to all of you who posted!

[goodpsusearch]

Re: Maxpower PL-400 bad voltages

That power supply is not bad. I would recap it and put a full input filter and keep it.

I believe that the reason of the voltage flunctuation is bad main caps. I have seen those HECs fail a lot in maxpower psus.

[Evil Lurker]

Re: Maxpower PL-400 bad voltages

When a psu gets to the point where it eats a motherboard, basically IMO its not safe until you can test out the voltage sensing circuitry of the houskeeping IC. If a zener or other component has gone it cannot properly tell the PWM controller whats going on the secondary side. That could result in the PWM switching on too long or the duty cycle gets increased too much your looking at more blown caps or dead motherboards. Or if it is detecting too much voltage the reverse happens and the PWM tries to correct by reducing the duty cycle.

IMO its not worth rebuilding since I don't see very many yellow 12v wires running off of it... its basically your typical older atx revision that is more heavily proportioned towards 5v output. You would probably be better off getting a new cheap unit with at least 20+ amps on one or more 12v rails with hopefully good sensing circuitry and build it up.

But at the same time that PSU is not worth throwing away either. You can always salvage the fan off of it, and the housing makes for excellent project boxes. I took one here a while back, did some drilling on top of it mounted a cheap harbor freight 6 outlet wall plate adapter on top and it is now a power strip.

[c_hegge]

Re: Maxpower PL-400 bad voltages

It actually looks a bit better in some ways, but worse in other ways than my Rexpower-branded version. It does actually have an ERL-35 transformer (mine just had a 33), but that PSU would be illegal to run here in Aus, since there is no input filtering. One other problem is that Jamicon caps are junk and should NEVER under any circumstances be used, especially for re-capping.

[Ant3G]

Re: Maxpower PL-400 bad voltages

One other problem is that Jamicon caps are junk and should NEVER under any circumstances be used, especially for re-capping.

Store at my place dont have better caps (next time will need to ebay caps). Will buy new cheap PSU.

That power supply is not bad. I would recap it and put a full input filter and keep it.

Was afraid of that. None of the stores dont have them at my place. Even if they have it would be crap :P
Nothing without ebay and waiting for few days/weeks.

Thanks for suggestions

[retiredcaps]

Re: Maxpower PL-400 bad voltages

Nothing without ebay and waiting for few days/weeks.

If you live in the USA, you have choices like badcaps.net, mouser.com, and digikey.com. USA members here get their digikey.com order in 48 hours.

[c_hegge]

Re: Maxpower PL-400 bad voltages

Carefull with using fleabay for caps. 90% of sellers only sell fake caps (ie. caps with rubycon on the label which are really made by HongKongFlyApart company (R), LLC). I'd recommend Badcaps.net. His prices are great, his caps are genuine, and he ships worldwide (almost).