Ultra ULT-LS6000P 600W ATX

[bsweasel]

I have this Ultra ULT-LS6000P 600W ATX, blown primary input caps, and a Resistor that sits between them that I can't read the colors. Anyone have a schematic on this or have one they can ID the R3 resistor? Pictures show caps removed, the glue between the circles is the location for R3. And you can see the resistor sitting on the table next to it. Any help would be appreciated!

Regards.

[mariushm]

Re: Ultra ULT-LS6000P 600W ATX

Can't you measure the resistance with a multimeter? It's possible the resistor's still good, just burnt a bit.

Going at it logically, as you have capacitors C6 and C7, the R2 and R3 should be just like them... R3 should be the same as the R2... and they're probably bleeder resistors (to drain the capacitors when the psu is turned off). But I can't say 100% it's the same as R2.

[b700029]

Re: Ultra ULT-LS6000P 600W ATX

I doubt it can do 600W... looks like 400-450W at most.

You can trace the circuit near the resistor to figure out what it's connected to. That should help you guess its value from the purpose. It might be a bleeder resistor for the primary caps.

[bsweasel]

Re: Ultra ULT-LS6000P 600W ATX

Well, I guess this is how I learn, your suggestions are right on. the resistance on R3 is 100k ohms as it R2. and they are crossing traces between the primary caps. I assumed because it was toasted on the outside that it was shot, but it appears to be ok. I'm going to drop it back in with some new caps and see if it powers up.

[everell]

Re: Ultra ULT-LS6000P 600W ATX

The burn damage to the resistor might actually be the glue dried and went conductive and started burning. Before reinstalling the main capacitors, scrape all that old dried glue off the pc board. You may have had a conductive path between the two big capacitors because of that glue. This problem shows up on lots of power supplies.

Also scrape any of that old glue off the capacitors.

[Th3_uN1Qu3]

Re: Ultra ULT-LS6000P 600W ATX

Those resistors are anywhere between 100k and 200k. They have two purposes. First, since the big caps are in series, they equalize the voltages across the two caps. Second, they discharge them in a reasonable amount of time (a couple minutes at most) after the plug is pulled, so you can safely work inside the PSU. Their exact value isn't critical - just that both need to be the same.

[370forlife]

Re: Ultra ULT-LS6000P 600W ATX

RSY built Ultra unit, I wouldn't trust it for much over 400W.

[bsweasel]

Re: Ultra ULT-LS6000P 600W ATX

Well, this PS is teaching me a lot....since I replaced the caps and verified those resistors. I've found a trace on the back side that is "missing a chunk", a completely burnt resistor under the heatsink that holding a bad NPN Transistor. Apparently when the fan goes, this thing went strait to burns ville. I've already found what I think to be a good replacement for the burnt Resistor, but I'm not sure about this NPN Transistor. Found a datasheet on it, but I'm not versed enough to know where to get a replacement. Can anyone suggest where to get a KSH13009H transister?

[ratdude747]

Re: Ultra ULT-LS6000P 600W ATX

That's defiently NOT a 600W by design... Ultra did make a 600W in their Xfinity series that (after 5VSB mods and a recap) was a actually a 600W. Also watch out for thin wire- Ultra likes to do that on 12V plugs (p4, PCI-e, etc.)

[bsweasel]

Re: Ultra ULT-LS6000P 600W ATX

That's defiently NOT a 600W by design... Ultra did make a 600W in their Xfinity series that (after 5VSB mods and a recap) was a actually a 600W. Also watch out for thin wire- Ultra likes to do that on 12V plugs (p4, PCI-e, etc.)

So it sounds like Ultra is no different than the rest of the PS manufactures that lie on their labels..... It's irrelevant though, I'm just fixing it to learn and possible have a spare if I get it going.

[c_hegge]

Re: Ultra ULT-LS6000P 600W ATX

Well, this PS is teaching me a lot....since I replaced the caps and verified those resistors. I've found a trace on the back side that is "missing a chunk", a completely burnt resistor under the heatsink that holding a bad NPN Transistor. Apparently when the fan goes, this thing went strait to burns ville. I've already found what I think to be a good replacement for the burnt Resistor, but I'm not sure about this NPN Transistor. Found a datasheet on it, but I'm not versed enough to know where to get a replacement. Can anyone suggest where to get a KSH13009H transister?

That would be one of the switching transistors. http://www.newark.com/on-semiconduct...lar%20Products would probably work as a replacment.

EDIT: replace both switching transistors. They both need to be absoloutely identical to work

[mockingbird]

Re: Ultra ULT-LS6000P 600W ATX

RSY built Ultra unit, I wouldn't trust it for much over 400W.

Thanks for this...

I have an "Ace Power" 400w that seems to be the same OEM... The PCB is not black, but the design is similar enough... Mine is Model ATX-60B and dates from 2011/07/07... I re-capped the thing, still won't turn on at all. Will try to get pics.

[c_hegge]

Re: Ultra ULT-LS6000P 600W ATX

This kind of reminds me of a sun pro. RSY and sun pro do sometimes copy each other's designs. I don't know why, though. If you're gonna copy someone else's design, copy Seasonic or Delta.

[ratdude747]

Re: Ultra ULT-LS6000P 600W ATX

This kind of reminds me of a sun pro. RSY and sun pro do sometimes copy each other's designs. I don't know why, though. If you're gonna copy someone else's design, copy Seasonic or Delta.

Why? If you are so cheap as to copy an old design, why would you copy such an expensive to build design. Their customers don't know or care about quality, so why not maximize profits?

[370forlife]

Re: Ultra ULT-LS6000P 600W ATX

This kind of reminds me of a sun pro. RSY and sun pro do sometimes copy each other's designs. I don't know why, though. If you're gonna copy someone else's design, copy Seasonic or Delta.

Usually one company will make a design and either sell it to another that dosen't have a strong engineering background, or they simply copy eachother. They are going to copy a low cost design otherwise they still wind up with a expensive product that ruins their competitive edge. Also, just because they copy eachother dosen't mean they will perform the same. Case and point, KKpower and leadman, KKpower designed a decent performing single transistor forward unit with a DM311 for the 5vsb that could do all the way up to 650W in ATX spec, leadman copied the design and made a huge mess of it, and it couldn't do anything past 300W without getting all funky and ripply with the waveforms.

Though that has happened where a cheap companies copies a nice design from a good company, LongYi copied the Delta built Antec earthwatts 650W unit and sold it as a Coolmax 950W, but the LongYi unit had a hard time with anything over 450W.

[mockingbird]

Re: Ultra ULT-LS6000P 600W ATX

Notice the "YC" on his transformers... On mine they say Yong Cheng.

[Rulycat]

Re: Ultra ULT-LS6000P 600W ATX

Perhaps they copy eath other's designs because they don't have a big enough engineering group to design every model, so they sell each other different series...

[RJARRRPCGP]

Re: Ultra ULT-LS6000P 600W ATX

At least it don't have the dreaded 4-diode setup.

(Classic of bottom-of-the-barrel PSUs)

[lti]

Re: Ultra ULT-LS6000P 600W ATX

The board was designed for four diodes.

[bsweasel]

Re: Ultra ULT-LS6000P 600W ATX

This thing is driving me crazy.... I'm starting to question if its worth fixing. So these resistors are around the switching transistors on primary side. Hoping someone can confirm my color translations:
Brown:green:black:gold:brown
Black:green:black:silver:brown
Hard to tell, they have both been heated, so the colors look dull to me....or maybe I'm getting color blind. Really wish I had a schematic of this pile.