Cooler Master RS-350-PSAR-13 dead

[everell]

Here is a sharp looking (but dead) Cooler Master 350 watt power supply. I took some pictures of it before disassembly and repair. Most interesting is a new PWM chip I have never seen.....the chip of the year 2012. Once out of the case and a power cord soldered to the 110 volt input, I powered it up.....and....to my surprise it was working just fine. Voltages were 3.33, 5.09, 12.53, and 5vsb 5.08. Couldn't ask for any better. I put some loading resistors on it, and it still works fine. So what was wrong????? Here are some pictures.

[everell]

Re: Cooler Master RS-350-PSAR-13 dead

This power supply looks just like an Allied SL-8320BTX I have. The Allied has chip of the year 2005. Perhaps same chip but different date of manufacture??? Sure looks the same to me. What you think???

[rogfanther]

Re: Cooler Master RS-350-PSAR-13 dead

I would bet it is the same psu. Even with those radioactive green caps from Anodia...

[everell]

Re: Cooler Master RS-350-PSAR-13 dead

The Cooler Master has a much sharper looking case and a larger fan. Besides, the cooler master is rated for 350 watts.....the Allied is only rated for 300 watts. If only truth in advertising................

[rogfanther]

Re: Cooler Master RS-350-PSAR-13 dead

I have seen some of those Allied failed around here, all seemed to have died because the fan failed then the regulator coil overheated taking the caps with it...

[kolithawick]

Re: Cooler Master RS-350-PSAR-13 dead

I have a cooler master psu as in the pics
it has problem in standby supply.when removed from the pc, standby supply is ok and can be switch on the main supply by short circuiting the (ps on) pin to the ground.(can load the power supply also)
when connected to the pc standby supply trips.(no voltage at the pin)
It looks like a faulty over current trip.
can some body tell me what are the aria to check?

[kolithawick]

Re: Cooler Master RS-350-PSAR-13 dead

please somebody help me....

[Agent24]

Re: Cooler Master RS-350-PSAR-13 dead

Don't know, can you post photos showing the 5vSB circuit? Could be bad capacitors on the 5vSB too.

You haven't actually got a short in your PC on that rail, have you?

[Dan81]

Re: Cooler Master RS-350-PSAR-13 dead

Hmm...

That looks like a pretty beefy Deer/Allied (as you pointed out by the way) and really looks worth a recap. Heatsinks look thick enough and provide some good airflow.

As long as that output torroid is up to par, this one might actually put out 350W.
I wouldn't trust the ANODIA caps on the secondary though.

What connectors does it have?

[kolithawick]

Re: Cooler Master RS-350-PSAR-13 dead

Don't know, can you post photos showing the 5vSB circuit? Could be bad capacitors on the 5vSB too.

You haven't actually got a short in your PC on that rail, have you?

it is exactly same as the one in the picture of post one.
I don't have the circuit diagram.so I couldn't isolate the standby supply.
pc works with another power supply so there can't be short in rail.
if somebody can direct me to find the components which detect the current of the standby supply.( I think it is a faulty cap or faulty resistor in that area.)

[Agent24]

Re: Cooler Master RS-350-PSAR-13 dead

It will help if you can post photos of yours, so we know what condition etc yours is in (There may be some obvious damage you have missed, etc). Someone else's pictures aren't very helpful in that regard, and these ones don't show me what we want to know anyway.

You're going to have to post some photos showing the circuitry because the photos already posted are not up close enough.

In the first I have circled what is probably the 5vSB switching IC, 3-pin device, probably a TOP2xx something at a guess. Also circled the 5vSB transformer.

The second photo shows the general area of where the 5vSB feedback components etc are likely to be located. I can't tell you anything more without more detailed photos of that area, AND a clear photo of the underside of the PCB so we can trace out where the parts connect to.

[kolithawick]

Re: Cooler Master RS-350-PSAR-13 dead

Thank you very much Agent24 for your posts. I have checked blindly the components in the area you marked and found nothing suspected.Again thank you very much taking your time for helping me. I think no point trying to repair this if we can't find the circuit diagram. Thak you very much again.

[Agent24]

Re: Cooler Master RS-350-PSAR-13 dead

Post a photo of the underside of the board so we can find out which parts are actually in the 5vSB circuit... checking random parts blindly won't help if you don't know which circuit they're in.

You shouldn't need a schematic for this, 5vSB circuits are usually very simple, but we do need to identify the actual components.

At least, tell us what number the 5vSB chip is. Like I said, it's probably that 3-leg part I circled on the primary heatsink. Then we can find the datasheet for it, and get a better idea of what to look for or test.

[momaka]

Re: Cooler Master RS-350-PSAR-13 dead

The Cooler Master has a much sharper looking case and a larger fan. Besides, the cooler master is rated for 350 watts.....the Allied is only rated for 300 watts. If only truth in advertising................

Both are overrated, though not that badly. The Cooler Master unit might actually do about 300 Watts continuous and the Allied 200 Watts... but at those loads, the output ripple is almost certainly going to be out of spec. Given the output filtering, I would say these units will do about 200 Watts and 150 Watts clean each, respectively. With better (bigger) output caps, maybe a bit higher. But pushing these units further certainly isn't a good idea.

Another thing worth mentioning: these Allied / Deer / L&C / Solytech PSUs have big dummy load resistor on the output that like to cook the caps. I suggest to anyone fixing such a unit to remove these resistors completely. The 5V rail could do with a 47 Ohm (>1W) or 100 Ohm (>0.5W) resistor if the PSU is going to be used with a 12V-based PC (i.e. just about every computer that has come out in the last 15-17 years).