the gutless, bloated, and fried power supply hall of shame - Page 49

**Behemot** · 02-19-2014, 03:05 AM

Usually ppl just stick something in, for the good feeling you can scope it if it is not oscillating.

**Th3_uN1Qu3** · 02-19-2014, 04:51 AM

The pi filter coils have too low inductance to play a part in the feedback loop.

**Behemot** · 02-19-2014, 04:59 AM

They can have too high for example for -12 V, I sucesfully brought one PoS to oscillation by sticking some inductor instead of wire…changed it for resistor-size inductor than.

**PeteS in CA** · 02-19-2014, 07:12 PM

Yeah, with those wimpy input rectifers, heatsinks, input lytics and main transformer, 250W might be optimistic. But for 200W should be OK. Since you'll be changing them anyway, upping the input lytics to 470uF or even 680uF would be good. And if you can find some 4A or 5A axial standard recovery rectifiers that would fit, replacing those would be good. Do both changes and 250W might be credible.

nasuga · 03-06-2014, 07:04 PM

A couple of weeks ago I've had a cheap powersupply die on me. I can't remember the model but it was a codegen and it came included with codegens 4063 case and was rated for 500W. I left my computer running one night (I tend to leave it running) and when I came back it was dead. I thought maybe a capacitor had blown but I was wrong. What it looks like is that the transformer melted and burnt inside the powersupply. Nobody heard anything when the computer died. The underside of the board was black from the intense heat. I should of taken more pictures and written down the details but it was before I found out about this board and after I've thrown it out. I guess I missed the power supply with the compressor last time I cleaned

. I'm glad there was a soldered fuse or else it would of taken my motherboard and possibly my videocard.

**Agent24** · 03-06-2014, 07:10 PM

If nothing else was burnt, then maybe that choke shorted by itself or there was some power line disturbance which blew it. Seems odd

nasuga · 03-06-2014, 07:18 PM

Quote:

Originally Posted by Agent24

If nothing else was burnt, then maybe that choke shorted by itself or there was some power line disturbance which blew it. Seems odd

Agreed. My brother (who studied as an electrical engineer) told me that it's possible that the varnish or coating on the windings dried/melted and it started shorting. I don't think there was a power line disturbance because I was home at the time and I didn't notice any problems with other electronics or with the lights. Also, the power supply was plugged into a surge protector.

**c_hegge** · 03-06-2014, 09:43 PM

Looks like the input filtering coil. That's very unusual. I've never seen an input filtering coil burn up like that.

**goontron** · 03-06-2014, 10:02 PM

Quote:

Originally Posted by c_hegge

Looks like the input filtering coil. That's very unusual. I've never seen an input filtering coil burn up like that.

looks underrated to me....

nasuga · 03-06-2014, 10:31 PM

I replaced it with a brand new Corsair RM550. Rumor is that they used CapXon caps inside but with a flash light I was able to spot a large chemicon but I couldn't identify the rest. I'm just glad there was a fuse that protected my motherboard even though it's riddled with KT and WX caps.

**c_hegge** · 03-06-2014, 10:45 PM

^
The large PFC cap in those is indeed a Chemi-Con. But the rest of them will be capxon, and will probably fail within 3 years.

**Agent24** · 03-06-2014, 10:47 PM

Quote:

Originally Posted by nasuga

I replaced it with a brand new Corsair RM550. Rumor is that they used CapXon caps inside but with a flash light I was able to spot a large chemicon but I couldn't identify the rest.

Going by this: http://www.pcper.com/reviews/Cases-a.../Detailed-Look it should have UCC KY which are good. (Can see one there anyway, not sure what is buried under the wiring though)

Wouldn't be surprised if some use\used CapXon though, I saw a Corsair CX400, it was full of Su'scon and OST, which are pretty mediocre.

nasuga · 03-06-2014, 10:54 PM

The PSU has a 5 year warranty if it fails. I figured it outweighed the fact that it was built with bad caps. Chances are though that it will fail right after the warranty expires now come to think of it.

**momaka** · 03-12-2014, 04:09 PM

Quote:

Originally Posted by c_hegge

Looks like the input filtering coil. That's very unusual.

Yes.

This is one reason I don't like to see input filtering of ANY kind BEFORE the fuse (except maybe large PPFC chokes). If your breaker doesn't trip, you could be in big trouble.

**Behemot** · 03-13-2014, 01:54 AM

If no breaker trips (there should be at least two of them - the main one and than special ones for phases or even outlets/ligths etc.), why are yo ucertain fuse will burn? There are always slow fuses for high currents, like 5+ A for PSU which wil never draw more than 2 A.

**ben7** · 03-15-2014, 06:27 AM

A possible cause for the filter coil to burn like that is, of course, a shorted turn or two.
Another is, the power supply could have gone unstable and caused excessive high frequency ripple on the primary side, which could burn out the choke (which filters out the high frequency, preventing it from going back into the mains wiring).

**Agent24** · 03-15-2014, 02:54 PM

Quote:

Originally Posted by ben7

Another is, the power supply could have gone unstable and caused excessive high frequency ripple on the primary side, which could burn out the choke

Interesting, haven't heard of that one before. What causes that?

**momaka** · 03-21-2014, 02:51 PM

^Me neither. I think the primary transistors should fail way before that happens, though. Would be an interesting experiment to try to see what it takes to cook one of those input chokes, though (besides too much current). More specifically, how much RF/noise would be needed.

**goodpsusearch** · 05-11-2014, 04:45 PM

Quote:

Originally Posted by momaka

^Me neither. I think the primary transistors should fail way before that happens, though. Would be an interesting experiment to try to see what it takes to cook one of those input chokes, though (besides too much current). More specifically, how much RF/noise would be needed.

http://translate.google.com/translat...l-350-W/1885/1

nice fireworks btw:
http://www.clubedohardware.com.br/ar...l-350-W/1885/8

**momaka** · 05-16-2014, 10:13 AM

^Very interesting. I wish they (clubedohardware) would have done a deconstruction of the coil to see why it burned... i.e. too thin of a wire, improper wire, or what exactly. Would also have been cool to bypass the PPFC and filtering and try to run the PSU again to see how far it would go. The heatsinks look decent. I bet it could hit 300W of raw power (that is, ripple probably won't be in spec on output).

So I guess the conclusion is that now we can't trust input filtering coils in cheap PSUs either.

02-19-2014, 03:05 AM	#961
Behemot Badcaps Veteran Join Date: Dec 2009 City & State: Prague, 50°4'52.22"N, 14°23'30.45"E My Country: CZ Line Voltage: 230 V/50 Hz I'm a: Knowledge Seeker Posts: 4,774	Re: the gutless, bloated, and fried power supply hall of shame Usually ppl just stick something in, for the good feeling you can scope it if it is not oscillating. __________________ Less jewellery, more gold into electrotech industry! Half of the computer problems is caused by bad contacts Exclusive caps, meters and more! Hardware Insights - power supply reviews and more!

02-19-2014, 04:59 AM	#963
Behemot Badcaps Veteran Join Date: Dec 2009 City & State: Prague, 50°4'52.22"N, 14°23'30.45"E My Country: CZ Line Voltage: 230 V/50 Hz I'm a: Knowledge Seeker Posts: 4,774	Re: the gutless, bloated, and fried power supply hall of shame They can have too high for example for -12 V, I sucesfully brought one PoS to oscillation by sticking some inductor instead of wire…changed it for resistor-size inductor than.

02-19-2014, 07:12 PM	#964
PeteS in CA Badcaps Veteran Join Date: Aug 2005 City & State: San Jose, CA My Country: USA, Unsure of Planet Line Voltage: 120VAC, 60Hz & 115VAC, 400Hz I'm a: Professional Tech Posts: 3,504	Re: the gutless, bloated, and fried power supply hall of shame Yeah, with those wimpy input rectifers, heatsinks, input lytics and main transformer, 250W might be optimistic. But for 200W should be OK. Since you'll be changing them anyway, upping the input lytics to 470uF or even 680uF would be good. And if you can find some 4A or 5A axial standard recovery rectifiers that would fit, replacing those would be good. Do both changes and 250W might be credible. __________________ PeteS in CA Power Supplies should be boring: No loud noises, no bright flashes, and no bad smells. ************************** To kill personal responsibility, initiative or success, punish it by taxing it. To encourage irresponsibility, improvidence, dependence and failure, reward it by subsidizing it. ************************** Anti-Covid-Vaxxer pig crap claim/prediction, Doctor: Heart Failure from mRNA Jabs "Will Kill Most People" \| Principia Scientific Intl. ; Dr. Geert Vanden Bossche Warns COVID-19 Jab Injuries and Deaths Will Soon "Collapse Our Health System" (VIDEO) ; Fully Vaxxed May 2021; Since that time I've done 13 5Ks, 1 8K, 12 10Ks, and 4 half marathons

03-06-2014, 07:10 PM	#966
Agent24 I see dead caps Join Date: Oct 2007 City & State: Hiding inside a plated-through hole My Country: New Zealand Line Voltage: 230VAC 50Hz I'm a: Hobbyist Tech Posts: 4,700	Re: the gutless, bloated, and fried power supply hall of shame If nothing else was burnt, then maybe that choke shorted by itself or there was some power line disturbance which blew it. Seems odd __________________ "Tantalum for the brave, Solid Aluminium for the wise, Wet Electrolytic for the adventurous" -David VanHorn

03-06-2014, 09:43 PM	#968
c_hegge Badcaps Veteran Join Date: Sep 2009 City & State: North Coast, NSW My Country: Australia Line Voltage: 240V 50Hz I'm a: Professional Tech Posts: 5,051	Re: the gutless, bloated, and fried power supply hall of shame Looks like the input filtering coil. That's very unusual. I've never seen an input filtering coil burn up like that. __________________ I love putting bad caps and flat batteries in fire and watching them explode!! No wonder it doesn't work! You installed the jumper wires backwards Main PC: Core i7 3770K 3.5GHz, Gigabyte GA-Z77M-D3H-MVP, 8GB Kingston HyperX DDR3 1600, 240GB Intel 335 Series SSD, 750GB WD HDD, Sony Optiarc DVD RW, Palit nVidia GTX660 Ti, CoolerMaster N200 Case, Delta DPS-600MB 600W PSU, Hauppauge TV Tuner, Windows 7 Home Premium Office PC: HP ProLiant ML150 G3, 2x Xeon E5335 2GHz, 4GB DDR2 RAM, 120GB Intel 530 SSD, 2x 250GB HDD, 2x 450GB 15K SAS HDD in RAID 1, 1x 2TB HDD, nVidia 8400GS, Delta DPS-650BB 650W PSU, Windows 7 Pro

03-06-2014, 10:31 PM	#970
nasuga New Member Join Date: Mar 2014 City & State: Ontario My Country: Canada Line Voltage: 120VAC 60Hz I'm a: Knowledge Seeker Posts: 5	Re: the gutless, bloated, and fried power supply hall of shame I replaced it with a brand new Corsair RM550. Rumor is that they used CapXon caps inside but with a flash light I was able to spot a large chemicon but I couldn't identify the rest. I'm just glad there was a fuse that protected my motherboard even though it's riddled with KT and WX caps.

03-06-2014, 10:45 PM	#971
c_hegge Badcaps Veteran Join Date: Sep 2009 City & State: North Coast, NSW My Country: Australia Line Voltage: 240V 50Hz I'm a: Professional Tech Posts: 5,051	Re: the gutless, bloated, and fried power supply hall of shame ^ The large PFC cap in those is indeed a Chemi-Con. But the rest of them will be capxon, and will probably fail within 3 years.

03-06-2014, 10:54 PM	#973
nasuga New Member Join Date: Mar 2014 City & State: Ontario My Country: Canada Line Voltage: 120VAC 60Hz I'm a: Knowledge Seeker Posts: 5	Re: the gutless, bloated, and fried power supply hall of shame The PSU has a 5 year warranty if it fails. I figured it outweighed the fact that it was built with bad caps. Chances are though that it will fail right after the warranty expires now come to think of it.

03-13-2014, 01:54 AM	#975
Behemot Badcaps Veteran Join Date: Dec 2009 City & State: Prague, 50°4'52.22"N, 14°23'30.45"E My Country: CZ Line Voltage: 230 V/50 Hz I'm a: Knowledge Seeker Posts: 4,774	Re: the gutless, bloated, and fried power supply hall of shame If no breaker trips (there should be at least two of them - the main one and than special ones for phases or even outlets/ligths etc.), why are yo ucertain fuse will burn? There are always slow fuses for high currents, like 5+ A for PSU which wil never draw more than 2 A.

03-15-2014, 06:27 AM	#976
ben7 Capaholic Join Date: Jan 2011 City & State: Trenton, NJ My Country: USA Line Voltage: 240/120V 60Hz I'm a: Hardcore Geek Posts: 3,989	Re: the gutless, bloated, and fried power supply hall of shame A possible cause for the filter coil to burn like that is, of course, a shorted turn or two. Another is, the power supply could have gone unstable and caused excessive high frequency ripple on the primary side, which could burn out the choke (which filters out the high frequency, preventing it from going back into the mains wiring). __________________ Muh-soggy-knee

03-21-2014, 02:51 PM	#978
momaka master hoarder Join Date: May 2008 City & State: VA (NoVA) My Country: U.S.A. Line Voltage: 120 VAC, 60 Hz I'm a: Hobbyist Tech Posts: 11,242	Re: the gutless, bloated, and fried power supply hall of shame ^Me neither. I think the primary transistors should fail way before that happens, though. Would be an interesting experiment to try to see what it takes to cook one of those input chokes, though (besides too much current). More specifically, how much RF/noise would be needed.

05-16-2014, 10:13 AM	#980
momaka master hoarder Join Date: May 2008 City & State: VA (NoVA) My Country: U.S.A. Line Voltage: 120 VAC, 60 Hz I'm a: Hobbyist Tech Posts: 11,242	Re: the gutless, bloated, and fried power supply hall of shame ^Very interesting. I wish they (clubedohardware) would have done a deconstruction of the coil to see why it burned... i.e. too thin of a wire, improper wire, or what exactly. Would also have been cool to bypass the PPFC and filtering and try to run the PSU again to see how far it would go. The heatsinks look decent. I bet it could hit 300W of raw power (that is, ripple probably won't be in spec on output). So I guess the conclusion is that now we can't trust input filtering coils in cheap PSUs either.