Is this power supply safe to use?

[Newbie2]

Hello people,

My brother is using a generic "The Best Power" MT-500P 500W power supply to power his computer, which I formerly owned. I did recap it and made a thread about it a year ago (https://www.badcaps.net/forum/showthread.php?t=4267), as a replacement for the L&C power supply I used to have in an Athlon XP computer I formerly owned, but I got its original 200W HIPRO power supply and used that instead of the Best Power PSU.

I'm just wondering if it's safe to use. It's powering a power hungry Prescott P4 system, and here are its specifications:

Intel Pentium 4 3.2GHz Prescott Socket 478 (SL7PN, 1MB L2 cache, HT enabled)
2GB DDR333 RAM (2x1GB)
PCCHIPS M955G motherboard
Sapphire ATI Radeon HD3650 512MB DDR2 AGP 8X video card
120GB WD Caviar SE ATA/100 hard drive
AOpen 16X DVD+/-RW IDE PATA optical drive
Generic "Best Power" MT-500P 500W power supply
Microsoft Windows Vista Home Premium (OEM) SP1 x86
Razotech Transformer black mid-tower case

Here are the "The Best Power" power supply's pictures:





The UL number on the label of this power supply is E199529, and a search of that UL number reveals that E199529 belongs to "CASING MACRON TECHNOLOGY CO LTD", a Taiwanese power supply manufacturer. However, there are no markings of that company anywhere on the silkscreen on the board in the inside of that power supply, instead there are model numbers like "ISO-500" and whatever around the area where the fuse is. I do a Google search for ISO power supplies, and one ISO-500 power supply I find has the UL number of "E161451" (picture here: http://www.atxcases.com/products/upl.../DSC03603.JPG), which belongs to the infamous "CHANNEL WELL TECHNOLOGY CO LTD" power supply manufacturer, known for producing some power supplies for Antec in the past. I'm guessing that this power supply was produced by Channel Well, due to the Fuhjyyu and Teapo capacitors originally in it. Do you guys think Channel Well or Casing Macron manufactured the "The Best Power" 500W power supply my brother has?

To return to my original question, would this power supply be safe to use in my brother's computer?

[zandrax]

Re: Is this power supply safe to use?

Judging from trafo sizes, it resembles more a 200W than a 500 one. I saw missing filter caps and coils: expect a lot of noise ad ripple; moreover, if the psu fails the whole pc may be damaged.
Chosing the most unreliable component between the PcChips motherboard, the psu and Vista, I'd pick the psu: it seems a Powmax relative
In short: better buy a new psu.

Zandrax

[i4004]

Re: Is this power supply safe to use?

not safe.
get him fortron(if you're on the budget) or corsair(if you have bit more money).

i would use this only for ocassional test or backup purposes, if that.

not having filtering stage is something one could forgive(as that big cap can soak mains variations etc.) but having +5Vstby of such a crappy design is unforgivable.
and i dunno if even a best cap there can take the beating...

ie that is the sort of psu that kills mobos.

[kc8adu]

Re: Is this power supply safe to use?

its a gutless wonder.
missing lots of parts.
funny orange fan though.makes it hard to tell if its normal or on fire!

[Wizard]

Re: Is this power supply safe to use?

My same thoughts, is it on fire!?

It's a eeeeh!! power supply, get one of these others have recommanded.

Cheers, Wizard

[Newbie2]

Re: Is this power supply safe to use?

funny orange fan though.makes it hard to tell if its normal or on fire!

The LED fan is actually red, my camera made it look orange. I put it in there myself, just for fun. It actually helps make my brother's computer "cool" (that's what he says) because his case has a side window and along with a blue LED exhaust case fan he thinks it looks cool.

I have an old Antec SL450 450W power supply which was manufactured by Channel Well, but it has lots of Fuhjyyu caps inside.

[Oklahoma Wolf]

Re: Is this power supply safe to use?

ISO is Channel Well's bargain brand. But I'm not sure this is one of those - Macron, which has no connection to CWT, sounds a little more like it.

The reason I say this, is you can usually tell a CWT made unit by the transformer markings. There should be one or more with the "CWT" initials there, or the UL file number for CWT. Those aren't present here.

Of course, if it really is an ISO, it could very well be those markings wouldn't be there anyway...

[Newbie2]

Re: Is this power supply safe to use?

ISO is Channel Well's bargain brand. But I'm not sure this is one of those - Macron, which has no connection to CWT, sounds a little more like it.

The reason I say this, is you can usually tell a CWT made unit by the transformer markings. There should be one or more with the "CWT" initials there, or the UL file number for CWT. Those aren't present here.

Of course, if it really is an ISO, it could very well be those markings wouldn't be there anyway...

I do believe it is an ISO power supply manufactured by Channel Well and not a Macron-made power supply, because around the fuse section it lists ISO power supply models (ISO-300, ISO-500, etc.) to use which rating of fuse for. There were Fuhjyyu capacitors originally in this "The Best Power" power supply before I recapped it. There is another power supply with the Best Power name and MT-500P model number, it is different from this one because it has two gold fan grills, 24-pin ATX connector, and the holes on the back of that different Best Power PSU are in a different arrangement (I know because I seen it at a local computer store about a year ago). That other Best Power PSU could have been manufactured by Macron, while this one was manufactured by Channel Well and they used the same label between the two with the Macron's UL number.

Also, the ISO power supply in that picture I linked in the first post of this thread (the Norwood Micro PSU) looks identical to this "The Best Power" power supply, without the second fan. Below is a comparsion of the ISO-500 and "The Best Power" MT-500P power supply:

Norwood Micro ISO-500 power supply:


"The Best Power" MT-500P power supply:


The Best Power PSU my brother has is doing the job of powering his computer fine with stable voltages, although in the future I am thinking to convincing my brother to replace his "cool" power supply with my old Antec SL450 power supply.

[Newbie2]

Re: Is this power supply safe to use?

Bump...

[Newbie2]

Re: Is this power supply safe to use?

Bump...

[PCBONEZ]

Re: Is this power supply safe to use?

No not OK on Prescott.

No input filter.
Gutless wonder. (Maybe 250-300 watts)

May be okay on an old P3.

[kc8adu]

Re: Is this power supply safe to use?

for the amount of damage a cheap assed psu can cause to the computer and your home i stay away from junk.
do what you are comfortable with.
i would toss it.
or crush it for exercise.

[zandrax]

Re: Is this power supply safe to use?

Don't try it: it's average Deer production, even unreliable for old pcs.

i would toss it.
or crush it for exercise.

Hitting it with a hammer is enough?

Zandrax

[kc8adu]

Re: Is this power supply safe to use?

more fun to wad it up like a beercan.

[Newbie2]

Re: Is this power supply safe to use?

Okay, looking back at willawake's 420W ISO power supply it appears that the Best Power 500W power supply is a heavily stripped-down version of willawake's ISO 420W power supply.

Best Power 500W:



ISO 420W (willawake's power supply):


If you look carefully, you'll see that the Best Power 500W power supply has the same basic PCB layout, so that proves that my brother's Best Power 500W power supply was manufactured by Channel Well Technology.

I still haven't been able to convince my brother to change his power supply though.

[i4004]

Re: Is this power supply safe to use?

it seems to me your convincing-foo is weak.
hit him over the head with it...

[gdement]

Re: Is this power supply safe to use?

Ask him how he feels about his hard drive.

In the past I had 3 consecutive drive failures with identical symptoms (stretched out over a year or so). I finally realized there was a pattern and wised up about the cheap PSU I had been using. I can't prove the connection, but the failure mode of those drives hasn't recurred ever since.

[i4004]

Re: Is this power supply safe to use?

what were those drives(manufacturer), and what symptoms did you experience?

[zandrax]

Re: Is this power supply safe to use?

If you look carefully, you'll see that the Best Power 500W power supply has the same basic PCB layout, so that proves that my brother's Best Power 500W power supply was manufactured by Channel Well Technology.

Hmm, not so sure: Willa's one has a sticker on the main transformer containing the CWT acronim, the BP hasn't. Are there some CWT reference on BP's pcb?

I still haven't been able to convince my brother to change his power supply though.

Isn't the lack of RFI filters enough? Try powering an hair dryer in the same wall plug your brother's pc is connected and powered on: I expect some weird symtomps, e.g. dizzy screen, lockups or BSODs ...

Zandrax

[i4004]

Re: Is this power supply safe to use?

mhm..why do you think hair dryer would affect so much?

most rfi it does are in spectrum that disturbs antenna reception because of sparks etc., i think.
ie i didn't saw problems when i had cheap psu...

any small problems that could occur on mains will be soaked up by mains cap that's behind the rectifier...

rfi filters probably mostly protects mains from psu itself, than protecting psu from mains...heh...

from
Practical Switching Power Supply Design - M. Brown (1990) WW.pdf

"3.1 The EM1 Filter
This section is composed of a small L-C filter between the input line
and the regulator. It serves a dual purpose. First, C, and L, act as a
high frequency radio-frequency interference (RFI) filter, which reduces
the conducted high frequency noise components leaving the switching
suppty back into the input line. These noise currents would then radiate
from the input power lines as in an antenna. The lowpass cutoff frequency
of this filter should be no higher than 2 to 3 times the supply's
operating frequency. The second purpose of this stage is to add a small
impedance (L,) between the input line and the bulk input capacitor. It
basically reduces any lethal transient voltage and allows the bulk input
filter capacitor and any surge protector to absorb the destructive energies
from the input line spikes or surges with little chance of exceeding any
of the components' voltage ratings."

and these lethal transients are so rare that even these cra ppsu rarely die of them.
they die because low quality components...
ie one spike that last few us won't destroy bulk cap.
you don't see these exploding or being damaged very often...