Hard Drive Power Supplies

[goontron]

Re: Hard Drive Power Supplies

ok, mine developed an issue. it pulses on switch one then eventually starts. Thats a startup cap issue right?

[kaboom]

Re: Hard Drive Power Supplies

Severe RFI from one of these turds:
http://www.eham.net/articles/34513

As soon as I saw them on ebay and newegg a few years ago, it was obvious they'd be causing trouble.
The missing filter sections, on the line side, are important.

So in addition to shock hazards from carbon tracking/untrimmed leads and no EGC bonding to the secondary common, they also function as "RFI generators," disguised as power supplies...

Or, cow pies, disguised as power supplies.

FWIW, a few days ago, I crushed a Raidmax under my foot- output leads all labeled #20AWG, but probably were ~#21AWG. +3.3 had no magamp and shared the common inductor with +/- 5/12. No pi-sections on the outputs. Ceramic y caps instead of proper ones, missing line-side filter sections. AC rectifiers were two 4005s and two of something between those, and 2A05s. Bigger than a 400x, but not quite a 2A device.

And, by the way, it also needed caps. To coin a phrase, "Jee Saturn, Fuhjyi-yoo!"

That junk was gone. It'll never have the potential (!) to stress (kill?) another system... At least it was now "ultra-small form factor."

[goontron]

Re: Hard Drive Power Supplies

Just a heads up, there have been HDDs spotted in the wild that require 3.3V.

So the ideal HDD adapter would have 12v, 5v, and 3.3v, and two connectors, one SATA power, one molex.

sigh, i will rig something up.

[mockingbird]

Re: Hard Drive Power Supplies

Just a heads up, there have been HDDs spotted in the wild that require 3.3V.

So the ideal HDD adapter would have 12v, 5v, and 3.3v, and two connectors, one SATA power, one molex.

[goontron]

Re: Hard Drive Power Supplies

Betcha won't do that again...






5.5A on +5, maybe...

ahh, better for running laptop drives!

[kaboom]

Re: Hard Drive Power Supplies

well, since the thread was dug up...
This is the Unit i use now to power drives externally. It came out of a well built HP tape drive.

Notice the proper isolation and air-gaps, duely optocouplers, thick secondary traces, and good filtering all around.

It doesn't disconnect the primary to shut off, it just kills the primary switchers, so that heatsink on the primary switcher is always live. (i learned that the hard way)

Betcha won't do that again...

No brown gorilla snot here! Only issue i have with it is crap caps, but its not enclosed and doesnt run hot, so im not too worried..... HP drove the tape motor from 5V, can you tell?

5.5A on +5, maybe...

[goontron]

Re: Hard Drive Power Supplies

well, since the thread was dug up...
This is the Unit i use now to power drives externally. It came out of a well built HP tape drive.

Notice the proper isolation and air-gaps, duely optocouplers, thick secondary traces, and good filtering all around. It doesn't disconnect the primary to shut off, it just kills the primary switchers, so that heatsink on the primary switcher is always live. (i learned that the hard way) No brown gorilla snot here! Only issue i have with it is crap caps, but its not enclosed and doesnt run hot, so im not too worried..... HP drove the tape motor from 5V, can you tell?

[kaboom]

Re: Hard Drive Power Supplies

mine developed a primary to secondary short and zapped the living shit out of me today. found carbon traces on the underside of the board.

Interesting. This confirms there is no secondary-to-EGC bonding. Which means when they fault while connected to the computer, the USB cable does fault duty. If the EGC were connected to the secondary common, [i]as it is in every by-code power supply," all that would've happened is either the carbon traces burn clear, or the fuse blows. And that assumes the fuse in in the hot wire.

Who wants to guess that the induced voltages on the USB pair don't kill the host controller?


I actually borrowed one of those SATA/IDE->USB things after I couldn't use the SD card reader on a semi-trashed shitsta system. Someone working at the same place also does networking. I told him about those power supplies, but all I got was "It's fine for backups."

I go back there this weekend and will have to print this thread and leave it. It confirms my suspicions that the "three-wire" AC cord is only for "show."

They're as bad as the fake apple chargers as far as shock hazard...

[mockingbird]

Re: Hard Drive Power Supplies

Sorry to bump an old thread, but I came across another variant of the Yu Feng, and it is almost completely identical to it except that this one has a brown PCB and all Capxon caps (KM and KF).

The soldering of the underside of this one is a lot cleaner, and this one has "23-11056-00 REV. A" written on it.

The datecodes on the caps indicate this was made in the beginning of 2005.

[budm]

Re: Hard Drive Power Supplies

Meanwell spec

[mariushm]

Re: Hard Drive Power Supplies

Can't really compare a TDK power supply with a Meanwell. Yeah, meanwell will work, but with a lousy efficiency and potentially high ripple on outputs.

If you go that route, you could just as well pick the 14$ special on newegg, a shitty logisys : http://www.newegg.com/Product/Produc...16&ignorebbr=1

[budm]

Re: Hard Drive Power Supplies

jameco.com:
http://www.jameco.com/webapp/wcs/sto...0001_323505_-1

http://www.jameco.com/webapp/wcs/sto...0001_323425_-1

http://www.jameco.com/webapp/wcs/sto...0001_323362_-1

[mariushm]

Re: Hard Drive Power Supplies

You can get one of these : http://www.digikey.com/product-detai...891-ND/2057040

and add a dc-dc converter to get 5v out of 12v, something like this : http://www.digikey.com/product-detai...6-5-ND/2259781

Just move everything into another case, so you won't have mains connectors exposed and you're done.

... or you know, just get a decent transformer like this one : http://www.digikey.com/product-detai...1075-ND/242519 , two bridge rectifiers (or 8 diodes), four capacitors and two linear regulators and you're in business.

[lti]

Re: Hard Drive Power Supplies

Maybe I should make my own power supply. I don't have a computer I can use for cloning or copying files from drives. Cloning a 500GB drive over USB 2.0 will take a while.

I have a DVD recorder power supply with switched 5V and 12V outputs for the PC DVD burner it used. I don't know how much ripple the outputs have, but it will handle 2A on both outputs without blowing up if I put a heat sink on the 12V regulator and point a fan at it.

[goontron]

Re: Hard Drive Power Supplies

mine developed a primary to secondary short and zapped the living shit out of me today. found carbon traces on the underside of the board.

[999999999]

Re: Hard Drive Power Supplies

I wouldn't consider the one on the right a quality product.

The capacitors are practically glued to the to220 rectifiers, the heatsink is barely adequate, transistor/mosfet on the primary side is screwed in the corner of the metal sheet, as if the heat will spread all the way to the other side efficiently . Both have that horrible pcb that has copper on only one side, all through hole. They could have put the bridge rectifier on the heatsink with the transistor/mosfet on the primary side, flip the common mode chock 90 degrees, put the capacitor vertically, and voila.. plenty of space available.

There is no need to heatsink a rectifier handling less than 1/10th of an amp. Similarly with the rest of the design, all it has to do is supply a couple amps peak output at HDD spin-up, with the cheap caps being the likely early failure point.

It might even be overbuilt for the application except that the size of the transformer limits it. Consider it may average 7W output, then contrast a consumer grade PSU capable of 500W output. Is the latter built with 70X more heatsinking and current capability? In the transformer yes but not the rest.

[mockingbird]

Re: Hard Drive Power Supplies

I wouldn't consider the one on the right a quality product
...
Both have that horrible pcb that has copper on only one side, all through hole.

I suppose I should have posted a pic of the underside of the Yu Feng as well. That SOIC in the top right corner is a Chinese branded 3843A.

The capacitors are practically glued to the to220 rectifiers<snip>

This is meant to power a single HDD at a time, strictly for retrieving data, a task that would take an hour at the most. If I were doing a ghost, I would open up the case and attach the HDD to the PSU because I need native access. There's no reason to base a suppy for such a simple task on a 'doctorate design'. This is more than adequate for its intended use.

[goontron]

Re: Hard Drive Power Supplies

I was looking at one of those. It's good to know that the power supply sucks.

I have wanted one of those adapters for a long time. There are USB 3.0 adapters now, but they cost so much more that I don't want to get one and have to buy a separate power supply. Most of the USB 3.0 adapters include a 12V-only power supply, so they probably get 5V from the USB port.

other than that the adapters are good. you can even issue commands like idle-unload and standby-immediate and they will reach the drive. it doesn't say it supports linux, but even linux 2.2 (as far as i've tested it) supports its chipset.

[lti]

Re: Hard Drive Power Supplies

Sigh.. you can get a VIPER50A for less than 2$ in quantity and put it on a trip of metal on one side and configure it to do 12v 3A or something like that.
Put the schottky diode and a 5.2v (to account for voltage loss on cable) 2A dc-dc converter on the other side on a long strip of metal. Done.

That would be nice. I would even take one that doesn't use the IC if they output 12V and use some kind of regulator for 5V.

im going to pick up one of these soon. it comes with a 2amp nameplate even though its more like 300ma with ripple is spec. i will see how far i can load it. i will record the whole thing too.

I was looking at one of those. It's good to know that the power supply sucks.

I have wanted one of those adapters for a long time. There are USB 3.0 adapters now, but they cost so much more that I don't want to get one and have to buy a separate power supply. Most of the USB 3.0 adapters include a 12V-only power supply, so they probably get 5V from the USB port.

[goontron]

Re: Hard Drive Power Supplies

im going to pick up one of these soon. it comes with a 2amp nameplate even though its more like 300ma with ripple is spec. i will see how far i can load it. i will record the whole thing too.