USB Enclosure power bricks not all the same?

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_Korruption_

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So, I've got a Vantec Nexstar 3.5" USB 2.0 HDD enclosure. My friend has the Bytecc ME-740U2 3.5" USB 2.0 HDD enclosure. Both have physically similar power bricks, the +12V lead and the +5V lead are both in the same position in the keyed power connection.

He was without his power brick, and he thought that my power brick should work on his enclosure without a problem. So we plugged everything in and flipped the switch. Nothing. The LED on the enclosure was flashing, like it was struggling to stay on. Same applied for the LED on my power brick, it was struggling to stay on. The brick works on my drive and enclosure without a problem.

So we think nothing of it, and just put his drive aside for the time being. But then we started to smell the burnt PCB... and we knew we were in trouble. The controller board on his 120GB Seagate 7200.7 was burnt, and the smell was permeating the air.

The only difference in my power brick is that it is rated to deliver up to 2.0A on the +12V and 2.0A on the +5V. Going off memory, his will output 1.5A on the +12V line. As far as I know, that is irrelevant, because the drive only draws a fraction of that amperage.

Anybody have any ideas? His drive is already dead (lost about 120GB of misc. stuff), but I'd just like to get to the bottom as to why it would fry everything.
 
Did you actually check the voltages with a multimeter, or are they just labeled? I guess it could also just be chance...
 
That's odd.

Regardless of how much MORE amperage is available on the 12V or 5V, the power supply should have only delivered power as needed.

Are you CERTAIN the pin out was correct? If the interface was the same and the voltages were correct and the pin-out the same, I would think you'd be fine.
 
I remember it being correct. The two top pins were +12V and +5V, and the two bottom pins were both ground. Here's a picture I just took.

usb_brick.jpg
 
Did you check the shield part? It looks like yours is grounded, his might not be. Or, as said above a "pinout" problem.
 
_Korruption_ said:
The plug itself was physically the same.
Click to expand...

It very well may be the same plug. Your picture shows “RTN” or return, or ground going to the two lower pins and the metal shield part. Some companies ground the shield at one end, some ground it at both ends.
 
Here's some images from him for reference. The pinout was the same.

Pinout.jpg

Brick.jpg


And an image of the PCB on his HD. Circled in red is what blew up.
 
_Korruption_ said:
And an image of the PCB on his HD. Circled in red is what blew up.
Click to expand...

That makes me think the problem with the hard drive doesn't have to do with the power supply. The "issue" made it all of the way through the enclosure's circuitry and then that far into the hard drives? I could be wrong, but that's weird.
 
Both of us have the same drive (120GB Seagate 7200.7 with 8MB), so we're probably going to temporarily swap drive PCBs and get the data off his drive. I really hope that my PCB doesn't get fried either. We're not going to use it in an enclosure again, that's for sure. ;)

You know anything about PCB swaps, jonny?
 
Good luck with the swap. It might not work though, I read somewhere that the newer drives are pretty much mated for life with their PCBs. Something to do with the cluster size and calibration.
 
If it won't work, will the drive just not spin up, or will something fry like last time? Did a rough search in the Disk Storage forum with the keyword "PCB" and came up with several worklogs of people swapping their drive PCBs with success. The date codes on my drive and his drive aren't too far apart.
 
Last time I did a PCB swap on a HDD was to a couple Samsung drives back in '98.

It worked, but that was ages ago... especially in computer years. ;)
 
Will it damage your PCB? More than likely, no.

I'm just saying don't be too disappointed if it doesn't work.
 
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