General Power question, can a 10% over-amp fry a drive?

joe7dust

Limp Gawd
Joined
Jan 25, 2013
Messages
137
I ordered a 2A adapter. Didn't pay attention when it arrive, plugged external HD in --- poof smoke. Drive lights up but not detected by OS anymore. I look on the adapter and it says 2.2A... when the drive specifies 2A. I complained to the seller because they listed it as 2A, but they claim this isn't enough difference and it isn't their fault. Hmm....
 
You can't over amp a drive. It pulls what it needs. The PSU could have been putting out dirty power (High Voltage or Ripple) and thats what killed the drive, but not the amperage.
 
Anyway to prove this with a multimeter? I have been offered $10 for the price of the cable but my actual loss was closer to $65 and they aren't budging apparently although I haven't opened an ebay case yet. I'm 95% certain you can't get more than an item's value that way though, and it's not worth suing over so most likely I'm just screwed either way. Thankfully there wasn't any vital data on there or that could have been one expensive piece of Chinese garbage for sure!
 
Last edited:
What voltage is it? Are you sure that was right for the drive? And measure it to see if it's accurate per the rating.
 
once you really grok Ohm's law it all becomes so clear

impedance sets the ratio of potential to kinetic energy in a system
 
The higher amp rating doesn't hurt, but the low quality of the AC adapter could, and I have a feeling it put out too high a voltage. Sometimes that happens only during the first fraction of a second because the adapter wasn't designed right and overshoots a voltage.

Don't buy an AC adapter unless it's safety certified by UL or CSA and has registration numbers from those organizations. The uncertified stuff includes only very basic voltage regulation, no overvoltage protection, and probably no overcurrent protection (unless the latter is inherent in the design).

Here's what Bytecc and Vantec have shipped with their enclosures. There are no components on the underside:

oldbyteccvsnewacadapter.jpg


This is the power supply found inside an enclosure, and it definitely did blow out somebody's hard disk (chip fried, left a 1/4" burn mark in the enclosure):

nonul.jpg



In comparison, here's a UL approved AC adapter with 2 regulator chips on bottom, an AC line filter, and more components in general:

ulapprovedadapter.jpg
 
Last edited:
Back
Top