portable 2.5 inch USB 2.0 Hard Drive Enclosure error?

[Archman]

howdy,

this is the Windows XP Error Message that windows generates whenever I plug this 2.5 inch USB 2.0 Hard Drive Enclosure into my Dell Inspiron 600m system:

"A USB device has malfunctioned and exceeded the power limits of its hub port. You should dissconect the device"

I am then shown a screen that looks like it is part of the device manager, with usb root hub (6 ports) and it shows 6 items, with one having a question mark. Now, I am not sure what the problem is here... whenever I plug it in, or unplug it and plug it back in I still get this error message.

The device needs no drivers for Win 2000 or XP, and I am using Windows XP Pro. Any ideas as to what is happening??

 

[Peter]

Well you got your answer right there. USB gadget draws more power off the USB port than it's allowed to. With a HDD that's no wonder, since there are NONE that consume less than the 500mA maximum for an USB port - and there's the USB interface inside the enclosure that draws power as well.

Run the thing on its power brick not off the USB power, and it'll work.

 

[Archman]

Well, this thing did not come with an AC adapter, it only has a USB cable and that is it.

 

[akira34]

Did it come with another USB cable that will feed it power (USB on one end, power plug on the other)? If not, then you got a cheap [crap] enclosure... EVERY 2.5" drive enclosure I've ever purchased has always come with a way to give it power on top of the connection cable.

It's not uncommon for laptop USB ports to not provide enough power for the external enclosures. I've seen IBM laptops USB ports not provide enough juice, as well as those dull d600 laptops (we have plenty at work).

 

[Peter]

The official power limit is 500 mA - as I said, even slow-revving, low capacity 2.5" HDD use all of that, and you've got an USB-IDE adapter board to feed as well. So those USB-powered 2.5" HDD enclosures are actually broken by design.

You might have better luck hooking it to a powered hub. Many of those have the power cutoff point well past the 500 mA, while mainboards are usually more cautious.

 

[akira34]

There are 2.5" drive enclosures that can draw enough power throught a desktop/tower USB2 connection to do both power it up and transfer data. Of course, IF you used FireWire (ieee1394a/b) you wouldn't need to worry one lick about not having enough power for the 2.5" drive, enclosure, bridge board and more. Since the full pin count ieee1394 connections have spare wires/connections to provide power to bus powered devices, it's overcome in the spec's. Of course, those tiny [sony designed] (4 pin) ieee1394 connections strip out the power feeds, so you'd be in the same boat again.

Personally, I wouldn't get a 2.5" drive enclosure that didn't have either a FireWire connection on it as well as USB2 or didn't come with a way to give it more power than just the USB2 connection.

 

[Archman]

Okay, here is one thing I may have neglected to mention. The USB cable has two USB connectors, as well as the little end that plugs into the 2.5" enclosure. It almost makes a Y split off of the first USB end, into another very short USB cable with a red coloured plug, while everything else is the same colour... could that be something? Why does it split like that?

thanks

 

[Archman]

okay, silly me... it needed both USB connectors plugged in to work without the issue of drawing too much power.

 

[VirtualLarry]

Originally posted by: Peter
The official power limit is 500 mA - as I said, even slow-revving, low capacity 2.5" HDD use all of that, and you've got an USB-IDE adapter board to feed as well. So those USB-powered 2.5" HDD enclosures are actually broken by design.

You might have better luck hooking it to a powered hub. Many of those have the power cutoff point well past the 500 mA, while mainboards are usually more cautious.

I wonder when some mobo mfgs will start implementing 12V USB on their boards. Since HDs (well, desktop HDs, at least) commonly use +12V for their spindle motors, that would seem like perhaps a wise thing to do, in terms of being able to support USB-connected HDs without any additional power bricks. I'm not sure what the max current spec is for +12V USB, I assume that it's quite a bit higher than normal USB is.

 

[Peter]

USB is 5V, period. If you want that changed, please apply to the standardizing committee at www.usb.org.