Re: Power Surge On Hub Port

From: w_tom (w_tom1_at_hotmail.com)
Date: 08/23/04 

Date: Sun, 22 Aug 2004 20:53:04 -0400

  Each USB port controls and limits power provided to the
peripheral. There is no surge. The peripheral device tried
to draw more power than the USB port (hub port) permits. How
much power is permitted? This is requested by USB peripheral
software and provided by the computer USB controller (hub
port).

  The answer to your question is found in why is the
peripheral draws too much power? Windows software programming
error? USB controller programming error? Problem with the
USB port current monitoring hardware? Obtain further
information and testing to answer this question.

  In the meantime there is a major difference between a surge
and a peripheral drawing too much power. If you don't
appreciate the difference, then finding the solution can
become more difficult.

Ramiah wrote:
> I am trying to use a 2.5 hard drive in a 2.0 USB enclosure, with
> an IBM Think Pad 2.0 PCMCIA card, in an IBM T20 running XP
> Professional. The problem is, when I plug the external drive into
> the PCMCIA card I receive this error message: "A USB device has
> exceeded the power limits of it's hub port. For assistance in
> solving this problem, click this message". WhenI click the
> message there are 2 choices, reset or cancel. I follow the
> directions to reset the drive, but my question is why do I get
> this power surge? Why is there incompatibility with using this
> 2.5 drive as a back up device? Any assitance is greatly
> apreciated, thank you in advance.

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