Poer surge on Hub Port

[Guest GKW in GA]

I recently purchased a portable external hard drive. It's a USB powered

drive. When I plug it into my laptop and try to copy something to it, I get a

dialogue box that says "Power Surge On Hub Port, A USB device has

malfunctioned and exceeded the power limits of it's hub port. You should

disconnect the device"

 

What causes this? I don't think there is anything wrong with the drive

because this is the 2nd one of these that I have had this happen with. I

though about switching to a portable external hard drive by another

manufacturer

[Guest db.·.. >]

Re: Poer surge on Hub Port

 

personally i would

review the homesite

for that device.

 

but maybe there is

something here as

well:

 

http://search.microsoft.com/results.aspx?mkt=en-US&setlang=en-US&q=Power+Surge+On+Hub+Port

 

--

 

db·´¯`·...¸><)))º>

 

 

"GKW in GA" <GKWinGA@discussions.microsoft.com> wrote in message

news:3FDAD8F7-69BB-4A40-A5E8-5F05D7AF3CC8@microsoft.com...

>I recently purchased a portable external hard drive. It's a USB powered

> drive. When I plug it into my laptop and try to copy something to it, I get a

> dialogue box that says "Power Surge On Hub Port, A USB device has

> malfunctioned and exceeded the power limits of it's hub port. You should

> disconnect the device"

>

> What causes this? I don't think there is anything wrong with the drive

> because this is the 2nd one of these that I have had this happen with. I

> though about switching to a portable external hard drive by another

> manufacturer

[Guest Malke]

Re: Poer surge on Hub Port

 

GKW in GA wrote:

> I recently purchased a portable external hard drive. It's a USB powered

> drive. When I plug it into my laptop and try to copy something to it, I

> get a dialogue box that says "Power Surge On Hub Port, A USB device has

> malfunctioned and exceeded the power limits of it's hub port. You should

> disconnect the device"

>

> What causes this? I don't think there is anything wrong with the drive

> because this is the 2nd one of these that I have had this happen with. I

> though about switching to a portable external hard drive by another

> manufacturer

 

If by "USB powered" you mean that the external drive doesn't have its own

power connection and is getting power from your computer (which is how I

interpret your post), your computer doesn't provide enough power for this.

You should stop using this device with that particular computer immediately

as there is a good chance of permanently damaging your motherboard.

 

Malke

--

MS-MVP

Elephant Boy Computers - Don't Panic!

FAQ - http://www.elephantboycomputers.com/#FAQ

[Guest Paul]

Re: Poer surge on Hub Port

 

GKW in GA wrote:

> I recently purchased a portable external hard drive. It's a USB powered

> drive. When I plug it into my laptop and try to copy something to it, I get a

> dialogue box that says "Power Surge On Hub Port, A USB device has

> malfunctioned and exceeded the power limits of it's hub port. You should

> disconnect the device"

>

> What causes this? I don't think there is anything wrong with the drive

> because this is the 2nd one of these that I have had this happen with. I

> though about switching to a portable external hard drive by another

> manufacturer

 

There is a solution for this, but it isn't a very satisfying one.

(By that I mean, it probably works most of the time, but I

wouldn't want to power something that needs a whole 1 ampere of

current with it.)

 

http://secure.serverlab.net/shop/graphics/00000001/yCable.jpg

 

That cable has two connectors on one end of the cable. One connector only

uses the power pins, while the second is a full USB connector.

The two connectors go into the computer USB jacks. The connector

on the right, is a small square USB one, that would plug into

the hard drive enclosure. (If the enclosure doesn't have a

removable USB cable, then this won't work.)

 

(computer (small square end

end) Plugs to the drive)

 

+5V -----------------------+---- +5V

Data+ ------------> Data+ |

Data- ------------> Data- |

GND ---------+----- GND |

| |

| |

GND ---------+ |

(none) |

(none) |

+5V -----------------------+

 

The basic idea, is the power output of two USB ports is combined.

 

A single USB port, has a limitation of 5V @ 500mA. That is a total

of 2.5W. Some 2.5" hard drives, when they're spinning at their

normal speed, need less power than that. But the 10 second interval,

where the drive starts from zero RPM, and the platter spins up, that

takes more energy. On some drives, it might take double the power,

for the first ten seconds. (On, say, a 7200RPM 2.5" hard drive.)

 

Inside the laptop, there are a couple options for power handling.

The lazy way, is to use a simple Polyfuse, and use a single fuse to

protect two USB connectors in one stack.

 

USB1 ---+------ Polyfuse ----- +5V inside laptop

USB2 ---+ 1.1 amps

 

Now, if that is the way they did it, then you likely wouldn't

have had a problem at all.

 

There is another way to do it, involving "precision policeman"

chips. These monitor current consumption on each port, and cut

off the port if more than 500mA is drawn.

 

USB1 -------- current_monitor ------- +5V inside laptop

USB2 -------- current_monitor ------- +5V inside laptop

 

If you were to get one of those "two headed" or "USB Y cables",

then one small issue, is the electricity doesn't know which

of the two cable heads to flow down. It is possible for the

cables to "current hog", and one connector might still draw

the majority of power. I don't know how the cable designer

can ascertain that all customers will be satisfied by the

usage of the cable. There isn't enough voltage drop budget

in the USB standard, to go sticking resistance in the path,

to even up the current flow and get closer to an even split

on each cable. There are some active power methods (i.e.

placing a switching regulator in the circuit), that could guarantee

a fix, but that would cost money. As far as I know, the cable

scheme above is a "dumb" one, without circuits inside the cable.

 

The external hard drive may have provision for a separate adapter input

(barrel connector input on the shell of the enclosure). If so,

you could purchase the optional adapter, and plug that into

the drive. That means you have to be near an A.C. power source,

when you want to use the external USB drive.

 

If you purchase one of those USB Y-cable things, then it should

do the job, and still allow a portable solution. As long as the

drive is not drawing more power than such a crude solution

can provide, without tripping the laptop "current surge"

detection.

 

Example of a cable for sale here.

 

http://www.amazon.com/Cables-Go-Y-Cable-mini-USB/dp/B0013LQD7Y/ref=pd_bbs_sr_1?ie=UTF8&s=electronics&qid=1216527014&sr=8-1

 

HTH,

Paul

[Guest Patrick Keenan]

Re: Poer surge on Hub Port

 

"GKW in GA" <GKWinGA@discussions.microsoft.com> wrote in message

news:3FDAD8F7-69BB-4A40-A5E8-5F05D7AF3CC8@microsoft.com...

>I recently purchased a portable external hard drive. It's a USB powered

> drive. When I plug it into my laptop and try to copy something to it, I

> get a

> dialogue box that says "Power Surge On Hub Port, A USB device has

> malfunctioned and exceeded the power limits of it's hub port. You should

> disconnect the device"

>

> What causes this?

 

An excess current draw by the attached device.

 

Look at the specs for the ports and the attached devices. The answer is

clear.

> I don't think there is anything wrong with the drive

> because this is the 2nd one of these that I have had this happen with. I

> though about switching to a portable external hard drive by another

> manufacturer

 

Hard disks typically draw around an amp. A USB port provides, at most,

*half of that*.

 

This is why external drive cases come with their own power supplies, or in

the case of laptop drive cases, with a 3-headed cable. You must attach two

of the heads to two *separately powered* USB ports - one for power only, and

one for data and power - before attaching the drive.

 

And those two ports must be separately powered, by which I mean they cannot

be on one multi-hub attached to *and powered by* one port on the PC. If

you're using an external powered USB hub, you must be sure that the hub's

power supply exceeds the attached current draw - this means more than an

amp.

 

Otherwise, the message you receive is entirely expected and as designed.

 

HTH

-pk

[Guest Patrick Keenan]

Re: Poer surge on Hub Port

 

"Paul" <nospam@needed.com> wrote in message

news:g5ue6s$j4u$1@registered.motzarella.org...

> GKW in GA wrote:

>> I recently purchased a portable external hard drive. It's a USB powered

>> drive. When I plug it into my laptop and try to copy something to it, I

>> get a dialogue box that says "Power Surge On Hub Port, A USB device has

>> malfunctioned and exceeded the power limits of it's hub port. You should

>> disconnect the device"

>>

>> What causes this? I don't think there is anything wrong with the drive

>> because this is the 2nd one of these that I have had this happen with. I

>> though about switching to a portable external hard drive by another

>> manufacturer

>

> There is a solution for this, but it isn't a very satisfying one.

> (By that I mean, it probably works most of the time, but I

> wouldn't want to power something that needs a whole 1 ampere of

> current with it.)

 

If you look at the label on a typical hard disk, that's the rated current

draw.

 

 

> http://secure.serverlab.net/shop/graphics/00000001/yCable.jpg

>

> That cable has two connectors on one end of the cable. One connector only

> uses the power pins, while the second is a full USB connector.

 

These cables are very commonly provided with USB cases for laptop drives.

They work very well, as long as you attach them to separately powered ports.

I use them all the time.

 

These cases usually have a power adapter jack - but don't come with the

adapter, and they can be hard to find. The cables work well, unless the

cables themselves are crap. I've had one fit that descripton.

 

fullsize drives in cases should be used with the supplied power adapters.

 

-pk

 

 

<snippage>