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  #1  
Old January 24th 19, 06:53 AM posted to alt.comp.os.windows-10
lonelydad
external usenet poster
 
Posts: 90
Default I need help!

I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File Explorer
will show the two partitions, but won't open them. Is there some utility I
can use to rebuild the file tables or whatever so I can access the data?
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  #2  
Old January 24th 19, 07:12 AM posted to alt.comp.os.windows-10
Paul in Houston TX[_2_]
external usenet poster
 
Posts: 999
Default I need help!

lonelydad wrote:
I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File Explorer
will show the two partitions, but won't open them. Is there some utility I
can use to rebuild the file tables or whatever so I can access the data?


It is an encrypted Passbook?
  #3  
Old January 24th 19, 10:21 AM posted to alt.comp.os.windows-10
Paul[_32_]
external usenet poster
 
Posts: 11,873
Default I need help!

lonelydad wrote:
I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File Explorer
will show the two partitions, but won't open them. Is there some utility I
can use to rebuild the file tables or whatever so I can access the data?


In Disk Management, check to see if the disk is offline.

https://www.eightforums.com/data/att...89a87f7614.jpg

( https://www.eightforums.com/threads/...-online.53106/ )

If you make "exact" clones with a tool like "dd" or "ddrescue",
then the second drive will go offline automatically, and will
refuse to go online when you try and switch it.

If you take a drive which has no special situations pending,
the online/offline is discretionary. For example, if a disk
won't "Safely Remove" due to NTFS TXF transaction feature
being used by backup software, setting the drive manually
to "Offline" is your first step. Followed by using "Safety Remove",
then powering off the drive and unplugging.

When you set a drive to "offline", the machine remembers for
the next time, so you have to visit Disk Management yet again,
and put it "online" again.

*******

You can gain access via

1) Testdisk, "list files", "copy files". But the interface
is clunky and there is a learning curve. It will "get around"
a number of issues.

2) Macrium Reflect backup of the disk to a .mrimg file. If you cannot
arrange that to happen, then there is more than an "administrator
permissions" type problem.

You can "mount" backed-up partitions stored inside .mrimg files
using the right-click context menu. There is a tick box to
"allow access to restricted stuff" in the interface, and this
should allow access to a partition with some sort of tricky
permissions.

However, if the backup won't run, that's a hint this isn't
all that simple of a problem.

It could be encryption, and there are many different encryption
schemes. Encryption at the drive level, might not even show
partitions before it is unlocked.

WDC makes My Book (3.5") and Passport (2.5") external drives.
There could be others. A Passport external could be a 9.5mm
high drive. But both WDC and Seagate have dabbled in 15mm tall 2.5"
drives (they don't fit in a laptop bay), which hold up to 5TB.
And presumably those have their own trade name.

The nasty part about some of the externals now, is they're no
longer SATA drives inside, and the drive only has a USB connector
right on the controller. And this limits data recovery options
a bit. I wouldn't buy one of those! Just the thought of the
resulting hair loss, is enough to keep me away from them.

Paul
  #4  
Old January 24th 19, 07:02 PM posted to alt.comp.os.windows-10
lonelydad
external usenet poster
 
Posts: 90
Default I need help!

Paul in Houston TX wrote in
:

lonelydad wrote:
I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File
Explorer will show the two partitions, but won't open them. Is there
some utility I can use to rebuild the file tables or whatever so I
can access the data?


It is an encrypted Passbook?


no

  #5  
Old January 24th 19, 10:28 PM posted to alt.comp.os.windows-10
Keith Nuttle
external usenet poster
 
Posts: 1,844
Default I need help!

On 1/24/2019 1:02 PM, lonelydad wrote:
Paul in Houston TX wrote in
:

lonelydad wrote:
I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File
Explorer will show the two partitions, but won't open them. Is there
some utility I can use to rebuild the file tables or whatever so I
can access the data?


It is an encrypted Passbook?


no

Dumb question: Was this drive the main drive in another computer, and
could the inaccessible partitions be system partitions when it was
the main drive with the OS on it?

If there is no data on the drive you could reformat in in make it one
large partition.

You may check the Disk Management (Right click the Windows Icon on the
left end of the tool bar and see what it says about the questionable
partitions)

I believe there is software to attach Drive letters to those partition,
so File explorer can see them.



--
2018: The year we learn to play the great game of Euchre
  #6  
Old January 25th 19, 02:04 AM posted to alt.comp.os.windows-10
lonelydad
external usenet poster
 
Posts: 90
Default I need help!

Keith Nuttle wrote in news:q2dall$1dar$1
@gioia.aioe.org:

On 1/24/2019 1:02 PM, lonelydad wrote:
Paul in Houston TX wrote in
:

lonelydad wrote:
I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File
Explorer will show the two partitions, but won't open them. Is

there
some utility I can use to rebuild the file tables or whatever so I
can access the data?

It is an encrypted Passbook?


no

Dumb question: Was this drive the main drive in another computer, and
could the inaccessible partitions be system partitions when it was
the main drive with the OS on it?

If there is no data on the drive you could reformat in in make it one
large partition.

You may check the Disk Management (Right click the Windows Icon on the
left end of the tool bar and see what it says about the questionable
partitions)

I believe there is software to attach Drive letters to those

partition,
so File explorer can see them.



I had two questinable hard drives on my PC. I copied the contents of
those two drives to two partions on this external USB drive. I did not
get a chance to restore the contents to regular hard drives [SATA]
before it started acting up.

Disk Management will sometimes see the device, but the partitions are
undefined. If I put my hand on the box I can feel the heads seeking
constantly. I won't die if I don't get the data back, but there is a lot
of stuff I spent a long time collecting that I will miss and probably
can't recreate.
  #7  
Old January 25th 19, 02:16 AM posted to alt.comp.os.windows-10
Dan Purgert
external usenet poster
 
Posts: 281
Default I need help!

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

lonelydad wrote:
Keith Nuttle wrote in news:q2dall$1dar$1
@gioia.aioe.org:

On 1/24/2019 1:02 PM, lonelydad wrote:
Paul in Houston TX wrote in
:

lonelydad wrote:
I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File
Explorer will show the two partitions, but won't open them. Is

there
some utility I can use to rebuild the file tables or whatever so I
can access the data?

It is an encrypted Passbook?


no

Dumb question: Was this drive the main drive in another computer, and
could the inaccessible partitions be system partitions when it was
the main drive with the OS on it?

If there is no data on the drive you could reformat in in make it one
large partition.

You may check the Disk Management (Right click the Windows Icon on the
left end of the tool bar and see what it says about the questionable
partitions)

I believe there is software to attach Drive letters to those

partition,
so File explorer can see them.



I had two questinable hard drives on my PC. I copied the contents of
those two drives to two partions on this external USB drive. I did not
get a chance to restore the contents to regular hard drives [SATA]
before it started acting up.

Disk Management will sometimes see the device, but the partitions are
undefined. If I put my hand on the box I can feel the heads seeking
constantly. I won't die if I don't get the data back, but there is a lot
of stuff I spent a long time collecting that I will miss and probably
can't recreate.


It's a longshot, and will be markedly harder because it's USB, but toss
it in a freezer bag with some dessicant packets for say overnight. Then
stick that whole package in the freezer before you leave for work.

I've had a few successes with freezing dying harddrives. It doesn't
always work, but sometimes it's just the ticket.

Don't try to recover right from the drive -- use something to as quickly
as possible make an image of the drive, then work off the image (I'm
primarily a Linux guy, so ddrescue comes to mind ... unfortunately, I
don't know of any Win equivalents).

Once you've got the drive image to work from, recover data from that
(depending on the tool, may require a new drive to write the image to --
think burning an ISO to CD/DVD). Lot safer working from an image on a
known-good (or brand new )drive than it is trying to poke around a
dying drive trying to remember where you stuck that paper / music /
whatever.


HTH.

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--
|_|O|_| Registered Linux user #585947
|_|_|O| Github: https://github.com/dpurgert
|O|O|O| PGP: 05CA 9A50 3F2E 1335 4DC5 4AEE 8E11 DDF3 1279 A281
  #8  
Old January 25th 19, 06:12 AM posted to alt.comp.os.windows-10
T
external usenet poster
 
Posts: 4,600
Default I need help!

On 1/24/19 1:21 AM, Paul wrote:

The nasty part about some of the externals now, is they're no
longer SATA drives inside, and the drive only has a USB connector
right on the controller. And this limits data recovery options
a bit. I wouldn't buy one of those! Just the thought of the
resulting hair loss, is enough to keep me away from them.

Â*Â* Paul


I tore one apart a few weeks ago to recover data from it.
Still a SATA drive, but a really old one. If memory
serve's me right, it was a 500 GB unit.

Straight USB now. Saves money, but I really hope they
improve the interface's reliability.


  #9  
Old January 25th 19, 06:24 AM posted to alt.comp.os.windows-10
Paul[_32_]
external usenet poster
 
Posts: 11,873
Default I need help!

Dan Purgert wrote:
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

lonelydad wrote:
Keith Nuttle wrote in news:q2dall$1dar$1
@gioia.aioe.org:

On 1/24/2019 1:02 PM, lonelydad wrote:
Paul in Houston TX wrote in
:

lonelydad wrote:
I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File
Explorer will show the two partitions, but won't open them. Is

there
some utility I can use to rebuild the file tables or whatever so I
can access the data?
It is an encrypted Passbook?

no

Dumb question: Was this drive the main drive in another computer, and
could the inaccessible partitions be system partitions when it was
the main drive with the OS on it?

If there is no data on the drive you could reformat in in make it one
large partition.

You may check the Disk Management (Right click the Windows Icon on the
left end of the tool bar and see what it says about the questionable
partitions)

I believe there is software to attach Drive letters to those

partition,
so File explorer can see them.



I had two questinable hard drives on my PC. I copied the contents of
those two drives to two partions on this external USB drive. I did not
get a chance to restore the contents to regular hard drives [SATA]
before it started acting up.

Disk Management will sometimes see the device, but the partitions are
undefined. If I put my hand on the box I can feel the heads seeking
constantly. I won't die if I don't get the data back, but there is a lot
of stuff I spent a long time collecting that I will miss and probably
can't recreate.


It's a longshot, and will be markedly harder because it's USB, but toss
it in a freezer bag with some dessicant packets for say overnight. Then
stick that whole package in the freezer before you leave for work.

I've had a few successes with freezing dying harddrives. It doesn't
always work, but sometimes it's just the ticket.

Don't try to recover right from the drive -- use something to as quickly
as possible make an image of the drive, then work off the image (I'm
primarily a Linux guy, so ddrescue comes to mind ... unfortunately, I
don't know of any Win equivalents).

Once you've got the drive image to work from, recover data from that
(depending on the tool, may require a new drive to write the image to --
think burning an ISO to CD/DVD). Lot safer working from an image on a
known-good (or brand new )drive than it is trying to poke around a
dying drive trying to remember where you stuck that paper / music /
whatever.


HTH.


Don't do that!

He's a long way from declaring defeat. On a drive with a 3nm
flying height, the freezer would be "death".

The first step, is to acquire sufficient disk(s) for recovery,
then *immediately* clone the drive in question.

1) Boot a Linux LiveCD. This is necessary so the OS will
*leave the damn disk alone*. (If in Windows, you could try
setting the sick drive "offline" and using the Windows dd.
The syntax is different, but the info page will give all
the details you need to be successful. I don't know if
"offline" status blocks dd.exe or not.)

http://www.chrysocome.net/dd

http://www.chrysocome.net/downloads/dd-0.6beta3.zip

2) Clone from USB drive to SATA drive of matching size or larger
than the malfunctioning drive. Then, open a Terminal and try...

gnome-disks # Ask OS for install instructions.

sudo gnome-disks # Use this program to display disk information,
# so you know you're cloning /dev/sdb to /dev/sdc
# for example

gparted # Ask OS for install instructions.

sudo gparted # Run gparted, again, as a way to display
# the particulars, correlated against the sdX value
# You want to make sure you're cloning the right disk.

3) Now, in terminal, transfer the bad disk to the good disk.

sudo dd /dev/sdb /dev/sdc bs=8192

4) Optional but useful: Open a second terminal.

iotop # Ask OS for install instructions

sudo iotop # Displays instantaneous transfer speed

Open a third terminal.

sudo iotop -a # Count the transferred bytes, so you have
# some idea how long it will take.

If the source disk is sick, the statistics gathered in the
display will reflect the problem. A USB2 disk or USB2 port on
a computer, will transfer at 30 to 35MB/sec. Whereas the hard drive
inside the enclosure, goes faster than that.

The command in (3) stops when it runs out of source
material to copy. If you copy a 3TB disk to a 4TB disk,
the source runs out first and the transfer stops when
3TB of work is done. Every sector is copied, not the best
thing, but good when a partition refuses to be recognized and
you want a copy, to be sure you don't lose the files. That's
why we're doing this! On a sick disk, it's no time to be
doing CHKDSK, and you want a nice smooth clone to save the
data. Interpreting the data after the transfer is done,
would be the contents of a second post.

Note: If the transfer stops on a "CRC error", then you need
to use the gddrescue package. That's a transfer method
that can be run more than once, to "build up" the
captured sectors, and make multiple tries to read
the source.

sudo apt install gddrescue

man ddrescue

sudo ddrescue /dev/sdb /dev/sdc somelogfile.txt

The logfile keeps track of which sectors have been
transferred. Check the manual page for more details.
On the "second pass", the logfile is read first, to
figure out which sectors remain to be transferred.

That's a basic hint, if the "dd" one isn't good enough.

If this happened here in my little computer room, I would
probably start with gddrescue, rather than making a botched
run and then doing ddrescue after that.

I've only tested ddrescue once here, and since the drives
were healthy, the log was empty, and no subsequent runs
would (of course) transfer anything. When the logfile is
empty, and it is read in, the program knows there is nothing
to do, so it quits.

In this example, I'm cloning a drive, into a *file*. I can
later transfer the bitmap file, back onto a second drive.

sudo ddrescue -b8M /dev/sdb /mount/external/backup/sdb.raw /mount/external/backup/sdb.log

I could restore to a new drive with either of these, because I know
both disks involved are healthy and I don't need ddrescue. So
this is an example of a kind of "drive imaging" before putting
the image back onto the newly purchased disk.

sudo dd if=/mount/external/backup/sdb.raw /dev/sdc bs=8192

ddrescue -b8M /mount/external/backup/sdb.raw /dev/sbc lame.log

*******

If there was a reliable way to do this, without spending
money, I'd be promoting it... One utility we might have
used, seems to cheat, and is likely to quit when it can't
access the partitions.

I don't have any suitably sick drives here to test with.
I have sick drives, but... no CRC errors to work with.

HTH,
Paul
  #10  
Old January 25th 19, 10:06 AM posted to alt.comp.os.windows-10
Dan Purgert
external usenet poster
 
Posts: 281
Default I need help!

Paul wrote:
Don't do that!

He's a long way from declaring defeat. On a drive with a 3nm
flying height, the freezer would be "death".


Hm, have never had a problem with the freezer before. Then again, maybe
I've just been lucky.

That being said, it has been the better part of a decade since the last
time "dying drive" caught me unprepared.


--
|_|O|_|
|_|_|O| Github: https://github.com/dpurgert
|O|O|O| PGP: 05CA 9A50 3F2E 1335 4DC5 4AEE 8E11 DDF3 1279 A281
  #11  
Old January 27th 19, 08:13 PM posted to alt.comp.os.windows-10
Travis Bickle[_2_]
external usenet poster
 
Posts: 2
Default I need help!

On 1/24/19 12:53 AM, lonelydad wrote:
I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File Explorer
will show the two partitions, but won't open them. Is there some utility I
can use to rebuild the file tables or whatever so I can access the data?

Next time, try a helpful Subject Line like "WD USB Drive Trashed"
instead of wailing like an infant...

--
You can’t get rich in politics unless you’re a crook.
- President Harry Truman
  #12  
Old January 30th 19, 12:42 AM posted to alt.comp.os.windows-10
Tim[_10_]
external usenet poster
 
Posts: 249
Default I need help!

lonelydad wrote in
.28:

I have a WD Passbook 4tb USB drive. I can get the system to see the
hardware, but the two partitions on it aren't accessible. File
Explorer will show the two partitions, but won't open them. Is there
some utility I can use to rebuild the file tables or whatever so I can
access the data?


Magic Still Happens!

Wonder of wonders I plugged the bad USB drive in yesterday, and it came
up! You better believe the first thing I did was move all the files back
to hard drives on my system! So I have everything back, and a
questionable USB drive.

Two things happened that might have made the difference. One, I finally
got my system upgraded. I had been on 1709 because I could never get 1803
to install properly. So I downloaded 1809(181) to a thumb drive and ran
setup from there. Everything installed properly so that hurdle is passed.
Second, I have two sets of USB 3 ports on the front of my PC. The one
came with the case, and I think it is setup as a 4 port hub. The other I
added, and it is set up as two 2 port hubs. Up until yesterday, when I
plugged my USB drive into the original set of ports, the indicator lite
showing an active port didn't come on, so I was using the ports I added.
When I plugged in the drive yesterday I tried the original ports again,
and this time the indicator light came on, and the drive came up with no
problems, and so far has stayed up. So maybe the problem was with
insufficient power available. This would go along with the behavior of
the drive. I would keep showing up and then disappearing again. Even when
it didn't appear to the system, I could feel the heads trying to load.
Either way, I'm happy things turned out OK. I think I will run a
benchmark and surface test on the USB drive to see how it holds up before
I trust it again.

Thanks to all of you for your suggestions and attempts to help.
  #13  
Old January 30th 19, 03:16 AM posted to alt.comp.os.windows-10
Paul[_32_]
external usenet poster
 
Posts: 11,873
Default I need help!

Tim wrote:
lonelydad wrote in
.28:

I have a WD Passbook 4tb USB drive.


So maybe the problem was with
insufficient power available. This would go along with the behavior of
the drive. I would keep showing up and then disappearing again. Even when
it didn't appear to the system, I could feel the heads trying to load.


On 2.5" drives, they draw around 1000mA from the 500mA USB2 port.
This can cause the Polyfuse (rated at 1100mA) to open.

Polyfuses are polycrystalline. They become liquid phase when the current
flow is too high. When the overload is removed and they cool off, the
material hardens back into a crystal.

It's better if an external hard drive is powered by an
external source, but they don't always put a barrel
connector on the external drive casing.

Just one of those "electrical disaster areas" some
group of people thought was a fine idea.

Once the drive is spinning, power demand drops, sometimes
even below the 500mA level. The drive can then continue
spinning. But for drives with "parking habits", they will
stop, then start moments later, applying the "trial by fire"
to the Polyfuse again.

At the very least, on a desktop, you should not put two heavy
electrical loads on the same "stack-of-two" USB2 ports. And even then,
the numbers involved are a "close thing".

There are some SSDs in 2.5" form factor, which will work OK
with the USB2 port. There are a few brands though, which
go "over the top" when compressing data, that you'd want to
avoid if crafting your own home-brew external backup device.

As often as not, I move my backup devices inside the desktop,
where the power is guaranteed. It's not as often that I go external,
and I also use an external supply with a couple of my enclosures,
and that helps guarantee sufficient power.

This is a 3.5" enclosure, but it would accept a 2.5" drive because
the SATA connector is the same on those two items. If a device
has a high power dissipation, I also leave off the aluminum casing
and just run the drive using the adapter PCB, USB cable and power
adapter.

https://sgcdn.startech.com/005329/me...0SMU33.bom.jpg

Paul

  #14  
Old January 30th 19, 03:55 AM posted to alt.comp.os.windows-10
Mike
external usenet poster
 
Posts: 185
Default I need help!

On 1/29/2019 6:16 PM, Paul wrote:
Tim wrote:
lonelydad wrote in
.28:
I have a WD Passbook 4tb USB drive.


So maybe the problem was with insufficient power available. This would
go along with the behavior of the drive. I would keep showing up and
then disappearing again. Even when it didn't appear to the system, I
could feel the heads trying to load.


On 2.5" drives, they draw around 1000mA from the 500mA USB2 port.
This can cause the Polyfuse (rated at 1100mA) to open.

Polyfuses are polycrystalline. They become liquid phase when the current
flow is too high. When the overload is removed and they cool off, the
material hardens back into a crystal.


A polyfuse cold resistance increases substantially the first time it opens.
Subsequent openings further increase it at a lower rate. It's in the
specification.
Back in the day, I had to build an outboard box inline with the USB
to power external drives from laptops that couldn't.

It's better if an external hard drive is powered by an
external source, but they don't always put a barrel
connector on the external drive casing.

Just one of those "electrical disaster areas" some
group of people thought was a fine idea.

Once the drive is spinning, power demand drops, sometimes
even below the 500mA level. The drive can then continue
spinning. But for drives with "parking habits", they will
stop, then start moments later, applying the "trial by fire"
to the Polyfuse again.

At the very least, on a desktop, you should not put two heavy
electrical loads on the same "stack-of-two" USB2 ports. And even then,
the numbers involved are a "close thing".

There are some SSDs in 2.5" form factor, which will work OK
with the USB2 port. There are a few brands though, which
go "over the top" when compressing data, that you'd want to
avoid if crafting your own home-brew external backup device.

As often as not, I move my backup devices inside the desktop,
where the power is guaranteed. It's not as often that I go external,
and I also use an external supply with a couple of my enclosures,
and that helps guarantee sufficient power.

This is a 3.5" enclosure, but it would accept a 2.5" drive because
the SATA connector is the same on those two items. If a device
has a high power dissipation, I also leave off the aluminum casing
and just run the drive using the adapter PCB, USB cable and power
adapter.

https://sgcdn.startech.com/005329/me...0SMU33.bom.jpg


Â*Â* Paul


  #15  
Old January 30th 19, 05:00 AM posted to alt.comp.os.windows-10
Paul[_32_]
external usenet poster
 
Posts: 11,873
Default I need help!

Mike wrote:
On 1/29/2019 6:16 PM, Paul wrote:
Tim wrote:
lonelydad wrote in
.28:
I have a WD Passbook 4tb USB drive.


So maybe the problem was with insufficient power available. This
would go along with the behavior of the drive. I would keep showing
up and then disappearing again. Even when it didn't appear to the
system, I could feel the heads trying to load.


On 2.5" drives, they draw around 1000mA from the 500mA USB2 port.
This can cause the Polyfuse (rated at 1100mA) to open.

Polyfuses are polycrystalline. They become liquid phase when the current
flow is too high. When the overload is removed and they cool off, the
material hardens back into a crystal.


A polyfuse cold resistance increases substantially the first time it opens.
Subsequent openings further increase it at a lower rate. It's in the
specification.
Back in the day, I had to build an outboard box inline with the USB
to power external drives from laptops that couldn't.


Desktops use Polyfuses.

Laptops use an eight pin DIP with FETs in it.
Those have a "sharp" characteristics, and are
also likely to prematurely cut power (not as
forgiving as the desktop fusing scenario).

At a guess, Polyfuses are used in desktops, because
there is air circulation around them. The eight pin
DIPs used in laptops to cut the power, would presumably
be less sensitive to ambient temperature. If the laptop
one had dead air around it, it would still be as sharp
and crispy as before.

Paul


Paul
 




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