Laptop car adapter question

G

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Archived from groups: comp.sys.laptops (More info?)

I am planning on purchasing a car adapter for my laptop. I read a few
posts on this newsgroup about keeping the laptop's car adapter
unplugged from the car's cigarette lighter outlet before starting the
car, then plugging it in once the car has started.

I was wondering if I should also shutdown the laptop and unplug it from
the cigarette lighter outlet *before* turning the car *off*? Are there
any risks if I don't unplug it before turning the car off?

Thanks
 

Charlie

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On 26 Nov 2004 16:32:26 -0800, "Sm704" <sm7040@hotmail.com> wrote:

>I am planning on purchasing a car adapter for my laptop. I read a few
>posts on this newsgroup about keeping the laptop's car adapter
>unplugged from the car's cigarette lighter outlet before starting the
>car, then plugging it in once the car has started.
>
>I was wondering if I should also shutdown the laptop and unplug it from
>the cigarette lighter outlet *before* turning the car *off*? Are there
>any risks if I don't unplug it before turning the car off?
>
>Thanks

Another thing you might want to consider is to get one of those units
that contain a 12 v gell-cell battery, and are rated for enough amps
to use as a spare battery for restarting the car. The one I got also
contains a light and a small air pump, so it's a handy item to have
for safety. You can then use the 12 v "lighter" socket on this unit as
the power source for your laptop, and never have to worry about
transient voltage spikes brom you cars circuits damaging the laptop.
You simply connect the gell-cell unit to a 110 v charger or to the
automobile when the laptop is not connected, to recharge the unit.
---
Charlie Hoffpauir
http://freepages.genealogy.rootsweb.com/~charlieh/
 
G

Guest

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Archived from groups: comp.sys.laptops (More info?)

>I am planning on purchasing a car adapter for my laptop. I read a few
>posts on this newsgroup about keeping the laptop's car adapter
>unplugged from the car's cigarette lighter outlet before starting the
>car, then plugging it in once the car has started.
>
>I was wondering if I should also shutdown the laptop and unplug it from
>the cigarette lighter outlet *before* turning the car *off*? Are there
>any risks if I don't unplug it before turning the car off?
>
>Thanks

The extra wear is on the power adapter not the notebook. From the
voltage surge when starting or stopping the cars engine. The power
adapter,(of which I have several from Rado Shack) all have regulated
power out. No matter how much you rev the engine, start or stop it,
the output stays the same. Anyone with a $5 voltmeter can test this. I
know it's true since both my notebooks need the exact voltage or they
won't recognize or even connect to outside power. Starting or stopping
the engine never causes the charge indicator light to go out so the
supply is not varried.
 

Samurai

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Jun 20, 2002
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I use a 12v to 120 volt inverter, be sure to get one that has enough
watts. I keep it in the back under the seat, with a wire to the 12v
cigarette plug, or it could be wired directly to 12v system. Then a
short household extension cord from the inverter to the front seat
where I need my laptop.

Now you can use this for any 120v device, in any vehicle.

samurai.


On Fri, 26 Nov 2004 19:00:14 -0600, Charlie <invalid@invalid.com>
wrote:

>On 26 Nov 2004 16:32:26 -0800, "Sm704" <sm7040@hotmail.com> wrote:
>
>>I am planning on purchasing a car adapter for my laptop. I read a few
>>posts on this newsgroup about keeping the laptop's car adapter
>>unplugged from the car's cigarette lighter outlet before starting the
>>car, then plugging it in once the car has started.
>>
>>I was wondering if I should also shutdown the laptop and unplug it from
>>the cigarette lighter outlet *before* turning the car *off*? Are there
>>any risks if I don't unplug it before turning the car off?
>>
>>Thanks
>
>Another thing you might want to consider is to get one of those units
>that contain a 12 v gell-cell battery, and are rated for enough amps
>to use as a spare battery for restarting the car. The one I got also
>contains a light and a small air pump, so it's a handy item to have
>for safety. You can then use the 12 v "lighter" socket on this unit as
>the power source for your laptop, and never have to worry about
>transient voltage spikes brom you cars circuits damaging the laptop.
>You simply connect the gell-cell unit to a 110 v charger or to the
>automobile when the laptop is not connected, to recharge the unit.
>---
>Charlie Hoffpauir
>http://freepages.genealogy.rootsweb.com/~charlieh/
 
G

Guest

Guest
Archived from groups: comp.sys.laptops (More info?)

The risks here are primarly to the car adapter rather than the laptop.
There are some pretty significant spikes on a car electrical system
during both starting and shutdown, they are worse during starting thanks
to the starter motor. The truth is that a modern adapter should handle
all of these on both starting and shutdown, but the real world might not
be so tolerant. However, the adapters are switching power supplies, and
the isolation of the output that goes to the laptop from the input (car
electrical bus) is nearly total. Also, there is a LOT of electronic
equipment in the car that is ALWAYS connected to the electrical bus,
including the car radio, several computers and possibly a navigation
system, and they all handle all of this stuff without any problems.
It's not like car adapters were not designed with this environment in
mind, which is why they should handle it with no special precautions or
"babying".


Sm704 wrote:

> I am planning on purchasing a car adapter for my laptop. I read a few
> posts on this newsgroup about keeping the laptop's car adapter
> unplugged from the car's cigarette lighter outlet before starting the
> car, then plugging it in once the car has started.
>
> I was wondering if I should also shutdown the laptop and unplug it from
> the cigarette lighter outlet *before* turning the car *off*? Are there
> any risks if I don't unplug it before turning the car off?
>
> Thanks
>
 

Mike

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Apr 1, 2004
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0
18,930
Archived from groups: comp.sys.laptops (More info?)

AndrewJ wrote:
>
>>I am planning on purchasing a car adapter for my laptop. I read a few
>>posts on this newsgroup about keeping the laptop's car adapter
>>unplugged from the car's cigarette lighter outlet before starting the
>>car, then plugging it in once the car has started.
>>
>>I was wondering if I should also shutdown the laptop and unplug it from
>>the cigarette lighter outlet *before* turning the car *off*? Are there
>>any risks if I don't unplug it before turning the car off?
>>
>>Thanks
>
>
> The extra wear is on the power adapter not the notebook. From the
> voltage surge when starting or stopping the cars engine. The power
> adapter,(of which I have several from Rado Shack) all have regulated
> power out. No matter how much you rev the engine, start or stop it,
> the output stays the same. Anyone with a $5 voltmeter can test this.

The stuff you can see with a voltmeter is the least of your worries.

http://www.littelfuse.com/data/en/Application_Notes/an9312.pdf
mike


I
> know it's true since both my notebooks need the exact voltage or they
> won't recognize or even connect to outside power. Starting or stopping
> the engine never causes the charge indicator light to go out so the
> supply is not varried.



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