How to charge Dell laptop from 12V cigarette socket

[kje]

I wanna charge a Dell Latitude E6500 laptop from the cigarette socket (12V), and have now tried two Vanson laptop adapters (SDR-100W and SDR-120W). Both deliver a weak beeping and does not charge the laptop battery.

According to the regular power adapter the Laptop need 19.5V and 4.62A. On the laptop battery it says 19.5V and 3.5A minimum and 4.62A max.

Vanson SDR-100W http://www.ebay.com/itm/Vanson-Auto...=Laptop_Adapters_Chargers&hash=item337482e4a4 delivers 4.5A at 18/19/20V (you can switch between 18,19 and 20V). The plug fits into the power socket on the laptop and have "positive tip polarity."

Vanson SDR-120W http://www.clasohlson.com/no/Batteri...0W/Pr381383000 delivers up to 6A and can switch between 18,19 and 20V.

I bougth both the Vansons on a local shop here in Norway called Claes Ohlson.

Why do none of these charge my laptop battery?

 

[heathyoung]

Easy - the Dell laptop chargers have a 3 pin IC that identifies itself to the laptop as a genuine charger.

You to find one that is Dell compatible, they did make one for use on planes + cars (Dell).

 

[dnmun]

if you have the dell laptop adapter, you can get a 12V DC-120V AC inverter and run the dell adapter from that. i knew someone who used that to keep a lot of things charged while in his car.

 

[kje]

Easy - the Dell laptop chargers have a 3 pin IC that identifies itself to the laptop as a genuine charger.

You to find one that is Dell compatible, they did make one for use on planes + cars (Dell).

I think mine has just two... plus and minus. This is my usual wall adapter:

I have another wall adapter; Vanson SMP-120W like this:

,
and that works with the same connection into the laptop as I tried with the SDR-100W and SDR-120W.

So why won`t the SDR-100W or SDR-120W charge the laptop? Is it because of wrong power spesifications? Or is it the plug?

 

[kje]

I don't wanna use inverter because bad efficiency.
Any suggestions?

 

[major]

I know that my Dell laptop uses a special octagonal (not round) plug from the adapter. I has 3 connects, center pin, outside barrel and inside barrel. I have an external 19V battery supply I wanted to use with it. I had to buy the genuine replacement plug and then splice onto my charge cable from my battery supply. That only had 2 wires. So I found the 2 of 3 wires from the octo plug and spliced. So it works with the external battery to power the computer, but it will not charge from the external battery. I suppose I need to connect that 3rd wire, but I was unsure where, didn't really need to and didn't want to press my luck. Just powering it from the external battery suits my needs.

I saw a lot of different charge adapters for Dells when I was looking. Uncertain what I said applies to yours. But I think generally, laptop adapters use only 2 wires and those automotive things are 2 wire.

 

[marty]

I don't wanna use inverter because bad efficiency.
Any suggestions?

Running a gasoline engine capable of moving a 4000 pound car 100 miles per hour to spin a alternator to make 12VDC is bad efficiency. If car is driving or idling, I would not worry about efficiency and use a 12V DC to 120V AC inverter.

 

[kje]

I know that my Dell laptop uses a special octagonal (not round) plug from the adapter. I has 3 connects, center pin, outside barrel and inside barrel. I have an external 19V battery supply I wanted to use with it. I had to buy the genuine replacement plug and then splice onto my charge cable from my battery supply. That only had 2 wires. So I found the 2 of 3 wires from the octo plug and spliced. So it works with the external battery to power the computer, but it will not charge from the external battery. I suppose I need to connect that 3rd wire, but I was unsure where, didn't really need to and didn't want to press my luck. Just powering it from the external battery suits my needs.

I saw a lot of different charge adapters for Dells when I was looking. Uncertain what I said applies to yours. But I think generally, laptop adapters use only 2 wires and those automotive things are 2 wire.

Interresting. Did your plug look like mine? Do you have picture? The plug on my Dell power supply look like this:

Running a gasoline engine capable of moving a 4000 pound car 100 miles per hour to spin a alternator to make 12VDC is bad efficiency. If car is driving or idling, I would not worry about efficiency and use a 12V DC to 120V AC inverter.

I would be happy to use my laptop direct from a 12V battery (not necessarily in a car).

 

[dnmun]

you can buy the small boost converters on ebay for real cheap. from 12V to ~18V is a boost converter and i remember seeing one with 3A output and heatsinks for $18. go look on ebay.

 

[kje]

you can buy the small boost converters on ebay for real cheap. from 12V to ~18V is a boost converter and i remember seeing one with 3A output and heatsinks for $18. go look on ebay.

I tried exactly this. I bought a DC DC boost converter and adjusted the output voltage to 19.5V (like my laptop power supply voltage), but it didn`t work?

Btw the DC DC boost converter made some noise, is that normal?

 

[major]

I'll try to paste it. http://www.chargerbuy.com/blog/files/2011/01/dell-inspiron-1545-adapter-octagonal-300x205.jpg Hopefully that is a photo of two plugs.

 

[kje]

I'll try to paste it. http://www.chargerbuy.com/blog/files/2011/01/dell-inspiron-1545-adapter-octagonal-300x205.jpg Hopefully that is a photo of two plugs.

Okey. I use the plug to the left on your picture (the round one). Did you say it is 3 wires inside the cable?

Edit: I now tried with two other laptops without battery (HP and Acer) with my DC DC step up converter and it worked. I tried without the battery in my Dell laptop and that worked as well. But I got a power warning at startup, and it won't charge the battery as you said. I wonder if there is a workaround for that?

 

[major]

I'll try to paste it. http://www.chargerbuy.com/blog/files/2011/01/dell-inspiron-1545-adapter-octagonal-300x205.jpg Hopefully that is a photo of two plugs.

Okey. I use the plug to the left on your picture (the round one). Did you say it is 3 wires inside the cable?

Yes, white, black and red. Black to outside of barrel, white to inside surface of barrel and red to the center pin. I put 19V positive to white wire and negative to black and leave red disconnected. It powers my Dell but does not charge the laptop battery.

 

[dnmun]

i don't even have a battery in my laptop since i just use it for a keyboard but the best way to make you laptop battery last a long time is to only charge it up when you need to use the laptop in mobile.

it is best to run your battery down to the alarm level and then plug in the charger and then remove your battery from the laptop and then use the laptop on the charger. do not recharge the battery.

that keeps your laptop battery alive for years and years so it is able to handle the times it is used in mobile mode.

 

[kje]

I'll try to paste it. http://www.chargerbuy.com/blog/files/2011/01/dell-inspiron-1545-adapter-octagonal-300x205.jpg Hopefully that is a photo of two plugs.

Okey. I use the plug to the left on your picture (the round one). Did you say it is 3 wires inside the cable?

Yes, white, black and red. Black to outside of barrel, white to inside surface of barrel and red to the center pin. I put 19V positive to white wire and negative to black and leave red disconnected. It powers my Dell but does not charge the laptop battery.

Ok. Is it impossible to charge the battery on a Dell laptop from 12V?

 

[marty]

No not impossible. Suspect the red wire does something. Got to figure out what? Test.

Look here:
Inside the DELL AC Power Adapter - A mystery revealed
http://www.laptop-junction.com/toast/content/inside-dell-ac-power-adapter-mystery-revealed

I would give up and use a 12V DC to 120V AC inverter.

 

[major]

Look here:
Inside the DELL AC Power Adapter - A mystery revealed
http://www.laptop-junction.com/toast/content/inside-dell-ac-power-adapter-mystery-revealed

Thanks. I guess I'll leave the red wire/center pin alone and be content with being able to power the computer from my external battery.

 

[oldhaq]

Don't bother trying to "jack" the middle pin, it just carries a data signal to enable charging
A while ago I swapped out the "transistor" looking device from a dead charger to one that had power but not charging to get it working again.
Most of the aftermarket adapters will power but not charge because they don't have this device.
You want a car or air adapter, Dell part number D09RM
Depending on your laptop's current draw, you might want to only charge with the laptop off, then remove battery when in use.

 

[bikeelectric]

I used a Targa 12v laptop power supply on a Dell laptop once. The model Dell I had wasn't listed by Targa but the plug fit in it. Worked for awhile until the smoke came out of the Targa adapter - and an abundant amount of smoke !
I got a warranty replacement for the Targa and it would not power up the laptop at all - guess Targa had figured out that certain model Dells were not compatible and one of the wires to the jack was not connected.
As someone else said - there is some kind of data that the laptop or battery senses from the charger . Best to do as others have said and use either manufacturers 12v adapter or else use 12v inverter for supplied Dell AC charger . Sure you loose some efficiency but it will work and no smoke !

 

[kje]

Thanks. Like major I'll leave the red wire/center pin alone and be content with being able to power the computer from my external battery.

 

[cal3thousand]

Easy way is to get a 12V inverter that is rated for more than 150W

http://www.amazon.com/BESTEK®-Inverter-Adapter-Charger-Notebook/dp/B0040U3MI8