12v adapter for laptop?

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

Lou_tribal

Guru
Joined
Jan 20, 2016
Messages
4,375
Location
Canada
Vessel Name
Bleuvet
Vessel Make
Custom Built
Hi folks,
This weekend I realized that the only thing that sucks aboard is not being able to recharge my laptop without the generator running. I am wondering if anybody knows about a 12v DC adapter I could use?
I know I could use an inverter to get 110v and connect the laptop on it but would be better to avoid 12 to 110 and 110 to 19 conversion.

L
 
I use one of those very small inverters (150 watts) for this operation. They draw very little in this size and plug into a standard 12. power port. Convenient small, and inexpensive.....
 
Depending on you laptop and its power requirements as to determine which DC adapter to buy. I have two different ones on our boat one powers a Dell and one powers a Panasonic Toughbook. I purchased from PWR Plus.
 
Check with the mfg. I know Dell offered a dc charger for some of there laptops.
 
Do a search for 12V chargers for your laptop make & model.
I just purchased obe for my Lenovo laptop and was also a Power+
I also just picked up a recepticle that fits in a std electrical box and contains a 12V recepticle and 2 USB ports for charging.
My plan us to replace the never used wired phone outlet in my Mainship salon and wire it to a 12V source. Location was perfect for where I use the laptop and access to a 12V supply fairly easy.
I considered the inverter route but figured why go through double conversions
 
Last edited:
I have done it mostly with a small inverter but also tried a cheap Chinese 12V to 19V converter. The DC requirements were the same and the converter finally failed- cheap Chinese s*&^.

So unless you pay for a high quality voltage converter that might be slightly more efficient (but why sweat a 1/4 amp) and won't fail, stick with the inverter.

David
 
No need for an inverter. I bought a cable for my Dell laptop that had an auto-style cigarette lighter plug. I simply cut that off and wired directly to a 12 volt circuit on the dash.
 
I’ve been using this for 4 years and no problems.
 

Attachments

  • 6324C9F1-8DAE-4212-B9A8-921965764F44.jpg
    6324C9F1-8DAE-4212-B9A8-921965764F44.jpg
    169 KB · Views: 58
I have done it mostly with a small inverter but also tried a cheap Chinese 12V to 19V converter. The DC requirements were the same and the converter finally failed- cheap Chinese s*&^.

So unless you pay for a high quality voltage converter that might be slightly more efficient (but why sweat a 1/4 amp) and won't fail, stick with the inverter.

David

You are lucky that is all it did. Think about this. You have a computer, tablet or phone worth hundreds of $ with perhaps invaluable information on it and you plug it into a cheap uncertified POS? Do not buy your chargers of unknown quality at the Dollar Store!
Apple is written on every information device I own. I use 12v dual usb cigar lighter plug in chargers. They come from Amazon and are Apple Certified. About $20 each. 1 in each car and 2 on the boat. AC Apple only. Using Cheap chargers and inverters that can malfunction and let the smoke out of your expensive equipment is not wise. It happens.
Another thought, batteries act as a filter. The grid is subject to surges. Batteries, not so much. Square-modified wave inverters hammer your equipment. Dc is smooth, no sine wave.
 
Last edited:
You are lucky that is all it did. Think about this. You have a computer, tablet or phone worth hundreds of $ with perhaps invaluable information on it and you plug it into a cheap uncertified POS? Do not buy your chargers of unknown quality at the Dollar Store!
....
Another thought, batteries act as a filter. The grid is subject to surges. Batteries, not so much. Square-modified wave inverters hammer your equipment. Dc is smooth, no sine wave.

The battery in the laptop also acts as a filter.

Also, as everybody should know, don't keep all your digital information in one place. Even with the best power available, a laptop, computer, or any other electronic device can fail at any time. On a boat there is also the possibility that the boat could sink and take all your info with it.
 
All you need is a 12v cigarette lighter outlet, and a plug with a USB outlet. Cigarette lighter outlets may not be the best outlets, hardly any get used for the original purpose, but they can power lots of 12v gear.
 
The battery in the laptop also acts as a filter.

Also, as everybody should know, don't keep all your digital information in one place. Even with the best power available, a laptop, computer, or any other electronic device can fail at any time. On a boat there is also the possibility that the boat could sink and take all your info with it.

Good point.
 
Targus, Kensington and others have made various universal auto power supplies for a while. Check around and see if they make one and the adapter tip to work with your model device.

As has been suggested, check on your laptop's vendor website and see if they offer anything for auto/airplane use. HP and Dell typically have something, others may as well.

Using a DC-AC inverter is 'less than ideal' because it'd likely consume more power than necessary and generate a fair bit of heat in the process.

At some point trying to make an older laptop continue to work exceeds the cost and benefits of a new one. Might be worth taking that into consideration.
 
Random thoughts....
Your generator only outputs 12 volts?? I thought they all put out 120 volts. Learned something new !!

Check the manufacturer of the laptop to see if they have a 12 V charger.

Also 12 volts in a car, truck, RV, or boat is not always 12 volts. When the engine alternator is running it's more like 13.6 volts. Small difference but something to be aware of with any electronics. Also there is a bit of a voltage surge ( up and down ) when starting an engine that can mess with the electronics. Just make sure your method of charging takes that into account. And it pays to use a good charger for that reason...


Some tablets and most cell phones I believe use the USB chargers. Some plug into 120 with a stepdown to 12 V or the USB plug can go into a 12 V cigarette lighter type plug. They lower the voltage to around 5 volts. Pretty universal now and works...
 
I have one I found at Radio Shack that simply plugs into a Cig style outlet. It powered my laptop successfully for several seasons, after a cheap 75 watt inverter let out its smoke.
If you use this approach, check the polarity of your cig outlet. I have my GPS connected to my laptop for navigation, by USB. the GPS connection let out its own smoke on that connection because the polarity of the GPS connection (hard wired) and the power to the laptop were not the same!
I went back to a new 150w inverter to the laptop, no worries and a pair of AC outlets always available.
 

Latest posts

Back
Top Bottom