Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 14-04-2011, 20:47   #1
Registered User

Join Date: Nov 2005
Location: Tasmania
Boat: VandeStadt IOR 40' - Insatiable
Posts: 2,317
Images: 91
Running a Laptop Without an Inverter

Given the power losses with converting DC to AC and then the losses with converting it right back to DC again, I have never been a big fan of using an inverter to run a laptop.

My previous laptop would run quite fine from a standard 12V DC cigarette-lighter type outlet using a DC-DC adaper, with adjustable output, so I would just set it to the required voltage (16V, from memory) and off we'd go.

My new laptop, apparently, has some sensor in the power inlet and won't allow me to do this. So at this stage a small (150W) inverter looks like the only solution...

Any alternatives?
Weyalan is offline   Reply With Quote
Old 14-04-2011, 20:56   #2
always in motion is the future
 
s/v Jedi's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: in paradise
Boat: Sundeer 64
Posts: 18,864
Re: Running a laptop without an inverter

Quote:
Originally Posted by Weyalan View Post
Given the power losses with converting DC to AC and then the losses with converting it right back to DC again, I have never been a big fan of using an inverter to run a laptop.

My previous laptop would run quite fine from a standard 12V DC cigarette-lighter type outlet using a DC-DC adaper, with adjustable output, so I would just set it to the required voltage (16V, from memory) and off we'd go.

My new laptop, apparently, has some sensor in the power inlet and won't allow me to do this. So at this stage a small (150W) inverter looks like the only solution...

Any alternatives?
Don't worry too much... a DC-DC converter also uses AC as an intermediate step with comparable (but lower) losses. Those losses are for a large part relative to the unit's maximum power output, meaning you're better off with a small inverter as long as the laptop is the only device needing AC power.

ciao!
Nick.
s/v Jedi is offline   Reply With Quote
Old 14-04-2011, 23:39   #3
cruiser

Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
Re: Running a laptop without an inverter

Quote:
Originally Posted by Weyalan View Post

My new laptop, apparently, has some sensor in the power inlet and won't allow me to do this. So at this stage a small (150W) inverter looks like the only solution...

Any alternatives?
What laptop is it? How would it know, I wonder. Dc is dc innit?
In the UK a lot of people use these on boats - 150W Laptop Car Adaptor : InCar Power Adaptors : Maplin
On my toshiba it draws maybe about 60% compared to the invertor.
conachair is offline   Reply With Quote
Old 15-04-2011, 00:24   #4
Registered User
 
sctpc's Avatar

Join Date: Jul 2008
Location: Melbourne Australia
Boat: saga kan walker 31ft
Posts: 545
Send a message via Skype™ to sctpc
Re: Running a laptop without an inverter

I bought a 19v one of TOSHIBA CAR CHARGER ADAPTER SATELLITE P200 PRO A100 L10 | eBay He has all types and they work.

I dont know the guy I just found him for my problem
__________________
May there always be water under your boat,

sctpc is offline   Reply With Quote
Old 15-04-2011, 00:53   #5
Registered User
 
richardhula's Avatar

Join Date: Nov 2008
Location: UK
Boat: S M Hudson 60' narrowboat
Posts: 347
Send a message via Skype™ to richardhula
Re: Running a laptop without an inverter

Quote:
Originally Posted by conachair View Post
What laptop is it? How would it know, I wonder. Dc is dc innit?
In the UK a lot of people use these on boats - 150W Laptop Car Adaptor : InCar Power Adaptors : Maplin
On my toshiba it draws maybe about 60% compared to the invertor.
DC is DC yes but your laptop will require a specific voltage usually above the nominal 12 volts available on your boat.

Walmart among others offer DC-DC laptop chargers with variety of power connector heads & adjustable output voltage to suit almost every laptop made. Just check the power output (wattage) is above that required by your machine.
__________________
Richard

If in doubt RTFM
richardhula is offline   Reply With Quote
Old 15-04-2011, 02:25   #6
cruiser

Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
Re: Running a laptop without an inverter

Quote:
Originally Posted by richardhula View Post
DC is DC yes but your laptop will require a specific voltage usually above the nominal 12 volts available on your boat.
Yep, mine is 19v which works fine with a dc to dc 150w supply for cars from maplins. Fully discharged and running it pulls just over 4a dc/dc instead of over 7a with the ac supply through an invertor.

re the OP I was wondering how a laptop would know that its' power was coming from a dc to dc supply and not an ac to dc supply plugged into the wall. Which is not to say that it doesn't know, some maunufactures may not like the thought of you to be buying cheap power supplies from generic makes instead of their expensive own brand items......

Imagine!

But google often comes up with ways around such control, red rag to a bull for many people.
conachair is offline   Reply With Quote
Old 15-04-2011, 02:34   #7
Registered User
 
richardhula's Avatar

Join Date: Nov 2008
Location: UK
Boat: S M Hudson 60' narrowboat
Posts: 347
Send a message via Skype™ to richardhula
Re: Running a laptop without an inverter

Quote:
Originally Posted by conachair View Post
re the OP I was wondering how a laptop would know that its' power was coming from a dc to dc supply and not an ac to dc supply plugged into the wall. Which is not to say that it doesn't know, some maunufactures may not like the thought of you to be buying cheap power supplies from generic makes instead of their expensive own brand items......
I think he was referring to the fact that his latest laptop wouldn't run on straight 12 volts unlike his previous.
__________________
Richard

If in doubt RTFM
richardhula is offline   Reply With Quote
Old 15-04-2011, 02:45   #8
cruiser

Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
Re: Running a laptop without an inverter

Quote:
Originally Posted by richardhula View Post
I think he was referring to the fact that his latest laptop wouldn't run on straight 12 volts unlike his previous.
Don't think so...

Quote:
My previous laptop would run quite fine from a standard 12V DC cigarette-lighter type outlet using a DC-DC adaper, with adjustable output, so I would just set it to the required voltage (16V, from memory) and off we'd go.
conachair is offline   Reply With Quote
Old 15-04-2011, 03:50   #9
Registered User

Join Date: Sep 2010
Posts: 793
Re: Running a laptop without an inverter

You could try an iGo adapter. There are modes that run off DC and have different plug tips for different laptops, so others can use it too. I've had good luck with them over the years. I think they are widely available at Radio Shack in the US.
twistedtree is offline   Reply With Quote
Old 15-04-2011, 05:16   #10
Registered User
 
richardhula's Avatar

Join Date: Nov 2008
Location: UK
Boat: S M Hudson 60' narrowboat
Posts: 347
Send a message via Skype™ to richardhula
Re: Running a laptop without an inverter

Quote:
Originally Posted by conachair View Post
Don't think so...
Mis-read apologies
__________________
Richard

If in doubt RTFM
richardhula is offline   Reply With Quote
Old 15-04-2011, 05:58   #11
Registered User

Join Date: Dec 2009
Posts: 2,959
Images: 4
Re: Running a laptop without an inverter

Inverters are not big power wasters. Get a reputable brand. Get one just a little larger than you need, but not much larger, as mentioned above. I use a 300W inverter for my laptop battery charging of 100W. Cheaper inverters may interfere badly with VHF, AIS and SSB. Also cheaper ones tend to be less efficient.

The laptop does it's own conversions inside as the brains run on 1.2V or 3.5V or whatever. All done with DC-DC converters. It's the way the world's electronics work.
daddle is offline   Reply With Quote
Old 16-04-2011, 16:38   #12
Registered User

Join Date: Apr 2011
Location: MEDITERRANEAN
Boat: MAXUM 4600 SCB 46FT
Posts: 2
According to my knowledge from 12 V DC u can feed lesser voltages suc as 9 V etc through electronic circuit. It is available in market, however for greater voltages such as 16 V u need AC therefore inverter i(which convert dc to ac for converting higher voltages) is a must. Both options waste similar energy through heat loss. For inverter option due to electronic conversion of AC the output is not pure sinus wave which i do not like this part, however it works.
Good luck and Regards
Filipo is offline   Reply With Quote
Old 16-04-2011, 17:59   #13
Registered User

Join Date: Sep 2010
Posts: 793
Re: Running a Laptop Without an Inverter

DC to DC converters can be used to step up the voltage or step down the voltage, so you can go from 12V up to 16V, or down to 9V as examples. Both are based on high frequency switching and a variety of electronic magic. Although there are AC-like intermediate voltages that occur internal the a DC-DC converter, calling it an Inverter would be a misnomer. A good DC-DC converter will be in the 85% to 95% efficiency range.

An Inverter is DC to AC, where the AC output is some approximation of a standard AC wave form (sine wave) at some standard voltage and frequency. Lots of effort goes into the design to make the waveform better match the native AC sine wave form. Inverters run in the 85%-95% effeciency range as well.

Using an inverter to create AC, then plugging in a laptop charger to run your computer is simple and easy, and for intermittent use makes perfect sense. The only real downside is that you are running two converters back to back, so their losses compound. If you are running a laptop all the time, using a DC-DC converter like an iGo or other brand will be more efficient. Whether the difference matters depends on your other loads and whether the laptop is significant, and hence whether the savings makes an overall meaningful difference. On a sail boat, it could really matter. On a power boat, it's probably insignificant.
twistedtree is offline   Reply With Quote
Old 16-04-2011, 18:55   #14
Registered User
 
HappySeagull's Avatar

Join Date: Dec 2010
Location: B.C.,Canada
Boat: 29'
Posts: 2,423
Re: Running a Laptop Without an Inverter

Quote:
Originally Posted by Weyalan View Post
Given the power losses with converting DC to AC and then the losses with converting it right back to DC again, I have never been a big fan of using an inverter to run a laptop.

My previous laptop would run quite fine from a standard 12V DC cigarette-lighter type outlet using a DC-DC adaper, with adjustable output, so I would just set it to the required voltage (16V, from memory) and off we'd go.

My new laptop, apparently, has some sensor in the power inlet and won't allow me to do this. So at this stage a small (150W) inverter looks like the only solution...

Any alternatives?
Weyalan...is it a DELL? I know many of these have a third wire at the dc jack...Perhaps other makes do too,nowadays.They can likely be tricked but....
HappySeagull is offline   Reply With Quote
Old 16-04-2011, 22:10   #15
Registered User
 
senormechanico's Avatar

Join Date: Aug 2003
Boat: Dragonfly 1000 trimaran
Posts: 7,145
Re: Running a Laptop Without an Inverter

I have several laptops in the house (my systems administrator son supplies me with old stuff from his work when they upgrade).
I have had great luck with this Acer laptop on the boat. I'm writing this post from an Acer 3100. It's decently fast and relatively easy on the DC. It has no problems running on a 12 volt socket and it even charges its own battery at the same time.
__________________
The question is not, "Who will let me?"
The question is,"Who is going to stop me?"


Ayn Rand
senormechanico is offline   Reply With Quote
Reply

Tags
inverter, laptop

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Inverter Running Despite Absence of Load hummingway Electrical: Batteries, Generators & Solar 16 10-11-2010 09:43
Calculating Amps Drawn Before Inverter and After Inverter ? impi Electrical: Batteries, Generators & Solar 23 26-09-2010 22:24
Running a Laptop Efficiently dennisail Marine Electronics 24 25-05-2010 09:08
asus laptop running seaclear scotty Navigation 7 16-10-2008 09:16
Running a laptop from 12 volt supply Dunkers Navigation 12 09-08-2006 10:19

Advertise Here


All times are GMT -7. The time now is 04:17.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.