Poignard
Well-Known Member
.
I can't remember where I bought mine, or what it cost, but I'm sure I wouldn't have spent so much on it.
How to power a laptop
- Thread starter Cheeky Girl
- Start date
I can't remember where I bought mine, or what it cost, but I'm sure I wouldn't have spent so much on it.
trbt
Active Member
That is a nice setup, that can put 55Wh into the laptop and only takes 5.5Wh from the boat battery to do so
But beware cheap chinese "car laptop chargers", I once took one apart and found it had 2 separate circuit boards. One for a 12V -> 230V inverter and another for a 230V laptop power supply. Apparently some brilliant mind took two separate products and simply combined them into a new case to create a new product...
pvb
Well-Known Member
That is a nice setup, that can put 55Wh into the laptop and only takes 5.5Wh from the boat battery to do so
His post was very badly worded, and you could be forgiven for thinking that's what he meant. I think he was actually trying to show that there's not much difference between using inverters with either 85% or 95% efficiency.
Refueler
Well-Known Member
For years I have been powering various laptops DIRECT of the 12V ... I just avoid having it plugged in when starting / stopping engine.
I can hear you all now .... but my Dell needs 18V .... my Thinkpad needs 16V ... etc. etc .....
That's because it will be charging the battery as well .... the boards inside that actually do the work are either 5V or 3V ... so all that power is reduced for the boards ...
The limitation with my way - is when you start to plug in items that take power from the computer .... then the 12V direct can struggle ....
Depending on the workload - the computer may also supplement power from the battery - so after a while will shut down.
But for simple plotting with a GPS ... 12V direct is usually enough ....
I have a couple of the older Thinkpad 600E's (they like 16V) ... I run those without batterys in ... and they do fine.
As another says - best to avoid inverters .. why up the voltage just to step it back down again ... incurring losses all the way ... if you really need an adaptor - get a DC - DC job .... but make sure its up to the job ... try to get a reasonable extra watts over the minimum required ...
I can hear you all now .... but my Dell needs 18V .... my Thinkpad needs 16V ... etc. etc .....
That's because it will be charging the battery as well .... the boards inside that actually do the work are either 5V or 3V ... so all that power is reduced for the boards ...
The limitation with my way - is when you start to plug in items that take power from the computer .... then the 12V direct can struggle ....
Depending on the workload - the computer may also supplement power from the battery - so after a while will shut down.
But for simple plotting with a GPS ... 12V direct is usually enough ....
I have a couple of the older Thinkpad 600E's (they like 16V) ... I run those without batterys in ... and they do fine.
As another says - best to avoid inverters .. why up the voltage just to step it back down again ... incurring losses all the way ... if you really need an adaptor - get a DC - DC job .... but make sure its up to the job ... try to get a reasonable extra watts over the minimum required ...
trbt
Active Member
AngusMcDoon
Well-Known Member
Some lateral thinking which may help reduce if not solve the problem: get a laptop with lower power requirements. Look for solid state drive, smaller screen, passive cooling, switchable keyboard backlight, lower powered processor. Use flight mode unless you need connections. Disable unused hardware in device manager like the camera and wired ethernet adaptor, fingerprint reader etc. Pull out USB devices unless absolutely necessary. The Acer Swift 1 with a N5000 processor is a good contender. 12 hours per charge is possible with reduced screen brightness.
greeny
Well-Known Member
Yes , people like to overthink, over engineer and then over argue the benefits of their over costly solutions. We need to let them develop their sledgehammers to crack walnuts so we can best utilise our time in lockdown pulling their proposals apart.This is a completely innapropriate reply. It is far too simple and does not involve nearly enough arguing. I have had no choice but to report you to the forum mods.
Laser310
Well-Known Member
That dell 12 volt cigarette charger i posted above puts out 19 volts, according to the specs.
LadyInBed
Well-Known Member
Yes, but they were also running Win 95
But you are right, it would be worth a try to take the battery out and try it direct off boat battery as there is nothing to lose.
Refueler
Well-Known Member
The point I make is that the 'charger' you plug in does two jobs ... the BIGGEST being to charge the battery ...
Near ALL Notebook PC's (Laptops as many call them) can run of 12V direct.
I have Lenovo, Acer, Dell, ASUS, IBM, Siemens, ...... running 95 ... 98 ... 7, 8 and 10 ..... they all sit on 12V and work.
Why so many ? I keep the machines that get replaced in my companys. I use them for running Lasers, 3D printer, Chart Plotting ... literally any job at home etc. Saves my main machine for my job then.
Near ALL Notebook PC's (Laptops as many call them) can run of 12V direct.
I have Lenovo, Acer, Dell, ASUS, IBM, Siemens, ...... running 95 ... 98 ... 7, 8 and 10 ..... they all sit on 12V and work.
Why so many ? I keep the machines that get replaced in my companys. I use them for running Lasers, 3D printer, Chart Plotting ... literally any job at home etc. Saves my main machine for my job then.
black mercury
Well-Known Member
I have a 300 watt inverter and an older (10 year old) dell laptop. I took a real world amp reading between the battery and inverter with the laptop powered up. The meter was reading 7 amps.
