On 26 Jan 2006 at 18:22, Stephan Prince wrote:

> We are trying to implement a Point of Sale system for retail sales at
> remote location. There is no A/C power to speak of, but a generator that
> charges a bank of deep charge, gel 12volt batteries. We want to run a
> couple of notebooks or laptops for sales directly of the bank of batteries
> rather than invert the D/C to A/C. This loses so much in the invertion
> process that it is inefficient. I know you can run laptops off external
> powersources, but how can I regulate the power off the bank of deep cells
> to match these laptops? Thanks for all your help,
> 

I'm looking at my 12V car cigar lighter socket adaptor for my laptop.  
Here are some details:

Make:	VANSON
Model:	SDR-70W
INPUT:	DC 11 to 14 Volts
OUTPUT:	DC 15/16/18/19/20v  3.5amp max

It works very well, with accurate output voltages.

There are probably other makes and models.  Make sure to check that the 
maximum output current is sufficient to power the particular laptop.  That 
figure should be printed on the mains adaptor for the laptop.

I bought mine over the internet, but I'm afraid I can't rememer where now. 
 They should be easy enough to find.  I expect you will need one per 
laptop.

Good luck,

Neil Taylor

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