>
>, we can operate them directly from the
>12V supply without loss due to an inverter, and they take up less room.
>Henry Davis Consulting, Inc / new product consulting
>PO Box 1270 / product readiness reviews
>
>Henry I have just gotten a CXT laptop and I would like to run it off of the
>12 volt system. Do I need to buy a special adapter or can I just run it
off
>of the inverter. Seem like a lot of extra wires and stepping up just to
>step back down. What is your advice?
>Thank You
>
Our laptops can plug into a cigarette lighter socket. The internal power
supply regulates the 12V to the required internal voltages. So, there is no
need to use the inverter to power the AC power supply. There are several
companies that make 12V adapters to replace the 120V AC to 12V DC converter
that some laptops use. Your computer retailer likely has these or can order
them. If you can't find an adapter for your notebook let me know and I'll
look through my files for companies that you can contact directly.
CAUTION: some notebook computers will ONLY charge and run from 120V AC -
like the Toshiba CDT series. Be certain to read the input voltage on the
notebook itself. Most will have a plug in cord that fits a round socket. You
may find the voltage printed on the computer case. If it says 9V or
something less do not use a straight adapter to your 12V system as it will
likely cause damage.
Many notebook PCs have accessories to permit you to use the 12V system.
If you must operate your notebook from 120V AC due to its design (like the
TOshiba) you really don't have a choice but to use the inverter. I also have
a TOshiba so I use a small inverter just to power the notebook when I need
it. The modified sine wave inverter doesn't seem to affect the Toshiba, but
I can't be certain of other similar designs.
The main reason to use the 12V directly if you can is that is it
significantly more effecient. That's a big consideration for us because we
often boondock. TO give you an idea of the energy efficiency difference, one
inverter that I have is 85% efficient. The AC to DC converter is a linear
power supply that is about 60% efficient. All told, the combination means
that I would draw 20 amps instead of 10 for one of my configurations.
Henry
Henry Davis Consulting, Inc / new product consulting
PO Box 1270 / product readiness reviews
Soquel, Ca 95073 / IP reviews
ph: (408) 462-5199 / full service marketing
fax: (408) 462-5198
http://www.henry-davis.com
