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Old 05-27-11, 10:44 PM   #3
Xringer
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The major problem with using 12v is the losses make you end up spending a lot on bigger copper wiring.

A 400w Plasma HDTV 120vac runs 3.33 amps. A 12vdc HDTV running 400w needs 33.3 amps..

The losses I'm talking about is caused by resistance in the wiring.

Watts lost = Resistance x Amps squared.
33.3 squared= 1,111.11 which would be multiplied by the resistance in ohms.
So, if I had about 0.2 ohms resistance in the power cable, the cable would
be heating the room to the tune of 222.22 watts of heat..


If you think about it for a while, you will come to understand,
120vac / 240vac is a pretty efficient power delivery method.
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