Dirran wrote:Remember vehicles are DC current which means the longer the wire, the heavier the gauge required as DC current tapers off over distance, and yes a few feet will make a difference.
E=IR for all "flavors" of electricity (AC/DC). Meaning for the same current through the same wire will experience the same voltage loss/drop with AC or DC electricty. 120 AC volt eleltricity can transport 10 times the power as DC 12 volt current when the current is the same . P(power)=V(volts) X I(current).
The reason it is more critical to use an appropriate wire size with dc is that if you lose 3 or 4 volts (of the 12 volts you start with) in the wire, the thingy (load) you're trying to power will notice it as it's only getting 66-75% (8-9 volts) of the voltage it needs. If you are using 120 volts and lose 3 or 4 volts your thingy (or load) is getting 97% (116 volts) and since 120 volts varies a bit (110-120 volts) your ac load probably won't even notice the difference.
I know this is quibbling, bickering, bun fighting just a bit but I think it helps to understand things so you know what effect your choices will make.
The best way to check if your wiring is adequete is to check the voltage right at the load with the load running/turned on and see what voltage your getting after the loss in your wiring.
Here is an interesting site that discusses acceptable voltage drops:
http://www.solar4power.com/solar-power-volt_drop.html
Cheers,
Gus
The opinions in this post are my own. My comments are directed to those that might like an alternative approach to those already espoused.There is the right way,the wrong way,the USMC way, your way, my way, and the highway.
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