Unraveling the Mystery of Copper Resistance Values in AWG

AI Thread Summary
The discussion focuses on the calculation of copper resistance values for #6 AWG wire, where the user initially miscalculated the resistance due to using the radius instead of the diameter in their formula. The correct diameter of #6 AWG is 4.115 mm, which led to confusion in determining the resistance value. The user acknowledges the mistake after receiving clarification, realizing that this oversight significantly affected their calculations. This exchange highlights the importance of precise measurements in electrical calculations. Accurate understanding of wire specifications is crucial for determining resistance values.
satchmo05
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Hey all,

I am looking at the American Wire Gauge chart listed on Wiki ([PLAIN]http://en.wikipedia.org/wiki/American_wire_gauge).[/PLAIN] I am attempting to determine how they are getting their copper resistance values.

From my education, DC resistance is equal to [length/(conductivity*pi*radius of wire2)]. For example, if I am using #6 AWG - radius is equal to 4.115[mm], conductivity of copper is equal to 5.96e7[S/m]. This gives me 0.3154[mOhm/m], nearly four times smaller than the accepted value of 1.3[mOhm/m].

Where am I going wrong? Thanks,

- Satchmo05
 
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Oh wow, that's embarrassing. Thanks for the second set of eyes. I've been staring at that very simple equation for 20 minutes and I just couldn't get anywhere. Most appreciated.
 
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