OK,... thought the distance in feet was supposed to go into the calculation.
I really had to look around to find something even close to caluclate R for steel...
Went to
http://www.electrician.com/articles/ampacity.htm and eventually wound up at
http://www.ibiblio.org/obp/electricCircuits/Ref/REF_3.html For the "Coefficients of Specific Resistance", since the only ref I had at work was the NEC. I couldn't find a formula to convert in2 to cmils. Peeved me, lemme tell ya...
Hey, it was late, I was bored... good brain workout anyway.
![[Linked Image]](https://www.electrical-contractor.net/ubb/biggrin.gif)
update - Just got home & got out my American Electrician's Handbook. Let's see...1/4" = 62,500 Cmils... steel R=81.179/cmil ft....
[This message has been edited by DougW (edited 04-16-2004).]