Good rule of thumb

[alohaelectric81]

What is a good rule of thumb of the carrying capacity of aluminum

 

[hardworkingstiff]

What is a good rule of thumb of the carrying capacity of aluminum

I guess I don't get it. Is this a trick question?

My answer would be 310.16

 

[Minuteman]

The only "rule of thumb" I know is: For aluminum, size your conductors up one size larger than you would for copper.

 

[hillbilly]

How about..."Break out the torque wrench".

 

[charlie tuna]

aloha,
your question might be better explained by the rule of current carrying of copper--------------- one inch square copper bus is supposed to carry 1000 amps
one inch square aluminum bus is supposed to carry ??? amps?
you can find it in the code book on conductor properties in the back of the book....................

 

[jeff43222]

I believe I read somewhere that aluminum generally has about 55% of the conductivity of copper. So I think a good rule of thumb is that you need twice as much aluminum as copper for the same ampacity.

For example, when I install a 200A service, I have to use 2/0 copper or 4/0 aluminum.

 

[ralpha494]

366.23 says 700 amps per square inch for aux.gutters.

 

[infinity]

I believe I read somewhere that aluminum generally has about 55% of the conductivity of copper. So I think a good rule of thumb is that you need twice as much aluminum as copper for the same ampacity.

For example, when I install a 200A service, I have to use 2/0 copper or 4/0 aluminum.

Actually if copper had a conductivity of 1, aluminum would have a conductivity of .61 or 61% that of copper. However if you compare comparable sized conductor ampacities in 310.16 you'll see that the general rule is that aluminum has about an 80% ampacity of equivalent sized copper conductors.