Conduit size ground wire

[designer82]

So when sizing a conduit... let's say I have 3 current carrying conductors and the table says a 2" conduit fits 3#300.

What about the ground wire? Is it still ok on the 2" or should it be upsized to 2.5" to handle the ground wire?

Thanks

 

[david luchini]

So when sizing a conduit... let's say I have 3 current carrying conductors and the table says a 2" conduit fits 3#300.

What about the ground wire? Is it still ok on the 2" or should it be upsized to 2.5" to handle the ground wire?

Thanks

The conduit must be sized for all of the conductors in the raceway, including the ground wire.

 

[winnie]

As David says, the ground wire counts for conduit fill.

Since the ground wire is often smaller than the circuit conductors, you often need to calculate the actual conduit fill using actual conductor sizes rather than using the tables.

3 Al 300 kcmil THHN + 1 AL #4 THHN fits in a 2" EMT. (But Cu THHN doesn't, because Al is generally compact stranded and Cu is generally not.)

You also say '3 current carrying conductors'. You must count _all_ conductors for conduit fill, including the neutral that doesn't count for derating.

-Jon

 

[infinity]

I agree with the others. I always tell my apprentice to remeber if it fills the raceway it counts towards raceway fill. They seem to get confused when they start thinking about CCC's and only counting 1 EGC in a box, etc.