#6 thhn wire

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iwire

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Massachusetts
I would also use Annex C but just to be clear Annex C is not part of the code and if it has a mistake (and I believe it has some) you can be in violation.

Best to do the math yourself to verify, plus I bet the 8 AWGs have a 10 AWG EGC.
 

OTT2

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Location
Orygun
I would also use Annex C but just to be clear Annex C is not part of the code and if it has a mistake (and I believe it has some) you can be in violation.

Best to do the math yourself to verify, plus I bet the 8 AWGs have a 10 AWG EGC.

Good point. Probably safer to use Chapter 9 Tables.
 

Little Bill

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Tennessee NEC:2017
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Semi-Retired Electrician
I would also use Annex C but just to be clear Annex C is not part of the code and if it has a mistake (and I believe it has some) you can be in violation.

Best to do the math yourself to verify, plus I bet the 8 AWGs have a 10 AWG EGC.

Where did 8 AWG enter into this?
 

Barndog

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Location
Spring Creek Pa
That tells me that someone else can put 4 sixes in 3/4".

Trust me, three is all you really want to have to pull in a 3/4".

I agree with you. We pulled three 6's and a 10 ground one time in a 3/4 emt. and it was a pain the whole way. I would personally go to 1" if i had to do it again.
 

K8MHZ

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Michigan. It's a beautiful peninsula, I've looked
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Electrician
I agree with you. We pulled three 6's and a 10 ground one time in a 3/4 emt. and it was a pain the whole way. I would personally go to 1" if i had to do it again.

I have a piece of 3/4" EMT I use in class. Three old (nasty, had been laying on the floor for years, if not decades) #6 conductors were pulled through it and energized with 480 three phase. After running a heater for about an hour an explosion occurred that sounded like a shotgun going off. A piece of one of the conductors had worked it's way to the conduit and blew about a 1/4 inch sized hole through it. I cut out that piece, conductors and all and kept it. You can see little molten copper balls inside the hole.
 

Strife

Senior Member
I agree with you. We pulled three 6's and a 10 ground one time in a 3/4 emt. and it was a pain the whole way. I would personally go to 1" if i had to do it again.

That's what you get for trying to use that old THW #6 you had stored in the warehouse for last 30 years.
Seriously, I pulled recently 200+' of 3#6 and a #8 with 3 90's and I kept having this feeling that the head came apart and I'm pulling only one wire.
 

K8MHZ

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Location
Michigan. It's a beautiful peninsula, I've looked
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Electrician
That's what you get for trying to use that old THW #6 you had stored in the warehouse for last 30 years.
Seriously, I pulled recently 200+' of 3#6 and a #8 with 3 90's and I kept having this feeling that the head came apart and I'm pulling only one wire.

It was the owner of the building's idea. He would trip over a stack of hundred dollar bills to pick a penny up off the floor.

When it was all said and done, he still ended up buying new wire. And paying a bunch extra in labor.

Did I mention that he was standing about 15 feet away when it blew? He jumped about a foot off the ground and probably had to buy new underwear, too.

I laughed about that for weeks.
 

hillbilly1

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North Georgia mountains
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Owner/electrical contractor
I havn't checked lately, but in a previous edition of the NEC, you could pull 4 #6 thhn in a 3/4" conduit, but could not pull 3 #6 and a #10 in a 3/4" conduit because of a different table you had to use. That being said, just pulled in 3 #6's and a #10 in four different 150' runs with about 260-300 degrees of bends in each run with no problem, even megged the runs per customer specifications. This is what was spec'd by the engineers, and passed by two different electrical inspectors in a tough jurisdiction.
 

infinity

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New Jersey
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I haven't checked lately, but in a previous edition of the NEC, you could pull 4 #6 thhn in a 3/4" conduit, but could not pull 3 #6 and a #10 in a 3/4" conduit because of a different table you had to use.

Something about this statement doesn't seem right, can you explain this?
 

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
I havn't checked lately, but in a previous edition of the NEC, you could pull 4 #6 thhn in a 3/4" conduit, but could not pull 3 #6 and a #10 in a 3/4" conduit because of a different table you had to use. That being said, just pulled in 3 #6's and a #10 in four different 150' runs with about 260-300 degrees of bends in each run with no problem, even megged the runs per customer specifications. This is what was spec'd by the engineers, and passed by two different electrical inspectors in a tough jurisdiction.

Something about this statement doesn't seem right, can you explain this?

This was way back in I can't remember the code cycle,(probably at least twenty years ago) but if you went by Table 9, the calculations would prohibit 3 #6 and one #10, but if you went by annex C, 4 #6 were allowed.
Just ran the calcs in the 2011 edition, and it will work now as it has for a while, but......since conduit area is now listed for individul types, 4 # 6 thhn will not fit in a 3/4" schedule 80 pvc or ENT (smurf pipe) and just barely under on schedule 40 pvc. It could have been a screw up in that old edition, as there have occasionally been a few over the years.
 
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