Seeking: Conduit pulling advice from experience.

K

knoll

Member
Location
washington state
Occupation
apprentice
Hi All, I'm new here, lurked for a long time. I'm wondering if this pull seems doable to folks.

I've got four conductors total.
Three 250kcmil XHHW alu and One #2 XHHW alu that need to go through 2" sch40 conduit. Using the tables in chapter 9 I'm under the 40% fill (barely, like 39%). Online calculators (southwire) are more optimistic and say 33%. So I should be good conduit fill wise. I've got two 45s in the pull.

As far as pulling goes, I'm worried. I would typically just size up the PVC. But it's already underground. Anyway one done this? Will the pull be doable?

(I know my other options are downsizing the circuit and using 4/0 or putting in new conduit)

Thanks!
 
I have pulled many runs at or even a bit over the 40% fill. As Larry said, a good feed and completely cover the conductors with the wire pulling lube. Even a small "dry spot" on the conductors can make a difference.
 
knoll said:
've got four conductors total.
Three 250kcmil XHHW alu and One #2 XHHW alu that need to go through 2" sch40 conduit. Using the tables in chapter 9 I'm under the 40% fill (barely, like 39%). Online calculators (southwire) are more optimistic and say 33%. So I should be good conduit fill wise. I've got two 45s in the pull.
Click to expand...
Shouldn't be a problem with only 2-45's in the run. The most important thing is how well you make the pulling head.
 
Thanks for the replies everyone, good to know I'm not totally insane for trying it. I'm definitely planning on lots of lube and a well made pulling head. I'll probably be the one feeding, somehow it's always harder to get people to feed well and communicate while doing it. :p
 
electrofelon said:
I don't think it will be bad
That said, is this single phase? If so I would use a 2 size reduced neuter.
Click to expand...
It is single phase, residential. Going from a meter w/distribution to house panel. You'd go down to 3/0 for the neutral? I'm still trying to wrap my head around neutral sizing. That would help a bit with the pull.
 
electrofelon said:
I don't think it will be bad
That said, is this single phase? If so I would use a 2 size reduced neuter.
Click to expand...
I think that was in the code at one time, but now you need to do the neutral load calculation. If the load calculation would support it, and it might, the minimum size neutral that the code would permit for this service would be 1/0 aluminum.
 
don_resqcapt19 said:
I think that was in the code at one time, but now you need to do the neutral load calculation. If the load calculation would support it, and it might, the minimum size neutral that the code would permit for this service would be 1/0 aluminum.
Click to expand...
97% of the time I use plexed USE/rhh-2 for residential services which pretty much always have a 2 size reduced neutral. I have never been asked for a neutral size load calc, or calcs in general for that matter for residential.

Just as a side note: the USE has thicker insulation than XHHW and makes a surprisingly large difference in conduit fill.
 
I pulled 250 Pratt (250-250-3/0 USE) in 2" about 750 feet. That fill is nearly the same as yours. It had just 1 90 which I fed into, and some long gradual bends. It wasn't bad at all. The difference is the jamming risk was high but since the conductors were plexed, that mostly eliminated the risk. You don't have much risk of jamming.
 
You must log in or register to reply here.
Top