Conduit Body as a Pull box ... not possible

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lakee911

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Columbus, OH
Suppose I was running 3#2,1#4G (XHHW), 2"C (PVC) and I need a pull box.

An obvious choice would be a type "C" conduit body. According to NEC 314.28(A)(1), the conduit body can be no less than 8x the largest raceway and I'm allowed to use the minimum size of the raceway that would be required. So, fortunately for this size wire I'm allowed to use a minimum size of 1-1/4"C.

So, 8*1-1/2" = 10"

This conduit body, according to literature is only approx. 8" long, so it can not be used!

Now, what I think is stupid is if I splice my wire, according to NEC 314.28(A)(1), I am allowed to use 6x (rather than 8), so I'm down to 7-1/2", so this would be allowed.

I don't want to splice it though, and I'm not sure that a PVC box exists that would be like 2" or 3" wide by 10" long (or 16 for that matter if it had to be full sized).

I don't get it... Can anyone offer insight?
 
Have you looked into using a 2-1/2" C condulet?

Also you might want to look at the listing of the 2" condulet and see what the maximum listed amount and size of conductors the conduit body is listed for. (See 314.28(A)(3))

Chris
 
lakee911 said:
Now, what I think is stupid is if I splice my wire, according to NEC 314.28(A)(1), I am allowed to use 6x (rather than 8), so I'm down to 7-1/2", so this would be allowed.
Click to expand...

To add what Chris has said, the condulet needs to list the volume for splices and for conductors larger than 6 awg table 314.16B can't be used. Therefore splices are not allowed in condulets with conductors larger than 6 awg.
 
The only thing I can figure is that they must think it's easier to get that loop of wire in the box or condulet if you are making a change in direction rather than going straight .


... if you were splicing there would be no loop to stuff into the box....
 
In case anyone is interested in the history of condulets/conduit-bodies, I found an interesting link: http://www.crouse-hinds.com/condulet100/100_years_history.cfm

NEC 314.28(A)(3) said:
"Boxes or conduit bodies of dimensions less than those required in 314.28(A)(1) and (A)(2) shall be permitted for installations of combinations of conductors that are less than the maximum conduit or tubing fill (of conduits or tubing being used) permitted by Table 1 of Chapter 9, provided the box or conduit body has been listed for, and is permanently marked with, the maximum number and maximum size of conductors permitted."
Click to expand...

So, Cantex has a PDF showing the technical information for their type C conduit bodies. Their 2" box is too small for my application. I do not know if the conduit body itself is "marked with the number and maximum size of the conductors permitted" but their PDF shows that it is good for 3#4/0 conductors. I'm sure it meets Table 1 as well.

Anyways, I'm not sure if NEC 314.28(A)(3) alleviates me from not having that length required as a pullbox or if it just allows me to pass the wires through them. What do you think?

a 12x12x4 JB starts to get pretty pricey (compared to a conduit body) and takes up a lot of room here.

A 2-1/2 conduit body (according to that PDF) will work but it's HUGE and relatively speaking much more than the 2 incher!
 
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lakee911 said:
Now, what I think is stupid is if I splice my wire, according to NEC 314.28(A)(1), I am allowed to use 6x (rather than 8), so I'm down to 7-1/2", so this would be allowed.

I don't want to splice it though, and I'm not sure that a PVC box exists that would be like 2" or 3" wide by 10" long (or 16 for that matter if it had to be full sized).

I don't get it... Can anyone offer insight?
Click to expand...

If you want to splice conductors in a conduit body you should reference 314.16(C)(2)
 
Then look into Chris's answer (#2 post) to get the room the code requires. How about a Mogul condulet? They are bigger but at my local supply house also a s/o. Or splice in the condulet (yuck) .
 
Pierre C Belarge said:
If you want to splice conductors in a conduit body you should reference 314.16(C)(2)
Click to expand...

I don't want to splice (see what you quoted from me) and 314.16 states "... Boxes and conduit bodies enclosing conductors 4 AWG or larger shall also comply with the provisions of 314.28," which is what I was referencing.

Johnmcca said:
Then look into Chris's answer (#2 post) to get the room the code requires. How about a Mogul condulet? They are bigger but at my local supply house also a s/o. Or splice in the condulet (yuck) .
Click to expand...

No splicing going to happen. I'm going to look into this Mogul business. Maybe it's available in PVC and C type. Thanks.
 
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Your conduit is 2", you are pulling 3- #2 and 1-#4 right? The "C" fitting is rated for 3 # 4/0 which is I think more cubic inch takeup than 3 #2 and a #4 thhn will consume. As far as how hard? Well I did one this week with 2" emt and 3- 3/0 no equip ground (for a service drop, and would have been more than 360 if the C wasn't used) and it was tough to go out and back in the C, but not so bad , I gotter done. All megger ok too cap'n. They used to sell conduit bodies with rollers built into them, not the pvc ones, the metal and it was sweet. Haven't seen any for a long while, do they still make them?
 
lakee911 said:
a 12x12x4 JB starts to get pretty pricey (compared to a conduit body) and takes up a lot of room here.
Click to expand...


You sure it needs to be 12 X 12 X 4? couldn't it be shaped pretty much like the C only a little bigger.

There was a few months back a big thread about what you are talking about... there were some pictures on there showing boxes maybe 4 x 4 x 12 or so... like a trough.
 
lakee911 said:
a 12x12x4 JB starts to get pretty pricey (compared to a conduit body) and takes up a lot of room here.
Click to expand...

realolman said:
You sure it needs to be 12 X 12 X 4? couldn't it be shaped pretty much like the C only a little bigger.

There was a few months back a big thread about what you are talking about... there were some pictures on there showing boxes maybe 4 x 4 x 12 or so... like a trough.
Click to expand...

Exactly, forget the 12 x 12, in this case 4 x 4 trough 12" or more long would work great.

I use 6 x 6 trough as pull points on 4".
 
So, I took a look at a Carlon 2" type "LB" conduit body and inside it says:

UL PVC CSA
CARLON
63 CU IN VOL
2" 3 WIRE FILL MAX WIRE SIZE
E983 STR. THROUGH AWG - 2/0
SIDE EXIT AWG - 1
E984 - E985 - AWG 4/0
E986 AWG - 3/0
E987 AWG - 2/0
Click to expand...

So, I guess NEC 314.28(A)(3) it is! Thanks for the help from everyone.
 
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