Sizing Wire Way

[GSXR600]

Ok I am a little confused with 376.23. I have a CT cabinet and Enclosed Circuit Breaker and i would like to lay an 8 x 8 wire way across the top to run (8) 350 Kcmill copper conductors. I am unsure if the code would consider this a U pull per 376.23 (b) which would make my cable entries be no less than 21" apart considering 3.5" conduit for the (8) THHN 350 and it would require the trough to also be at least 24.5" high. Is my understanding correct?

My other thought says that this is not a pull box senario and 376.23 (b) does not apply and that 376.23 (a) does and the i should be fine with a 5" clearance from the cable entry to the opposing side of the trough.

What are you thoughts?

 

[GSXR600]

now that i read 376.23 (b) again it does not state to go back to 314.28A1 and A2 for U pulls, just angle and straight pulls. I have a mike holt book that illustrates a violation on a trough with a u pull. I feel that the dimension showing Min 14 should be per 312.6A? Is this a mistake in the text book?

 

[Smart $]

Are the CT cabinet and breaker enclosure side by side? If so, why not just nipple out of CT cabinet side into side of breaker enclosure, and eliminate the wireway altogether?

 

[GSXR600]

that method is not allowed with the power company.

 

[augie47]

This could get interesting as opinions may vary.
Are your conductors being "laid in" as from your CT cabinet to adjacent enclosures or are they being pulled in from a conduit run ?

 

[GSXR600]

Augie,
They are being laid in the trough. Essentially I was considering connecting the ECB and CT cabinet together from both tops of the enclosures.

 

[Smart $]

that method is not allowed with the power company.

What POCO? I'd like to see if they publish their service requirements online. I know the POCO in my immediate area does not prohibit such.

FWIW, I agree with the MH graphic interpretation of the requirement... but have seen plenty of violations in my time.

 

[augie47]

IMO (and that of a few others here), the fact that the conductors are being laid in makes that an auxiliary gutter.
Not that the rules differ much between Art 376 and 366, but, to me, the keyboarding in both is "pulled through a wireway".
If you are "laying" the conductors, they are not being pulled through a wireway so 376.23 and 366.58 do not come into play.

Of course, the opinion that matters is the one YOUR AHJ has
(Few give much credibility to what some ole fart on the Forum tells you)

 

[GSXR600]

Here it is chief. Right out of BGE meter manual. We are coming out of the left bottom which would mean they limit you to come out the opposite end.

 

[GSXR600]

I have seen this done this way numerous times. I do not think this is what the NEC is indicating. The NEC doesnt even mention U pulls in 376.23(B) only straight and angle pulls.

 

[Smart $]

Here it is chief. Right out of BGE meter manual. We are coming out of the left bottom which would mean they limit you to come out the opposite end.

From what that shows, they require a minimum 12?12 "trough", and its connected directly to the enclosures. There are no interposing raceways, so 376.23 (b) does not apply.

 

[GSXR600]

uh 376.23 states "cable entries"??

 

[Smart $]

uh 376.23 states "cable entries"??

THHN is a conductor not a cable.

Also, if this is outdoors, shouldn't it be dual rated THWN, or THWN-2?

 

[Smart $]

376.23(A) applies, which takes you to what you suggested earlier, 312.6(A), one-wire-per-terminal dimension.

 

[GSXR600]

this is not outdoors all THHN that i have seen is dual rate THHN and THWN. Isnt that how it is in ohio?

 

[Smart $]

this is not outdoors

Okay.

all THHN that i have seen is dual rate THHN and THWN. Isnt that how it is in ohio?

Yep... just a habit of making sure.