Wire Way Fill

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GSXR600

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Hey guys just want to make sure i am doing this wire way fill correctly...

I have the following in it.

12- 4/0 THHN
4- #3

12 x .3237= 3.8844
4 x .0973= .3892
4.2736 / .20= 21.368 in. 2

which means i would need a 6" x 6" trough.

Now what i ahve is a MDP that is feeding a few panel in an electric room and the trough is running above all panel and i am going to nipple up to the trougn from each panel. Now the distance from where the conduit enters the trough to the opposing wall is determined from 312.6a which would be 4" right seem strange that they allow us to use the one terminal row when i have 4 wires leaving each conduit...
 
GSXR600 said:
Hey guys just want to make sure i am doing this wire way fill correctly...

I have the following in it.

12- 4/0 THHN
4- #3

12 x .3237= 3.8844
4 x .0973= .3892
4.2736 / .20= 21.368 in. 2

which means i would need a 6" x 6" trough.
Click to expand...

Looks good.

Now what i ahve is a MDP that is feeding a few panel in an electric room and the trough is running above all panel and i am going to nipple up to the trougn from each panel. Now the distance from where the conduit enters the trough to the opposing wall is determined from 312.6a which would be 4" right seem strange that they allow us to use the one terminal row when i have 4 wires leaving each conduit...
Click to expand...

Your description makes it sound like there are no splices in the wireway. If that is the case the distance between conduit entries would be determined as per 314.28(A)(1) and (2).
 
GSXR600 said:
Hey guys just want to make sure i am doing this wire way fill correctly...

I have the following in it.

12- 4/0 THHN
4- #3

12 x .3237= 3.8844
4 x .0973= .3892
4.2736 / .20= 21.368 in. 2

which means i would need a 6" x 6" trough.

Now what i ahve is a MDP that is feeding a few panel in an electric room and the trough is running above all panel and i am going to nipple up to the trougn from each panel. Now the distance from where the conduit enters the trough to the opposing wall is determined from 312.6a which would be 4" right seem strange that they allow us to use the one terminal row when i have 4 wires leaving each conduit...
Click to expand...

If you use "√(Total area of conductors ? 20% fill) = minimum wireway size"
√(4.2736/.20) = 4.62" thus 6" x 6" wireway

Why is it you dont have to derate until you get to 30 ccc and in conduit you have to start derating at 4 ccc?
 
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GSXR600 said:
the trough is running above all panel and i am going to nipple up to the trougn from each panel. Now the distance from where the conduit enters the trough to the opposing wall is determined from 312.6a which would be 4" right seem strange that they allow us to use the one terminal row when i have 4 wires leaving each conduit...
Click to expand...

The table 312.6a can be used for minimum if the gutter for the terminal is adjacent to another gutter that has a dimension of table 312.6b.(7") If not 312.6b is used.(7") See exception # 1 312.6b2.

Rick
 
I was reading over article 312.6 (B)(2)(2)Ex 1 which in part states:

"....provided the conductor enters or leaves the enclosure where the gutter joins an adjacent gutter that has a width that conforms to Table 312.6(B) for the conductor."
Should it not read: "....provided the conductor enters or leaves the enclosure where the enclosure joins an adjacent gutter that has a width that conforms to Table 312.6(B) for the conductor." Any thoughts on this?
 
Augie???

doesnt 312.6A allow you to use table 312.6A for the width gsxr600 is referring to. So gsxr600 would need a min. of 8" x 8" trough??

Edited: now 376.23 b allows you to get away with 1 wire per terminal which would be 4"
 
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The code isn't hard to follow is it.
icon12.gif
. In the Op's run, the minimum wireway dimension for bending radius of 4/0 is 4", but 6" is needed for conductor fill. To meet the requirements of 312.6(B)2 exception # 1, a 7" wireway is needed if the wall opposite to the terminal inside the panel is less than 7". If the dimension inside the panel meets the 7" requirement, the wireway can be the required for conductor fill and bending radius.

Rick
 
ruwired,
i dont believe that article has anything to do with GSXR600 installation. 376.23 (a) states what table and what column should be used... So you could get away with a 4 x 4 if the fill wasnt so high...
 
Aux. Gutter or Wireway or Pullbox

Aux. Gutter or Wireway or Pullbox

Question here.....
What makes a wireway a wireway and not a aux. gutter or pull box?
If I have 4 like panels with a 12"x12"X15' long box/trough/gutter mounted on top with 24" long emt nipples between the panel and trough; with my branch ckt. conduits going out the top or back of the trough/box/gutter with no splices, does that now make it a pull-box and not a wireway.

The reason for the question is to find out if I have to adhere to the 30 ccc rule in NEC for aux.gutters or not. I would like to pull #10 and not #8 home runs if at all possible. But I want to cover my ground before I bring this up with the inspector. His nickname is turn'em down Downs.

My comprehension on this topic after reading other threads on similar issues would be that it is not a gutter if longer than 30' it is a wireway, and if there are no splices in the trough than per code it is a pull box.

Any help would be appreciated.
 
shaw0486 said:
ruwired,
i dont believe that article has anything to do with GSXR600 installation. 376.23 (a) states what table and what column should be used... So you could get away with a 4 x 4 if the fill wasnt so high...
Click to expand...

Shaw you brought up the 376.23 article.
Article 376.23 does needs to be considered when sizing a wireway above/below a panel, but not when looking for the minimum dimension for opposite wall to terminal size which is what the OP was asking about. In my last post i was pointing out the three different size wireways that would factor in using the 4/0 conductors. Most likely the opposite wall dimension has already been met with a new panel board installation..

Rick
 
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