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#112535 - 07/07/01 07:51 PM No lb's please!
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There is nothing wrong here, I hope. I thought that the wireway would look better than 20 LB's. Also, it turned out to be a lot easier to install since I didn't have to be real meticulous about the hole location in the sheeting. Largest raceway is 1" & the largest conductor is #6thhn.

Tom

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#112536 - 07/08/01 05:37 AM Re: No lb's please!
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Looks like there might be a violation of the 30 conductor in a cross-section rule? (I don't have my book today).

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#112537 - 07/08/01 06:00 AM Re: No lb's please!
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electure;
very interesting observation, 362-5. does "any cross section" imply the total # of wires in the troffer, or simply those that would cross each other , i.e.-i can hold 30 with one hand?

I do not understand the main rule as applied to the EX, and the derating. do it, don't do it???

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#112538 - 07/08/01 11:09 AM Re: No lb's please!
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The "cross section" would be the 4"x4" dimension & would not include the 5' dimension, otherwise, that would be a leangthwise section. Confused? See the second paragraph of 362-5 where it speaks about the cross sectional area of conductors, nothing is said about measuring their areas leangthwise.

If the conductors did a bunch of cross overs, then you could derate them, use as many as you want provided you don't fill up any cross section more than 20%. Derating penalty would be a killer though.

This installation prompted a question that I never received a good answer to. This is labeled as a wireway & I have to use the rules of a wireway. If I had a custom made junction box, I would be able to fit in 426 #12's & no derating. ((4x4x60")/2.25=462)
Is there any differance, other than technical definitions?
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#112539 - 07/08/01 12:03 PM Re: No lb's please!
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that's it!, i'm going to hide under my bed.....hold my calls......

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#112540 - 07/08/01 03:08 PM Re: No lb's please!
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Your question would have to be answered by having a NRTL sign your 4-4-60 off as a j/b.
I routinely see this section of the code violated, & any reference to this section usually brings a "Huh?" from the one installing the wireway.

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#112541 - 07/09/01 03:12 PM Re: No lb's please!
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As far as I know, the only listing requirement for boxes applies to damp & wet locations. If you need to make a custom size box, all you have to do is meet 370-40. I've seen plenty of custom made boxes over the years & there isn't a thing wrong with them. The key , of course, is the box acceptable to the AHJ?


Of course, I've seen a few wireways that you couldn't get the covers on because of the wire inside. Sawmills around here are notorious for this.

Tom

[This message has been edited by Tom (edited 07-09-2001).]
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#112542 - 07/09/01 03:15 PM Re: No lb's please!
Tom Offline
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Registered: 01/01/01
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Loc: Shinnston, WV USA
A

[This message has been edited by Tom (edited 07-09-2001).]
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