Why did this fail????????

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chevyx92 said:
What says we can't use it???
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What says we can't just make up our own way?

IMO the fact the UL listed LB is marked with limitations and the NEC does not tell us how to ignore those limitations we are behind the 8 ball.

This same issue has bitten me as well, I now do exactly as Chris posted, use trough. Besides, it is easer to close up.
 
iwire said:
110.3(B) .......... the LB is listed and it has a clear label, unless we are told otherwise IMO we are stuck with it.
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Not true, the LB does not say MAX ONLY 3 Conductors. The one in question like many say MAX 3- (size of wire). Does not say just 3 conductors. So if you need to fill LB to capacity with more than 3 conductors under the max. I gues you look at the manufacturers fill tables like the one I posted. That IMHO is code compliant unless you can prove it's not.
 
iwire said:
110.3(B) .......... the LB is listed and it has a clear label, unless we are told otherwise IMO we are stuck with it.
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I agree, the LB is already smaller than required by the 6X rule. The number and conductor size listed on the LB gives you more leniency due to it being tested and listed by the manufacturer for those specific conductors.
 
I have had some inspectors turn down LB's even though they had exactly the wire sizes and quantity marked on it, they were ignoring the exception in the code and going with the 6X. I hate LB's for big wire anyway, like Chris and IWire said, it's much easier using the wireway, less chance of skinning a wire. I had a project manager send out LB's on one generator job instead of the usual pull box, the wires were already pulled and terminated in the T'switch, ready to terminate afterhours when the store closed. Since I arrive the day of the changeover, I double check my guys installation, before I give the green light for the shutdown. Sure enough, "C" phase had a short to ground, with 6 sets of paralell 650 kcmil's had to bust apart all "C" phases find which one was shorted, pull it back through the LB, and have it ready again before the scheduled shut down time. Loads of fun.
 
chris kennedy said:
Price the LB, price a 6?6?36 wireway and my time to make two KO's. Now price your time dealing with the inspector. I have the same problem here and until we can all get on the same page, the Kennedy method for 4 wire installs.
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What do you do when it's outdoors and you need to mount one vertically? To get the height you need also makes for a much wider box. His 3" pipe would probably take a 24"H x 18"W x 10"D minimum. I think an LB would look much cleaner.

http://www.b-line.com/product/PDFLibrary/electricalenclosures/index.htm
 
chevyx92 said:
I don't know the article the inspector quoted yet. But just got word he failed me for having a 3" PVC LB with (4) 250 MCM AL and (1) #4 AL in the LB. From what I heard he's saying you can't have more than 3 wires in an LB!! Max fill on this 3" LB says this: MAX 3-350MCM , 178 CU IN. How am I over this? And how can he say you can only ever have 3 wires in an LB? :confused: This is starting to become a HUGE issue in a nearby city we work in. I am trying to figure out this madness because the way they are inspecting LB's and failing because of them, you might as well never use one ever again! Bottom line is if you have more then 3 wires then you are wrong according to this city, which I want to fight because then every LB existing in this world is wrong then. Need some insight please.
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And your under 3 -350 tell him back off or go after him. He wont like it but push it down his throut. Your not in violation as stamped. Go after him .
 
Maybe im reading it wrong but wouldn't 314.28(C) allow the use of smaller LB's that have combinations of conductors.

(3) Smaller Dimensions.

Boxes or conduit bodies of dimensions less than those required in 314.28(A)(1) and (A)(2) (6 times or 8 times) 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,)53,31,40% ........ provided the box or conduit body has been listed for, and is permanently marked with, the maximum number and maximum size of conductors permitted.


Meaning that the 3" lb that is smaller that the 6 X rule can be used, and shall be permitted for installations of combinations of conductors can be used??:?
 
RUWired said:
Maybe im reading it wrong but wouldn't 314.28(C) allow the use of smaller LB's that have combinations of conductors.

(3) Smaller Dimensions.

Boxes or conduit bodies of dimensions less than those required in 314.28(A)(1) and (A)(2) (6 times or 8 times) 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,)53,31,40% ........ provided the box or conduit body has been listed for, and is permanently marked with, the maximum number and maximum size of conductors permitted.


Meaning that the 3" lb that is smaller that the 6 X rule can be used, and shall be permitted for installations of combinations of conductors can be used??:?
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Exactly. .
 
chris kennedy said:
Price the LB, price a 6?6?36 wireway and my time to make two KO's. Now price your time dealing with the inspector. I have the same problem here and until we can all get on the same page, the Kennedy method for 4 wire installs.

DSCN0516.jpg
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what a cheap looking LB... it's made of....... bent tin?:smile:

most people i've run into around here go on the premise that if you are using
a 3/4" conduit, and use a 3/4" LB, then anything that is legal to put in a
3/4" conduit is legal to go thru the LB.

hm. that has too much logic to be applicable under the nec. strike that.
 
Per section 314.28 (A) that is for conductors of 4 AWG or larger. How many #4's can you get in a piece of 3/4" ?
 
I have found that the Carlon conduit bodies have less available room than other brands, such as Cantex, or Kraloy.

Check the brand you are using, it does make a difference. :roll:
 
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