3 #2 Copper AWG and #8 EGC

[DanGarzLU60]

I have been scratching my head regarding this matter. We had a wire pull of (3) #2 copper AWG wires and (1) #8 copper AWG EGC. The run was in 1 1/2” and went through an LB. On the LB it stated “3 #2 AWG MAX”. Brought it to the attention of my foreman and he said if it fits in the conduit then it fits in the LB. We pulled it anyways but I have been trying to solve this since with no luck. Was this legal? Also the LB said 33 cu in.

 

[infinity]

The cubic inches volume is not relevant to your question. Since you have exceeded the three conductors stamped on the conduit body it's a technical violation due to the 6X rule which requires you to follow the information stamped into the conduit body. Anyway I would just leave it since it's done.

Welcome to the Forum.

 

[DanGarzLU60]

What code section are you referring to? I referred my foreman to 110.3(B) regarding the stamp.

 

[infinity]

Take a look at 314.28(A)(3). The LB conduit body needs to meet the 6X rule for angle pulls. If you use the conductor info stamped in the conduit body you can ignore the 6X requirement.

 

[electrofelon]

Brought it to the attention of my foreman and he said if it fits in the conduit then it fits in the LB.

That is incorrect, but very commonly ignored. It is quite annoying and I think a conduit body should be able to take connectors that result in max fill for the raceway.

 

[don_resqcapt19]

That is incorrect, but very commonly ignored. It is quite annoying and I think a conduit body should be able to take connectors that result in max fill for the raceway.

So you want only mogul fittings at 2 to 3 times the cost? The issue is compliance with 314.28.

 

[infinity]

So you want only mogul fittings at 2 to 3 times the cost? The issue is compliance with 314.28.

I certainly don't. When using conduit bodies the installer needs to be aware of the conductor size and quality otherwise another method such as a wireway needs to be used.

 

[electrofelon]

So you want only mogul fittings at 2 to 3 times the cost? The issue is compliance with 314.28.

No. They could still have the smaller dimensions, either just make them a little bigger so they can take the full raceway fill or just allow them to take the full raceway fill as is, everyone does it anyway so what's the problem? How do the manufacturers come up with the max fill for these things anyway?

 

[electrofelon]

UL seems to allow sharp edges on these damn things, which in my mind is a much bigger issue than a little bit more fill, but apparently no one at UL has ever installed anything so there you have it.

 

[dkidd]

Have a look at

https://media.distributordatasolutions.com/ThomasAndBetts/v1/files/File_72203_emAlbumalbumsus_resourceform7835conduitfill_tc1pdfClickHerea.pdf

The fill can be different for different configurations.

 

[don_resqcapt19]

No. They could still have the smaller dimensions, either just make them a little bigger so they can take the full raceway fill or just allow them to take the full raceway fill as is, everyone does it anyway so what's the problem? How do the manufacturers come up with the max fill for these things anyway?

You would never be able to take the full wire fill without making them a lot bigger...a little bigger is not going to do the job.
Not sure everyone uses the full fill...have not seen the large conductors being installed into an LB using a 2x4 and a sledge hammer in a long time

 

[electrofelon]

You would never be able to take the full wire fill without making them a lot bigger...a little bigger is not going to do the job. [/Quote[

Do you know how the marked max sizes are determined?

[Quite[Not sure everyone uses the full fill...have not seen the large conductors being installed into an LB using a 2x4 and a sledge hammer in a long time

I think you are being overly dramatic. I frequently put 250 Pratt urd in a 2" lb, and although that is not Max fill, it's close, and it's really not that hard - except for the silly sharp edges on the LB

 

[CoolWill]

I recently put four 400 kcmil and a ground in an LB marked for three 500s. It was tight but doable.

 

[infinity]

I recently put four 400 kcmil and a ground in an LB marked for three 500s. It was tight but doable.

We've all been there. I once pounded 5-600's into a 4" LB. If you work to mitigate the sharp edges that EF mentioned it can be done without damaging the conductors. We used a combination of cardboard and wire lube. Also helps to feed into the correct side of the conduit body.

 

[LarryFine]

Not sure everyone uses the full fill...have not seen the large conductors being installed into an LB using a 2x4 and a sledge hammer in a long time

Same here; I use a rotary hammer set to hammer mode.

 

[electrofelon]

Alao, if I can keep complaining: the marked sizes don't indicate the insulation type or whether the conductor is compact or not. If I remember correctly, a typical 2-in lb says 3 4/0 Max. Ok, but there is a substantial size difference between 3 4/0 compact XHHW and 3 4/0 non compact USE/RHH.

I checked and Pratt/250 URD is 32% fill in 2" schedule 40. If you were to "convert" that to non compact size, I bet that would be pretty close to the 3-4/0 marked. So you need to increase the size of the lb 25% to reach max raceway fill.

 

[wwhitney]

Alao, if I can keep complaining: the marked sizes don't indicate the insulation type or whether the conductor is compact or not.

The informational note at the end of 314.28(A)(3) says "Unless otherwise specified, the applicable product standards evaluate the fill markings covered here based on conductors with Type XHHW insulation."

Cheers, Wayne

 

[electrofelon]

The informational note at the end of 314.28(A)(3) says "Unless otherwise specified, the applicable product standards evaluate the fill markings covered here based on conductors with Type XHHW insulation."

Cheers, Wayne

Ok good, some clarity. Although still ambiguous regarding compact vs concentric, which is about a one size difference.