bus bar trough

[hhsting]

I have incoming service with 208/120V three phase 2500A main service breaker which feeds bus bar trough all in one enclosure located outside the building. The bus bar trough I am planning tapping 400A disco 1, 400A disco 2, 4#3/0 to 200A disco 3, 400A disco 4, 400A disco 5 all discos located outside next to the building.


I looked at 240.21(E) for busway tap which points to 368.17 and 368.17(C) exception no.1 again points to 240.21. These are tap conductors from bus bar trough outside the building and was wonder what section of NEC 2014 apply?

 

[infinity]

Is this actually a busway?

 

[hhsting]

Actually I am not sure which NEC article would apply so I just looked in 240.21 and found something related to bus i.e. busway.

To better illustrate attached is a sketch. Its enclosed breaker and bus trough with bus bars Nema 3R enclosure.

 

[Muneepit]

I believe what you have is a bussed gutter, not a busway?

 

[infinity]

I agree not a busway by definition, take a look at Article 366.

366.2 Definitions.
Metallic Auxiliary Gutter. A sheet metal enclosure used to supplement wiring spaces at meter centers, distribution centers, switchgear, switchboards, and similar points of wiring systems. The enclosure has hinged or removable covers for housing and protecting electrical wires, cable, and busbars. The enclosure is designed for conductors to be laid or set in place after the enclosures have been installed as a complete system.

 

[Cow]

I believe what you have is a bussed gutter, not a busway?

I think so.

Is it like this:

https://www.google.com/url?sa=i&rct...aw3DM0WFBo7_Fn8_SCefOCLD&ust=1546886065832317

 

[Muneepit]

Bus bar trough

Bus bar trough

If that is the case, you could tap the gutter and run indefinitely on the exterior to your fussed service disconnects as long as it is on the same building without overcorrect protection.

All agree?

 

[electrofelon]

I am thinking just 240.21(B)(5), the "unlimited tap rule".

 

[electrofelon]

If that is the case, you could tap the gutter and run indefinitely on the exterior to your fussed service disconnects as long as it is on the same building without overcorrect protection.

All agree?

OP has a main service disco, so they would be feeder taps.

 

[Muneepit]

bus bar trough

I agree. I didn't post the code reference with my earlier post.

 

[electrofelon]

If that is the case, you could tap the gutter and run indefinitely on the exterior to your fussed service disconnects as long as it is on the same building without overcorrect protection.

All agree?

I agree. I didn't post the code reference with my earlier post.

But you did say the part in red. They wouldn't be service disconnects. Once could do pretty much the same thing with sets of service entrance conductors, then they would be service disconnects, but they would need to be grouped (usually).