feeder grounded conductor

[simonmidvt]

I have a 277/480V 100A feeder to a solar sub-panel run in rigid conduit. It is fed off of a 100A breaker from the main 800A panel. It runs out of the mechanical room to the roof to a junction box where i ran a 2" rigid to a solar system disconnect at ground level. In that conduit i ran 6 hot conductors (3 down 3 back) and a ground. From the junction box i then ran to the solar sub panel and inverters etc. The neutral goes straight from the breaker to the solar sub panel not to the disconnect. Is this legal? or does my neutral need to go to the disconnect even though it does nothing!!!

Please help

 

[Dennis Alwon]

How would you get around art. 300.3(B). I am not familiar with solar installs-- perhaps there is something there.

300.3(B) Conductors of the Same Circuit. All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord, unless otherwise permitted in accordance with 300.3(B)(1) through (B)(4).

 

[simonmidvt]

I didn't see anything in 590. I saw 300.3 B and saw the "where used" and first interpretation thought that that conductor isn't used. I thought that the intent was that you couldn't run a separate pipe for each conductor or mix of conductors.

 

[curt swartz]

From your description it sounds like the installation is fine. If you had run the line an loads in separate raceways the neutral wound need to installed in each raceway but since all of you line and load conductors are together the neutral is not needed. Think of it as a normal switch loop.

 

[Dennis Alwon]

From your description it sounds like the installation is fine. If you had run the line an loads in separate raceways the neutral wound need to installed in each raceway but since all of you line and load conductors are together the neutral is not needed. Think of it as a normal switch loop.

I agree with Curt, if that is what you have there. I guess I didn't read it that way thus I was asking about 300.3.

 

[iwire]

It sounds fine to me as well, it is just a large switch leg.

However the derating will likely be an issue.

 

[simonmidvt]

That is what i thought do you have any where in the code to back it up. I cant find anything either way.

 

[RUWired]

That is what i thought do you have any where in the code to back it up. I cant find anything either way.

Dennis quoted you the article. There are two words in the article that allow the switch leg. (where used). In the switch leg application your not using the grounded conductor.

Rick