Grounded (neutral) conductors - InspectionNews

George Hodge · #1 (**permalink**) 04-10-2007, 12:13 PM

Are the grounded (neutral) conductors in a panel enclosure parallel? And if so, then as I understand the exception to Article 408.21 of the 2002 NEC the grounded (Neutral) conductors in a Cutler Hammer panel can have more than one conductor in a terminal (lug). Is this correct since Cutler Hammer panels state that their terminals can accept more than one conductor? I have been calling out these panels since the Article 408.21 states "Each grounded conductor shall terminate within the panelboard in an individual terminal that is not also used for another conductor". Have I been in error?

Tim Moreira · #2 (**permalink**) 04-10-2007, 01:34 PM

I would allow it as long as the panel is listed for it.

IMHO

Jerry Peck · #3 (**permalink**) 04-10-2007, 02:12 PM

First, no, then, yes.

But, first, to make sense of your questions.

1) Are the neutral conductors in parallel? No.

2) Have you been in error? Yes.

What the parallel part is referring to are paralleled conductors. Let's say you want to run a 400 amp service. That would require a conductor size of 600 kcmil, which is one big honken size conductor. You could run parallel conductor, so you choose to run 2-3/0 conductors in parallel, which gives you 400 amp.

Those conductors will EACH go into THEIR OWN terminal. However, *IF* the terminal (they are large terminals) is rated for two conductors, than you could put both neutral conductors into the one terminal - which is rated for two conductors. You would do the same thing for the hot conductors too.

However, rather than try to cram the 2-3/0 into that one terminal, you would use a double terminal adapter, installing each 3/0 into its own terminal.

DOES NOT apply to the smaller neutral terminal you are referring to.

Parallel conductors must be 1/0 or larger in size.

George Hodge · #4 (**permalink**) 04-10-2007, 03:28 PM

Jerry, I have read with interest and appreciation your posts on this board and respect you opinion and view. The grounded conductors that I have been calling out are the 110v. circuit neutrals terminated on the bus bars. I took article 408.21 to mean that even if the bus bar could accept more than one neutral conductor it still was contrary to the article. Is this wrong?

Jerry Peck · #5 (**permalink**) 04-10-2007, 06:20 PM

I thought you were saying that you had been saying (are you as confused as I was?

) they were "OK."

Now, though, I read it as you saying you have been saying "Not OK."

You would be correct if you have been saying "Not OK."

I think I am/was/are confused about what you said.

What's the PC way to state that ... I misread what you wrote?

Tim Moreira · #6 (**permalink**) 04-10-2007, 07:15 PM

Quote:

conductor size of 600 kcmil, which is one big honken size conductor

Jerry,

I could not find that term in the NEC definitions? Is that a technical term?

Jerry Peck · #7 (**permalink**) 04-11-2007, 09:15 AM

Tim,

Yes. Technical term.

It's just up the list, alphabetically, from "Thingy".