ECN Forum Forums Code Related Discussion NEC & other Code issues Grounded cond. ?

Someone posed this ? to me.

Can someone land branch circuit neutrals onto a terminal in a separate enclosure and then continue the run back to the panel with a larger wire.

Assume the hots are run thru the same conduit.

I know its a weird question, but it was posed to me and I would like to make sure I quote the proper code that would not allow this.

You can if it is a "column" panel. See 300.3(B)(3). 225.7 and 215.4 would also permit a common neutral. What is the application involved in your question?
Don

I don't have time to look it up, but I seem to recall reading something to the effect
that the grounded conductors must return
to the panel of the un-grounded conductor
origin.

I guess in theory that method would be returning to the panel of origin.

With so many possibilities and code exceptions, as resqcapt says
What is the application specifically?

Maybe 99NEC300-3. (b) Conductors of the Same Circuit—and—300-20. Induced Currents in Metal Enclosures or Metal Raceways.

I have seen a "neutral block" installed in a 10x10 troff (wireway), the #12 & #10 neutrals terminated on the "block" and a #1 neutral from the "block" to the neutral bus in the panel.

I have also seen the same arrangement with grounds terminated at the troff, and a larger ground terminated at the panel.

The above jobs were inspected and approved
John

This I believe was a typical residential service where the new panel was going to be in a new location. The contractor wanted to know if could use the existing neutral terminal and run one larger conductor from the old panel (which is now going to be gutted and used as a j-box) to the new panel, while carrying the hots for each of the existing circuits back to the new panel using separate conductors.

FYI-conduit is required in our municipality so separate cable runs are not a concern.

Steve T

When will Chicago and some of the bedroom communities begin to allow other wiring methods such as "Romex or BX?"

What is the problem there?

Is it related to a concern over some older rules and political influence by the electrical inspectors?

Joe,

I think you changed the topic, but just in case there is a correlation I missed...

Chicago is a strong union, steel manufacturing city. Fire statistics are supposedly low from electrical installations. (Not that I trust anyone's stats.) To answer your question, I doubt you'll see it unless a horribly corrupt union starts turning out unqualified electricians and problems start occuring.

I personally like the requirement because emt is a higher standard of installation than any type of cable. Additional circuit can be readily added or repaired or replaced with much less cost in the future.

EMT as an equipment grounding conductor is much more reliable than a wire over the long term life of an electrical system. Even BX that was allowed to be installed in Oak Park in the past is in many cases discovered with loose or disconnected connections. I see it every day. I constantly have to tell the electricians to tighten and secure BX connections that were "existing", when the back of bathroom, kitchen etc. walls get opened for a remodel.

I see much less old black pipe with loose connections. Also the walls did not have to get ripped open to replace the old cloth wiring.

If Romex was allowed, in my opinion, the number of non-code compliant, and severly dangerous installations would increase drastically in a period of 5 to 10 years.

I have worked in FL for a period of four years. The problems with electrical installations I saw in FL were more dangerous and much more costly to repair.

Of course, I grew up in Chicago and may have a biased opinion. Then again I may be completely objective.

Problem? Higher standards than the NEC is not a problem.

Oh by the way,

To date there have been almost 1200 electrical permits pulled this year alone in Oak Park. Oak Park has a population of about 60,000 and about 14,000 addresses. Having to run emt has not caused any type of slow down in construction.

Here! Here! I couldn't agree with Steve more.