Sharing a neutral

[Philip Barr]

If the grounded conductor is sized accordingly you can.

Roger

I'm to tired to fish the book for weather or not there is a specific code that says no, but by this reasoning I'm going to run a #10 neutral for 2 15 amp circuits and an 8 for 20... Good luck terminating your devices.

 

[Mgraw]

Pigtails and wire nuts work OK. I ran 9,000ft of "Super Neutral" with over 400 receptacles. Ungrounded conductors were #12, grounded conductor was a #8.

 

[e57]

Pigtails and wire nuts work OK. I ran 9,000ft of "Super Neutral" with over 400 receptacles. Ungrounded conductors were #12, grounded conductor was a #8.

OK that just sounds bizzare - ONE CIRCUIT 400 Recepts???? Even though I'm sure you mean a MWBC and quite possibley 3 circuits - but i still hope it wasn't 133 each? And I see no need for #8 in proportion to 3-12's... Could you explain the reasoning for that?

 

[Mgraw]

Yes it was multi-circuits and no it wasn't one circuit. The #8 neutral was spec'ed by the EE.

 

[e57]

Yes it was multi-circuits and no it wasn't one circuit. The #8 neutral was spec'ed by the EE.

Well - is that not a contradiction in terms? (And that EE is wacko! )

 

[Mgraw]

I have done alot of work with this EE and he is very good. We had 46 classrooms (2 circuits, 6 receptacles each classroom) 8 computer labs (6 circuits, 18 receptacles each computer lab). He spec'ed super neutral because he was concerned about harmonics.

 

[roger]

I'm to tired to fish the book for weather or not there is a specific code that says no, but by this reasoning I'm going to run a #10 neutral for 2 15 amp circuits and an 8 for 20...

Very good.

Good luck terminating your devices.

I don't think it would be a problem, see McGraws post.
.
Roger

 

[sameguy]

MGraw did you use K rated xformers?

 

[Mgraw]

No. I don't know what transformers were put in. The service to the school was upgraded, new switchgear installed, and 5 new 120/208 panels installed by others. I did not do that part of the job. All my circuits came off the 5 new panels. This job was in three different bids. I did the receptacles and the new fire alarm and intercom system.

 

[James13]

3 hots, 1 neutral from a 3 phase panel is smart