100% neutral requirement, is the neutral CCC for conduit fill calculation

[TonyEEINC]

Have a project that requires 100% neutrals, and nothing less than 3/4 emt, this is making the lay out of home run pipes an issue if each neutral is counted for conduit fill.
I understand a balanced load of a full boat, 3 phases, and a neutral, which means the no load on the neutral and not counting it in the pipe fill.
This said the 100% neutral is just three times the conductor area, for the same unbalanced load. So I assume they would not count in the pipe fill.
Still keeping with 9 conductors per pipe!

 

[fmtjfw]

Have a project that requires 100% neutrals, and nothing less than 3/4 emt, this is making the lay out of home run pipes an issue if each neutral is counted for conduit fill.
I understand a balanced load of a full boat, 3 phases, and a neutral, which means the no load on the neutral and not counting it in the pipe fill.
This said the 100% neutral is just three times the conductor area, for the same unbalanced load. So I assume they would not count in the pipe fill.
Still keeping with 9 conductors per pipe!

NO -- a conductor that is in the conduit is counted as part of the fill. Conductors that are not Current Carrying Conductors are not counted for derating purposes.

NOTE -- the neutral and ground wire (green or bare) are counted in conduit fill.

 

[ActionDave]

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Still keeping with 9 conductors per pipe!

Every wire in the pipe counts as pipe fill and in your case the neutrals are counted as CCC. Since you have 3/4 if you want to use 10AWG and 15A breakers you can add one more conductor.

Get used to it. I won't be long before there won't be any MWBC.

 

[Smart $]

Have a project that requires 100% neutrals, and nothing less than 3/4 emt, this is making the lay out of home run pipes an issue if each neutral is counted for conduit fill.
I understand a balanced load of a full boat, 3 phases, and a neutral, which means the no load on the neutral and not counting it in the pipe fill.
This said the 100% neutral is just three times the conductor area, for the same unbalanced load. So I assume they would not count in the pipe fill.
Still keeping with 9 conductors per pipe!

As stated by others, all wires in the conduit count towards fill.

What I'm having a problem with in your description is 100% neutrals vs. dedicated neutrals (Code-AKA Individual Branch Circuits). 100% neutrals IMO means not reduced in size compared to ungrounded conductors. Dedicated neutrals are one neutral for every line-to-neutral load.

 

[infinity]

As stated by others, all wires in the conduit count towards fill.

What I'm having a problem with in your description is 100% neutrals vs. dedicated neutrals (Code-AKA Individual Branch Circuits). 100% neutrals IMO means not reduced in size compared to ungrounded conductors. Dedicated neutrals are one neutral for every line-to-neutral load.

My guess is that the 100% neutral is actually a single dedicated neutral for each phase conductor.

 

[TonyEEINC]

Thanks for making me look at things closer.

Thanks for making me look at things closer.

I have spent some time refreshing myself on the differance of pipe fill, and derating conductors. Should have started there first. Thanks for the comments. The 100% neutral is a fact, when described they expect it to be the same size as the phase conductors, in this case they indicated 100% neutral with 1 per phase, so I could not put 3 smaller neutrals in place.
Then who ever layed out all the circuits has them scattered all over the place, with 3 circuits in each 3/4 emt, a bird cant fly thur the ceiling without hitting a pipe.....
Thanks again.
Sometimes you just need to think a little more, and open the book.
Tony