Parallel Neutral Sizing

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I am developing a project that will require 8 parallel sets of 700 kcmil aluminum for a 1000A 480V 3PH-4W circuit. I will utilize a 500 kcmil copper ground for each set.
Per NEC article 215.2(A)(2) I believe I can run a 700 kcmil aluminum in only 1 of the sets as allowed per 250.122(F). Please advise.
 

infinity

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You need the neutral conductor is each raceway. You can reduce its size according to your calculated load all the way down to #1/0 if that works.

(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).
(1) Paralleled Installations. Conductors shall be permitted to
be run in parallel in accordance with the provisions of
310.10(H). The requirement to run all circuit conductors
within the same raceway, auxiliary gutter, cable tray, trench,
cable, or cord shall apply separately to each portion of the
paralleled installation,
and the equipment grounding conduc‐
tors shall comply with the provisions of 250.122. Parallel runs
in cable tray shall comply with the provisions of 392.20(C).
 
You need the neutral conductor is each raceway. You can reduce its size according to your calculated load all the way down to #1/0 if that works.

The calculated circular mils for the neutral is 1200 kcmil aluminum, or 150 kcmil/set which happens to correspond to 3/0. If I understand you correctly, then I could use (8) sets 3x700AL, 3/0AL, 500CU-G. Do you concur?
 
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