220.61(B)(2) Derating Neutral

[dhsvcs]

According to 220.61(B)(2), This should work. When can this NOT be used if I have a 4 wire 120/240 Delta Feed High Leg and have a Delta, NOT wye system. I have a 408 A neutral load with 500 MCM thwn-2 cu wire. At 80% of the 90C rating, I should be good to go.

 

[dhsvcs]

see attached...

 

[infinity]

Looks good to me, why the 6 CCC's are there two sets in one raceway?

 

[dhsvcs]

yes..2 sets of 600 mcm for A and C ( or B after the disconnect )..

 

[LarryFine]

The 120/240v 1ph section of a high-leg 3ph delta is identical to that of a 120/240v 1ph.