Mike Dolt Enterprises
Mike Dolt Enterprises
User: Red Wiggler, Location: Tennessee
Asked on: Monday, March 28, 2011 at 3:56 pm EDT
Answered on: Tuesday, May 14, 2024 at 3:23 am EDT
Question: Article 376.22 (A) (B) are references to (A)Cross-Sectional Areas of a Wireway and (B) Adjustment Factors.When discussing the Adjustment Factors this section refers to 310.15(B)(2)(a) when current-carrying conductors exceed 30.Does that mean you begin derating as the table shows 4-6 = 80%? Or does it mean 34-36 = 80% since you have already been given 30 conductors in the raceway that have not been derated?Surely it doesn't mean the first 30 are fully rated and the next 4-6 will be rated at 80%...does it.
The adjustment factors in Article 310.15(B)(2)(a) apply to the total number of current-carrying conductors in the raceway, regardless of whether or not they exceed 30. Therefore, if the raceway contains 34-36 current-carrying conductors, the adjustment factor would be 80%. Flag for review