Conductor Derating

Calculate ampacity derating per NEC 310.15

Derating Results

Minimum Required Ampacity --
Recommended Wire Size --
Load Current --
Continuous Load Factor --
Adjusted Load --
Temperature Correction --
Conduit Fill Factor --
Combined Derating --

Calculation Breakdown

NEC Derating Requirements

Temperature Correction (310.15(B))

When ambient temperature exceeds 30°C (86°F), ampacity must be corrected using Table 310.15(B)(1).

Higher temperature insulation (90°C) has better correction factors.

Conduit Fill (310.15(C))

When more than 3 current-carrying conductors are in a raceway, ampacity must be reduced per Table 310.15(C)(1).

Neutrals carrying unbalanced load count as current-carrying.