Final derated ampacity
30 A
30 A × 1 ambient × 1 CCC.
NEC 310.15(B)(1) · 310.15(C)(1)
Calculator 13 / NEC 310.15
Ampacity derating
Apply ambient-temperature and current-carrying-conductor adjustments to the NEC Table 310.16 base ampacity.
Conductor and installation inputs
Ambient factors use Table 310.15(B)(1) rows; CCC adjustment uses Table 310.15(C)(1). Terminal ratings under 110.14(C) can govern the usable base column.
Loading saved calculations…
Saved on this device · no cloud sync
VoltForgeAmpacity Derating Report
Project / job name: —
Date: —
Site: voltforgelab.com
Inputs
| Conductor | copper 12 AWG, 90°C; 30°C ambient; 3 CCC |
Results
Load verdict
—
Optional load current not entered.
NEC 110.14(C) · Table 310.16
Engineering disclaimer: This design aid is not a substitute for engineering judgment. Confirm final design with a licensed professional engineer and the authority having jurisdiction.
Base ampacity
30 A
Base value at 30°C ambient and up to three CCC.
NEC Table 310.16 · 90°C copper
Correction factors
1 × 1
Ambient 30°C factor 1; 3 CCC factor 1.
NEC 310.15(B)(1) · 310.15(C)(1)
How this was calculated
- Look up 12 AWG copper in the 90°C Table 310.16 column: 30 A.
- Apply Table 310.15(B)(1) ambient factor 1 and Table 310.15(C)(1) CCC factor 1.
- 30 × 1 × 1 = 30 A.
Engineering disclaimer: Verify terminal temperature limitations under NEC 110.14(C), conductor insulation listing, raceway conditions, and AHJ requirements.