Conductor Ambient and Fill Ampacity Adjustment
Adjusted ampacity after the NEC 310.15(B)(1) ambient-temperature and 310.15(C)(1) more-than-three-conductors correction factors.
Formula and source
adjusted_ampacity = base_ampacity * ambient_factor * fill_factor. Ambient factor per 310.15(B)(1) (30 C table basis), fill factor per 310.15(C)(1) (more than three current-carrying conductors).
NEC 2023 (NFPA 70). 310.15(B)(1) (ambient correction) and 310.15(C)(1) (conductor-fill adjustment).
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