310.15(B)(1): Temp. Correction Factors

Ambient Temperature Correction Factors Based on 30°C (86°F).

Source: NEC 2020

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Ambient Temp (°C)	Ambient Temp (°F)	60°C	75°C	90°C
10 or less	50 or less	1.29	1.20	1.15
11 - 15	51 - 59	1.22	1.15	1.12
16 - 20	60 - 68	1.15	1.11	1.08
21 - 25	69 - 77	1.08	1.05	1.04
26 - 30	78 - 86	1.00	1.00	1.00
31 - 35	87 - 95	0.91	0.94	0.96
36 - 40	96 - 104	0.82	0.88	0.91
41 - 45	105 - 113	0.71	0.82	0.87
46 - 50	114 - 122	0.58	0.75	0.82
51 - 55	123 - 131	0.41	0.67	0.76

Related NEC Tables

Table 310.16: Allowable Ampacity Table 310.15(C)(1): Adjustment Factors

Professional Usage

This data is provided for informational purposes only. Always verify with the latest edition of the National Electrical Code (NFPA 70) and consult with a licensed electrical professional or AHJ (Authority Having Jurisdiction) before performing any electrical work.

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