Lapp Online Catalog: National Electrical Code Allowable Conductor Ampacity

National Electrical Code
Allowable Conductor Ampacity
Table 310-16

Allowable Ampacities of Insulated Conductors Rated 0-2000 Volts, 60° to 90°C (140° to 194°F) NOT MORE THAN THREE CONDUCTORS in Raceway or Cable or Earth (Directly Buried), Based on Ambient Temperature of 30°C (86°F)
Size	Temperature Rating of Conductor
AWG (kcmil)	60°C (140°F)	75°C (167°F)	90°C (194°F)
	TYPES	TYPES	TYPES
	TW†, UF†	FEPW†, RH†, RHW†, THHW†, THW†, THWN†, XHHW†, USE†, ZW†	TA, TBS, SA, SIS, FEP†, FEPB†, MI, RHH†, RHW-2, THHN†, THHW†, THW-2, THWN-2, USE-2, XHH, XHHW†, XHHW-2, ZW-2
	COPPER
18	....	....	14
16	....	....	18
14	20 †	20 †	25 †
12	25 †	25 †	30 †
10	30	35 †	40 †
8	40	50	55
6	55	65	75
4	70	85	95
3	85	100	110
2	95	115	130
1	110	130	150
1/0	125	150	170
2/0	145	175	195
3/0	165	200	225
4/0	195	230	260
250	215	255	290
300	240	285	320
350	260	310	350
400	280	335	380
500	320	380	430
600	355	420	475
700	385	460	520
750	400	475	535
800	410	490	555
900	435	520	585
1000	455	545	615
1250	495	590	665
1500	520	625	705
1750	545	650	735
2000	560	665	750
† Unless otherwise specifically permitted in this Code, the overcurrent protection for conductor types marked with an ebelisk (†) shall not exceed 15 amperes for No.14, 20 amperes for No.12, and 30 amperes for No.10 copper, after any correction factors for ambient temperature and number of conductors have been applied.

Allowable Ampacities of Single Insulated Conductors
Rated 0 through 2000 Volts, in Free Air
Based on Ambient Air Temperature of 30ºC (86ºF)

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