Ampacity Chart
TABLE B-310-1
AMPACITIES OF TWO OR THREE INSULATED CONDUCTORS
Rated 0 through 2000 volts, with an overall covering (Multiconductor), on
Raceway in Free Air Based on Ambient Air Temperature of 30°C (86°F)
SIZE |
TEMPERATURE RATING OF CONDUCTOR, SEE TABLE
310-13 |
SIZE |
AWG
kcmil |
60°C
(140°F) |
75°C
(167°F) |
90°C
(194°F) |
60°C
(140°F) |
75°C
(167°F) |
90°C
(194°F) |
AWG
kcmil |
TYPES
TW, UF |
TYPES
RH, RHW, THHW
THW, THWN |
TYPES
THHN,
THHW |
TYPES
TW |
TYPES
RH, RHW, THHW
THW, THHW |
TYPES
THHN,
THHW |
COPPER |
ALUMINUM OR COPPER-CLAD ALUMINUM |
8
6
4
3
2
1
1/0
2/0
3/0
4/0
250
300
350
400
500
600
700
750
800
900
1000 |
36
48
66
76
88
102
121
138
158
187
205
234
255
274
315
343
376
387
397
415
448 |
43
58
79
90
105
121
145
166
189
223
245
281
305
328
378
413
452
466
479
500
542 |
48
65
89
102
119
137
163
186
214
253
276
317
345
371
427
468
514
529
543
570
617 |
28
38
51
59
69
80
94
108
124
147
160
185
202
218
254
279
310
321
331
350
382 |
33
45
61
70
83
95
113
129
147
176
192
221
242
261
303
335
371
384
397
421
460 |
37
51
69
79
93
106
127
146
167
197
217
250
273
295
342
378
420
435
450
477
521 |
8
6
4
3
2
1
1/0
2/0
3/0
4/0
250
300
350
400
500
600
700
750
800
900
1000 |
Ambient
Temp °C |
For Ambient temperatures other than 30°C (86°F) multiple
the
ampacities shown above by the appropriate factor shown below |
Ambient
Temp °F |
21-25
26-30
31-35
36-40
41-45
46-50
51-55
56-60
61-70
71-80 |
1.08
1.00
.91
.82
.71
.58
.41
-
-
- |
1.05
1.00
.94
.88
.82
.75
.67
.58
.33
- |
1.04
1.00
.96
.91
.87
.82
.76
.71
.58
.41 |
1.08
1.00
.91
.82
.71
.58
.41
-
-
- |
1.05
1.00
.94
.88
.82
.75
.67
.58
.33
- |
1.04
1.00
.96
.91
.87
.82
.76
.71
.58
.41 |
70-77
79-86
88-95
97-104
106-113
115-122
124-131
133-140
142-158
160-176 |