AWG ampacity at 60, 75 and 90 °C, and the copper size for any load and run length with voltage drop taken into account. One sheet, fits A4 and US Letter.
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Copper wire size
AWG ampacity · size by load and distance · voltage drop included
tililt.com
Copper ampacity (NEC 310.16)
AWG
mm²
60 °C
75 °C
90 °C
OCPD max
Ω / 1000 ft
14
2.1
15
20
25
15*
3.14
12
3.3
20
25
30
20*
1.98
10
5.3
30
35
40
30*
1.24
8
8.4
40
50
55
0.778
6
13.3
55
65
75
0.491
4
21.2
70
85
95
0.308
3
26.7
85
100
115
0.245
2
33.6
95
115
130
0.194
1
42.4
110
130
145
0.154
1/0
53.5
125
150
170
0.122
2/0
67.4
145
175
195
0.0967
3/0
85.0
165
200
225
0.0766
4/0
107
195
230
260
0.0608
250 kcmil
127
215
255
290
0.0515
300 kcmil
152
240
285
320
0.0429
350 kcmil
177
260
310
350
0.0367
400 kcmil
203
280
335
380
0.0321
500 kcmil
253
320
380
430
0.0258
Copper size by load and one-way distance — 240 V, 1-phase, 3% drop
Load
25 ft
50 ft
75 ft
100 ft
125 ft
150 ft
200 ft
250 ft
300 ft
15 A
14
14
14
12
10
10
8
8
8
20 A
12
12
12
10
10
8
8
6
6
30 A
10
10
10
8
8
8
6
4
4
40 A
8
8
8
8
6
6
4
4
3
50 A
8
8
8
6
6
4
4
3
2
60 A
6
6
6
6
4
4
3
2
2
70 A
4
4
4
4
4
4
3
2
1
80 A
4
4
4
4
4
3
2
1
1/0
100 A
3
3
3
3
3
2
1
1/0
2/0
125 A
1
1
1
1
1
1
1/0
2/0
3/0
150 A
1/0
1/0
1/0
1/0
1/0
1/0
2/0
3/0
3/0
175 A
2/0
2/0
2/0
2/0
2/0
2/0
2/0
3/0
4/0
200 A
3/0
3/0
3/0
3/0
3/0
3/0
3/0
4/0
250k
Shaded = voltage drop, not current,
sets the size. 250k = 250 kcmil. At 120 V read the column for double the
distance.
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