Nec Cable Ampacity: copper
18 AWG to 310.15B17#1/0 AWG
NEC (NFPA 70) cable ampacity ratings — allowable current for copper and aluminum conductors at 60/75/90°C insulation ratings in raceways and free air; high-temperature conductor ampacity at 150/200/250°C; ambient temperature correction factors; conductor fill adjustment factors
| conductor material | conductor size | ampacity 60C (A) | ampacity 75C (A) | ampacity 90C (A) | installation | nec table | standard |
|---|---|---|---|---|---|---|---|
| copper | 18 AWG | — | — | 14 | — | 310.16 | NEC (NFPA 70) 2017 Table 310.15(B)(16) |
| copper | 2 AWG | 95 | 115 | 130 | — | 310.16 | NEC (NFPA 70) Table 310.16 |
| copper | 2/0 AWG | 145 | 175 | 195 | — | 310.16 | NEC (NFPA 70) Table 310.16 |
| copper | 2000 kcmil | 555 | 665 | 750 | — | 310.16 | NEC (NFPA 70) Table 310.16 |
| copper | 250 kcmil | 215 | 255 | 290 | — | 310.16 | NEC (NFPA 70) Table 310.16 |
| copper | 3 AWG | 85 | 100 | 115 | — | 310.16 | NEC (NFPA 70) Table 310.16 |
| copper | 3/0 AWG | 165 | 200 | 225 | — | 310.16 | NEC (NFPA 70) Table 310.16 |
| copper | 300 kcmil | 240 | 285 | 320 | — | 310.16 | NEC (NFPA 70) Table 310.16 |
| copper | 310.15B17#1 AWG | 165 | 195 | 220 | free air | 310.15(B)(17) | NEC (NFPA 70) 2017 Edition Table 310.15(B)(17) |
| copper | 310.15B17#1/0 AWG | 195 | 230 | 260 | free air | 310.15(B)(17) | NEC (NFPA 70) 2017 Edition Table 310.15(B)(17) |
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