Allowable Ampacities Insulated Conductors (In a Raceway)
Source: Table 310-16 1996 N.E.C.
| TEMP | 60 C | 75 C | 90 C | 60 C | 75 C | 90 C |
| AWG | THW | THW | ||||
| TW | THWN | TW | THWN | |||
| MCM | UF | USE | THHN | UF | USE | THHN |
| COPPER |
ALUMINUM | |||||
| 18 | 14* | |||||
| 16 | 18* | |||||
| 14 | 20* | 20* | 25* | |||
| 12 | 25* | 25* | 30* | 20* | 20* | 25* |
| 10 | 30* | 35* | 40* | 25* | 30* | 35* |
| 8 | 40 | 50 | 55 | 30 | 40 | 45 |
| 6 | 55 | 65 | 75 | 40 | 50 | 60 |
| 4 | 70 | 85 | 95 | 55 | 65 | 75 |
| 3 | 85 | 100 | 110 | 65 | 75 | 85 |
| 2 | 95 | 115 | 130 | 75 | 90 | 100 |
| 1 | 110 | 130 | 150 | 85 | 100 | 115 |
| 1/0 | 125 | 150 | 170 | 100 | 120 | 135 |
| 2/0 | 145 | 175 | 195 | 115 | 135 | 150 |
| 3/0 | 165 | 200 | 225 | 130 | 155 | 175 |
| 4/0 | 195 | 230 | 260 | 150 | 180 | 205 |
| 250 | 215 | 255 | 290 | 170 | 205 | 230 |
| 300 | 240 | 285 | 320 | 190 | 230 | 255 |
| 350 | 260 | 310 | 350 | 210 | 250 | 280 |
| 400 | 280 | 335 | 380 | 225 | 270 | 305 |
| 500 | 320 | 380 | 430 | 260 | 310 | 350 |
| 600 | 355 | 420 | 475 | 285 | 340 | 385 |
| 700 | 385 | 460 | 520 | 310 | 375 | 420 |
| 750 | 400 | 475 | 535 | 320 | 385 | 435 |
Unless otherwise specifically permitted elsewhere in the National Electrical
Code Book, the overcurrent protection for conductor types marked with an asterisk
shall not exceed 15 amperes for No. 14, 20 amperes for No. 12 & 30 amperes
for No. 10 copper; or 15 amperes for No. 12 & 25 amperes for No. 10
aluminum & copper-clad aluminum after any correction factors for ambient
temperature & number of conductors has been applied.