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Wire Ampacity Chart
Wire ampacity chart for copper and aluminum conductors from 14 AWG to 600 kcmil at 60 °C, 75 °C and 90 °C, with resistance per 1,000 ft.
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| Size | Cu 60°C | Cu 75°C | Cu 90°C | Al 60°C | Al 75°C | Al 90°C | Ω/1000ft Cu |
|---|---|---|---|---|---|---|---|
| 14 AWG | 15 | 20 | 25 | – | – | – | 3.07 |
| 12 AWG | 20 | 25 | 30 | 15 | 20 | 25 | 1.93 |
| 10 AWG | 30 | 35 | 40 | 25 | 30 | 35 | 1.21 |
| 8 AWG | 40 | 50 | 55 | 35 | 40 | 45 | 0.764 |
| 6 AWG | 55 | 65 | 75 | 40 | 50 | 55 | 0.491 |
| 4 AWG | 70 | 85 | 95 | 55 | 65 | 75 | 0.308 |
| 3 AWG | 85 | 100 | 115 | 65 | 75 | 85 | 0.245 |
| 2 AWG | 95 | 115 | 130 | 75 | 90 | 100 | 0.194 |
| 1 AWG | 110 | 130 | 145 | 85 | 100 | 115 | 0.154 |
| 1/0 AWG | 125 | 150 | 170 | 100 | 120 | 135 | 0.122 |
| 2/0 AWG | 145 | 175 | 195 | 115 | 135 | 150 | 0.0967 |
| 3/0 AWG | 165 | 200 | 225 | 130 | 155 | 175 | 0.0766 |
| 4/0 AWG | 195 | 230 | 260 | 150 | 180 | 205 | 0.0608 |
| 250 kcmil | 215 | 255 | 290 | 170 | 205 | 230 | 0.0515 |
| 300 kcmil | 240 | 285 | 320 | 195 | 230 | 260 | 0.0429 |
| 350 kcmil | 260 | 310 | 350 | 210 | 250 | 280 | 0.0367 |
| 400 kcmil | 280 | 335 | 380 | 225 | 270 | 305 | 0.0321 |
| 500 kcmil | 320 | 380 | 430 | 260 | 310 | 350 | 0.0258 |
| 600 kcmil | 350 | 420 | 475 | 285 | 340 | 385 | 0.0214 |
Not more than 3 current-carrying conductors in a raceway/cable, 30 °C ambient. Overcurrent protection for 14/12/10 AWG copper is limited to 15/20/30 A (NEC 240.4(D)).
How to use it
- Find your conductor size in the first column.
- Use the column matching the lowest temperature rating of the wire, terminals and equipment (usually 60 °C for ≤100 A / 14-1 AWG unless marked otherwise, 75 °C above).
- Apply derating for more conductors or hotter ambient.
How it works
Ampacity is the current a conductor can carry continuously without exceeding its insulation temperature rating. The 90 °C column is mainly used as the starting point for derating.
FAQ
How many amps can 12 gauge wire handle?
12 AWG copper is rated 20 A at 60 °C and 25 A at 75 °C, but the breaker is limited to 20 A.
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