Table 310.85 Ampacities of Three Triplexed Single Insulated Copper Conductors Directly Buried in Earth Based on Ambient Earth Temperature of 20°C (68°F), Arrangement per Figure 310.60, 100 Percent Load Factor, Thermal Resistance (RHO) of 90, Conductor Temperatures 90°C (194°F) and 105°C (221°F)
| Conductor Size (AWG or kcmil) | Temperature Rating of Conductor | |||
| 2001 - 5000 Volts Ampacity | 5001 - 35,000 Volts Ampacity | |||
| 90°C (194°F) Type MV-90 | 105°C (221°F) Type MV-105 | 90°C (194°F) Type MV-90 | 105°C (221°F) Type MV-105 | |
| One Circuit, Three Conductors (See Figure 310.60, Detail 7.) | ||||
| 8 | 90 | 95 | – | – |
| 6 | 120 | 130 | 115 | 120 |
| 4 | 150 | 165 | 150 | 160 |
| 2 | 195 | 205 | 190 | 205 |
| 1 | 225 | 240 | 215 | 230 |
| 1/0 | 255 | 270 | 245 | 260 |
| 2/0 | 290 | 310 | 275 | 295 |
| 3/0 | 330 | 360 | 315 | 340 |
| 4/0 | 375 | 405 | 360 | 385 |
| 250 | 410 | 445 | 390 | 410 |
| 350 | 490 | 580 | 470 | 505 |
| 500 | 590 | 635 | 565 | 605 |
| 750 | 725 | 780 | 685 | 740 |
| 1000 | 825 | 885 | 770 | 830 |
| Two Circuits, Six Conductors (See Figure 310.60, Detail 8.) | ||||
| 8 | 85 | 90 | – | – |
| 6 | 110 | 115 | 105 | 115 |
| 4 | 140 | 150 | 140 | 150 |
| 2 | 180 | 195 | 175 | 190 |
| 1 | 205 | 220 | 200 | 215 |
| 1/0 | 235 | 250 | 225 | 240 |
| 2/0 | 265 | 285 | 255 | 275 |
| 3/0 | 300 | 320 | 290 | 315 |
| 4/0 | 340 | 365 | 325 | 350 |
| 250 | 370 | 395 | 355 | 380 |
| 350 | 445 | 480 | 425 | 455 |
| 500 | 535 | 575 | 510 | 545 |
| 750 | 650 | 700 | 615 | 660 |
| 1000 | 740 | 795 | 690 | 745 |