THHN dimensions
Nominal calculation, not one manufacturer's datasheet. The conductor is NEC Chapter 9 Table 8; the insulation and nylon walls are the nominal values the makers catalogue, because UL 83, UL 44 and UL 854 were not read. A wire of the same name can differ slightly: check its datasheet before you specify or order.
Each row is one THHN size in copper at 600 V: the conductor from NEC Table 8, the walls as the makers catalogue them. Open a row for every layer and its source. What THHN means, letter by letter.
North American building wire, 600 V (AWG / kcmil) · 24 sizes
| Size | Rating | Insulation mm | Overall diameter mm | Weight (approximate) kg/km |
|---|---|---|---|---|
| 14 AWG | 600 V | 0.38 | 2.8 | 20 |
| 12 AWG | 600 V | 0.38 | 3.2 | 40 |
| 10 AWG | 600 V | 0.51 | 4.1 | 60 |
| 8 AWG | 600 V | 0.76 | 5.4 | 90 |
| 6 AWG | 600 V | 0.76 | 6.3 | 140 |
| 4 AWG | 600 V | 1.02 | 8.1 | 230 |
| 3 AWG | 600 V | 1.02 | 8.7 | 280 |
| 2 AWG | 600 V | 1.02 | 9.5 | 350 |
| 1 AWG | 600 V | 1.27 | 11.1 | 450 |
| 1/0 AWG | 600 V | 1.27 | 12.1 | 550 |
| 2/0 AWG | 600 V | 1.27 | 13.2 | 690 |
| 3/0 AWG | 600 V | 1.27 | 14.5 | 850 |
| 4/0 AWG | 600 V | 1.27 | 15.9 | 1,060 |
| 250 kcmil | 600 V | 1.52 | 17.6 | 1,270 |
| 300 kcmil | 600 V | 1.52 | 19.0 | 1,510 |
| 350 kcmil | 600 V | 1.52 | 20.2 | 1,750 |
| 400 kcmil | 600 V | 1.52 | 21.4 | 1,990 |
| 500 kcmil | 600 V | 1.52 | 23.5 | 2,460 |
| 600 kcmil | 600 V | 1.78 | 26.0 | 2,970 |
| 700 kcmil | 600 V | 1.78 | 27.8 | 3,450 |
| 750 kcmil | 600 V | 1.78 | 28.6 | 3,680 |
| 800 kcmil | 600 V | 1.78 | 29.4 | 3,920 |
| 900 kcmil | 600 V | 1.78 | 31.0 | 4,390 |
| 1000 kcmil | 600 V | 1.78 | 32.4 | 4,870 |