1/0 AWG (American Wire Gauge) wire specifications: 8.2515 mm diameter, 53.4751 mm² area, 150A ampacity (copper, 75°C). Resistance, weight, and common uses.
| Diameter | 8.2515 mm · 0.324861" · 324.86 mils |
| Cross-sectional area | 53.4751 mm² · 105,534 circular mils |
| Resistance (copper, 20°C) | 0.3224 Ω/km · 0.0983 Ω/1000ft |
| Resistance (aluminum, 20°C) | 0.5285 Ω/km · 0.1611 Ω/1000ft |
| Ampacity — copper 60°C | 125 A |
| Ampacity — copper 75°C | 150 A |
| Ampacity — copper 90°C | 170 A |
| Ampacity — aluminum 75°C | 120 A |
| Weight (copper) | 479.137 kg/km · 321.965 lbs/1000ft |
| Weight (aluminum) | 144.383 kg/km · 97.021 lbs/1000ft |
| Closest IEC 60228 size | 50 mm² |
| Skin depth at 60 Hz | 8.531 mm |
| Type | Temperature | Description |
|---|---|---|
| THHN/THWN-2 | 90°C dry / 75°C wet | Most common for building wire |
| XHHW-2 | 90°C dry and wet | Cross-linked polyethylene, moisture resistant |
| USE-2 | 90°C | Underground service entrance |
| NM-B (Romex) | 90°C | Non-metallic sheathed cable for residential |
| UF-B | 60°C | Underground feeder, direct burial |
1/0 AWG copper is commonly used for 100–125A feeders and service-entrance conductors. NEC Table 310.16 rates it 150A at 75°C. It measures 8.252 mm in diameter with a 53.5 mm² cross-section.
Per NEC Table 310.16 (30°C ambient, no more than three current-carrying conductors), 1/0 AWG copper is rated 125A at 60°C, 150A at 75°C and 170A at 90°C. 1/0 AWG aluminum is rated 100A, 120A and 135A in the same columns. Above 100A, NEC 110.14(C) allows the 75°C column when terminations are rated 75°C.
Yes. 1/0 AWG aluminum is rated 120A at 75°C versus 150A for copper, so matching the copper rating takes 3/0 AWG aluminum. Aluminum at this size is common for feeders, subpanels and service conductors (SER, USE-2, XHHW-2). Use AL-rated lugs, torque to the manufacturer’s spec and apply antioxidant compound where required.