300 mm² metric wire specifications (IEC 60228): 19.544 mm diameter, 367A ampacity (copper), closest AWG equivalent is 4/0. Resistance, weight, and common uses.
| Cross-sectional area | 300 mm² |
| Diameter | 19.544 mm |
| Closest AWG equivalent | 4/0 AWG |
| Ampacity (copper) | 367 A |
| Ampacity (aluminum) | 289 A |
| Resistance (copper, 20°C) | 0.0575 Ω/km |
| Resistance (aluminum, 20°C) | 0.0883 Ω/km |
| Weight (copper) | 2688.0 kg/km |
| Weight (aluminum) | 810.0 kg/km |
The IEC 60228 metric system specifies wire by cross-sectional area in mm², while AWG uses a gauge number system. The closest AWG equivalent to 300 mm² is 4/0 AWG, but they are not exactly the same size.
Metric sizes are standard in Europe, Asia, Australia, and most countries outside North America. When replacing or matching wire between systems, always verify the actual cross-sectional area rather than relying on approximate equivalents.