120 mm² metric wire specifications (IEC 60228): 12.361 mm diameter, 210A ampacity (copper, IEC 60364-5-52 method A1, PVC, 2 loaded), closest equivalent is 250 kcmil. Resistance, weight, and common uses.
| Cross-sectional area | 120 mm² |
| Diameter (solid equivalent) | 12.361 mm |
| Closest AWG equivalent | 250 kcmil (126.7 mm²); larger than 4/0 AWG |
| Ampacity (copper, IEC 60364-5-52 method A1, PVC, 2 loaded) | 210 A |
| Ampacity (aluminum) | 164 A |
| Max resistance (copper, 20°C, IEC 60228 class 2) | 0.153 Ω/km |
| Max resistance (aluminium, 20°C, IEC 60228) | 0.253 Ω/km |
| Weight (copper) | 1075.2 kg/km |
| Weight (aluminum) | 324.0 kg/km |
The IEC 60228 metric system specifies wire by cross-sectional area in mm², while AWG uses a gauge number system. The closest North American equivalent to 120 mm² is 250 kcmil, 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.
120 mm² metric wire (IEC 60228) is rated 210A (copper, IEC 60364-5-52 method A1, PVC, 2 loaded) and is commonly used for heavy industrial mains, power station distribution, large commercial building supply. Its diameter is 12.36 mm. The closest North American equivalent is 250 kcmil.
120 mm² wire is approximately equivalent to 250 kcmil in the American Wire Gauge system. Note that IEC and AWG sizes do not align exactly — when substituting, choose the AWG size with equal or greater cross-sectional area to ensure adequate ampacity.