| Size, mm² |
Conductor diameter, mm |
Copper | Aluminium | ||||
|---|---|---|---|---|---|---|---|
| Current, A | Power, kW | Current, A | Power, kW | ||||
| 220 V | 380 V | 220 V | 380 V | ||||
| 0.5 | 0.80 | 6 | 1.30 | 2.30 | — | — | — |
| 0.75 | 0.98 | 10 | 2.20 | 3.80 | — | — | — |
| 1.0 | 1.13 | 14 | 3.10 | 5.30 | — | — | — |
| 1.5 | 1.38 | 15 | 3.30 | 5.70 | 10* | 2.20 | 3.80 |
| 2.0 | 1.60 | 19 | 4.20 | 7.20 | 14* | 3.10 | 5.30 |
| 2.5 | 1.78 | 21 | 4.60 | 8.00 | 16 | 3.50 | 6.10 |
| 4.0 | 2.26 | 27 | 5.90 | 10.30 | 21 | 4.60 | 8.00 |
| 6.0 | 2.76 | 34 | 7.50 | 12.90 | 26 | 5.70 | 9.90 |
| 10 | 3.57 | 50 | 11.00 | 19.00 | 38 | 8.40 | 14.40 |
| 16 | 4.51 | 80 | 17.60 | 30.40 | 55 | 12.10 | 20.90 |
| 25 | 5.64 | 100 | 22.00 | 38.00 | 65 | 14.30 | 24.70 |
| 35 | 6.68 | 135 | 29.70 | 51.30 | 75 | 16.50 | 28.50 |
| 50 | 7.98 | 175 | 38.50 | 66.50 | 105 | 23.10 | 39.90 |
| 70 | 9.44 | 215 | 47.30 | 81.70 | 135 | 29.70 | 51.30 |
| 95 | 11.00 | 260 | 57.20 | 98.80 | 200 | 44.00 | 76.00 |
| 120 | 12.36 | 300 | 66.00 | 114.00 | 230 | 50.60 | 87.40 |
| 150 | 13.82 | 330 | 72.60 | 125.40 | 255 | 56.10 | 96.90 |
How to use
Work out the load current or power and the conductor material (copper or aluminium), then go up the column to a value not less than yours - the row on the left gives the minimum required cross-section. Copper carries more current at the same size, so a copper wire can be thinner than an aluminium one for the same load.
About aluminium
* For fixed wiring, aluminium is used starting from 2.5 mm² - thinner sizes are not sold at retail and are too brittle for terminals. The 1.5 and 2.0 mm² values are given for thermal reference only. In addition, indoor wiring of residential and public buildings is required to be copper, and aluminium is mostly allowed from 16 mm² upwards (service entrances, risers, feeders).
About power
The power values are the product of voltage and
current (P = U · I) at a power factor of 1, rounded to the nearest 0.01 kW.
The "220 V" column is for a single-phase supply, "380 V" - for a load on 380 V line voltage.
The conductor diameter is for a solid conductor and relates to the cross-section
as d = 2·√(S/π); a stranded conductor of the same size has a slightly
larger bundle diameter.
Important
The table sizes the conductor for heating by the load current. A long run must additionally be checked for voltage drop and matched to the circuit breaker rating (maximum cable length table). The values are for reference and depend on installation method and temperature; the actual design should be done by a qualified electrician.