Table • Current Carrying Capacity • Cross-Section
A guideline overview of the current carrying capacity of cables and wires. The actual capacity depends on installation method, temperature, grouping and applicable standards.
| Cross-Section | Typical Guideline | Note |
|---|---|---|
| 1.5 mm² | commonly up to approx. 16 A | depends on installation method |
| 2.5 mm² | commonly up to approx. 20–25 A | check protective devices |
| 4 mm² | commonly up to approx. 25–32 A | check standard values |
| 6 mm² | commonly up to approx. 32–40 A | temperature-dependent |
| 10 mm² | commonly up to approx. 50–63 A | installation method is decisive |
Current carrying capacity does not depend on cross-section alone, but also on installation method, ambient temperature, grouping, insulation material, number of loaded conductors and protective devices.
FAQ
Briefly explained: formula, use case and key limits of the calculation.
It serves as a guideline for the currents cables can carry depending on cross-section and the given conditions.
Heat dissipation varies with the installation method. This changes the permissible current carrying capacity.
No. Cross-section alone is not enough. Protective devices, installation method, cable type, ambient temperature and grouping must also be considered.
No. The table is a guideline and does not replace standards-compliant planning or inspection by a qualified electrician.
Practical guidance
A conductor size has no single universal current rating. Installation method, insulation, ambient temperature, grouping and loaded conductors all matter.
Thermal insulation, grouped circuits or high ambient temperature can reduce the allowable current shown by a reference condition.
Tabulated value × temperature factor × grouping factor = design value
Do not derive a fuse rating from conductor size alone. This table is an overview, not an installation certificate.
A defensible result needs cable type, reference method, temperature, loaded-core count and correction factors, followed by voltage-drop and fault checks.
