): The final rated current is found by multiplying the adiabatic current by the non-adiabatic factor.
IEC 60949:1988 (including Amendment 1:2008) is the international standard for calculating . Unlike simpler methods that assume no heat escapes the conductor (adiabatic), IEC 60949 provides a way to account for non-adiabatic heating effects , where some heat is absorbed by surrounding materials like insulation or sheaths. Key Formulas and Calculation Methods Iec 60949 Pdf Free Download
): This assumes all heat generated by the fault remains within the conductor. ): The final rated current is found by
): A modifying factor is calculated to account for heat dissipation into surrounding layers. Final Permissible Current ( Iec 60949 Pdf Free Download