tukang listrik said:
hello there, i have a problem and need some solutions from all fellows here.
are there any formulas that can show the relationship between the area of cable, its purity of the material, and the current capacity? until now i mostly find just the table of the ampacity, but don't know how to calculate it.
Dear Tukang ;
First, the calculation methode of the nominal current for any cable, accordingly the the section & material, is very complicated, so, it's better to refer not the tables of manufacturers but to the table of ” IEC 60364-5-52 “ where you can find the nominal currents for each section accordingly to the methods of installation and the type of cable either for Cu or Alu. Noting that these values are refered to the standard installation conditions, so, you should know : how the cable will be isntalled, the ambiant temperature around the cable, the number of circuits, then you can calculate the Correction Fcator, by which you can calculate the current of the cable accordingly to the installation conditions.
By the way, there's now a new version of this standard.