Cable conductor sizes

The full range of IEC and AWG conductor sizes and corresponding standard DC resistance values is supported.

Posted 2016-01-07
Categories: New feature, Theory

The range of conductor sizes together with the relevant DC resistance of conductor at 20°C has been enlarged last November to cover all relevant IEC sizes between 0.5 mm2 and 3000 mm2 and all relevant American wire gauges from 26 AWG up to 5000 kcmil.

All conductor construction types together with the corresponding resistance value according to IEC 60228 Ed. 3.0 are supported:

  • Class 1: Round solid, plain or metal-coated copper or aluminium
  • Class 2: Round stranded, plain or metal-coated copper or aluminium
  • Class 5: Round stranded flexible copper conductors
  • Class 6: Round stranded more flexible copper conductors
  • Milliken conductors: with bare uni- or bi-directional or insulated copper wires or with aluminium wires
  • Sector-shaped conductors: plain and metal-coated copper or aluminium

The resistance value for 3000 mm2 has been calculated as no standard value is available.

The resistance values for the AWG conductor sizes have been chosen in accordance to the new draft standard IEC 62602 'Conductors of insulated cables – Standard for AWG and kcmil sizes' from October 2015, which is a working document from the IEC technical committee 20.

  • Class 1: UL 1581 Table 30.1 and 30.2
  • Class 2: UL 1581 Table 30.3 and 30.4 Class B
  • Class 5: UL 1581 Table 30.7 ASTM Class G (14 AWG-10 AWG) and Table 30.8 ASTM Class H (8 AWG-1250 kcmil)
  • Class 6: UL 1581 Table 30.11 ASTM Class M
All relevant American wire gauges between 26 AWG and 2000 kcmil are according to the corresponding table in the UL 1581 as listed above. For copper conductors with sizes between 2250 and 5000 kcmil, they are based on ASTM B8-11. And for aluminium conductors between 2250 and 4000 kcmil, they are based on ASTM B231-04. For aluminium conductors between above, the values have been calculated to $Ω/m$ at 20°C from the values in $Ω/ft$ at 25°C given in the book 'Electrical Power Cable Engineering' by William A. Thue, 1999.

The user may select copper or aluminium for conductor material or define his own conductor material by entering the specific electrical resistivity $ρ_c$ at 20°C and the temperature coefficient $α_c$ per K at 20°C.

Depending on the conductor material (copper or aluminium), the construction type, the wire type and the insulation material, the factor for proximity effect coefficient $k_p$ and the skin effect coefficient $k_s$ is selected. Both values can also be entered manually by the user.