The conductor resistance is the ohmic resistance of a conductor and is directly dependent on the conductor material, the conductor cross-section and the conductor length. The resistance increases with longer conductors and decreases with larger conductor cross-sections. The conductor resistance (R) is given in ohms or milli-ohms.
The conductor resistance of a conductor is largely determined by the conductor material, with copper and silver having the lowest resistivity. The resistance of a conductor is calculated from the conductor length in meters, the specific resistance (Rho) and the conductor cross-section. The conductor length is proportional, the conductor cross-section inversely proportional.
For copper lines in telephone technology and cabling, there are internationally valid standard values for the copper quality and the conductor cross-section, which is calculated from the standard diameters of 0.5 mm and 0.6 mm. For the most commonly used conductor diameters of 0.5 mm and 0.6 mm, the conductor resistances are approximately 23 ohms and 16 ohms.
The conductor resistance is an important parameter for the attenuation of the line, because it significantly determines the range of transmission. Instead of the conductor resistance, the loop resistance is often specified in specifications. This refers to a conductor loop consisting of a forward and return conductor of one kilometer. To keep power losses as low as possible during energy transmission, high-temperature superconductors and conductors with the lowest conductor resistances and extremely low impedance, Very Low Impedance (VLI), are used.