loop impedance

The term loop impedance refers to a connection loop consisting of a forward and return line.

As with any other conductor, the loop impedance depends on the resistivity or electrical conductivity of the conductors. It is therefore dependent on the conductor cross-section, the temperature and the loop length. For reasons of better handling and comparability, the resistance given in ohms refers to a distance of one kilometer. For stranded symmetrical cables, the actual conductor length is longer than the cable length, due to the stranding.

For example, the loop resistance for a wire size of AWG 24 and a conductor cross-section of 0.511 is 173.8 ohms per kilometer.