Induced Voltages and Power Losses in Single-Conductor Armored Cables

Single-conductor armored cables are often used to carry high currents in buildings. This paper presented an experimental investigation into both induced voltages and cable resistances associated with the installation of these cables within the buildings. Both induced armor voltages and cables resistances under different installation practices were measured at both power frequency and its harmonic frequencies. The impact of cable formation, bonding arrangement and cable supporting method on these issues were addressed, and illustrated experimentally via 185 mm² (365 kcmil) single-conductor armored copper stranded cables. The standing voltage is generally small for the armored cables used in the buildings. Power losses increase significantly when the cable armor is bonded at two cable ends, especially in the case of rich harmonic currents in the cables. Recommendations are finally provided for the installation of single-conductor armored cables in buildings.