| Abstract Scope |
Stranded metal wires are used for electrical connections. The inductance contributes to the impedance, but the inductance of stranded wires has not been previously reported. The stranded wire (commercial) consists of tin-coated copper strands of diameter 0.08 mm, with the number of strands N ranging from 252 to 5,000. The apparent single-strand inductance calculated from the measured stranded wire inductance by assuming that the strands were exactly inductors in parallel reaches 6.27 mH/m, compared to the measured single-strand inductance of 1.9 µH/m. The large ratio of the apparent to measured single-strand inductance (reaching 3,300) is linearly related to N. Thus, the strand-strand contacts govern the inductance. Both inductance and resistance decrease with increasing N, with the fractional decrease in the inductance being much less than that in the resistance. The inductance does not obey the model of inductors in parallel, due to the strand-strand contacts, whereas the resistance essentially does. |