Audiolabyrinth, as I said the power cord consists of 3 conductors.
Hot - 20 runs of the smaller wire
Neutral - 20 runs of the smaller wire
Ground - 20 runs of the smaller wire
for a total of 60 runs.
You should use 20 in the AWG calculator for number of wires, not 60, to determine the equivalent gauge, as the gauge of the power cord is the size of only one of the conductors, not all 3 of them combined.