Do you do anything special when calculating voltage drop for parallel conductors?? Do you use the resistance for the parallel wire size?? Also, how do you know what the power factor is for a circuit?? Is 85% standard?
If by that phrase you mean taking the resistance of a single conductor, dividing it by the number of parallel conductors, and using that total resistance value in the VD calculation, the answer is ?yes.? On the other hand, if you mean looking up in the tables to find out what conductor type has the same cross sectional area as the combined area of the parallel conductors, then looking up the resistance value for that conductor, then the answer is ?no.?
Ok. So if you were running two parallel conductors the resistance value would be half of what is found in Table 9 of the NEC. Now...how do you know whether or not to use the 85% power factor column or the 100% column?