Table for resistance for NM-B inverter output conductor

[SolarAlternativesDesign]

What NEC table is best for calculating voltage drop for ac power for inverter output in an NM-B cable not in conduit? Table 9 Chapter 9 shows resistance and reactance values for ac circuits in conduit (allowing 3 choices for type of conduit material), but the NM-B conductors would not be in conduit. Table 8 Chapter 9 shows resistance for dc circuits and does not require specifying a conduit. The results would be very similar for most conductor sizes, but I would like to use the correct method.
If using Table 9 Chapter 9 for ac voltage drop for a PV inverter output circuit, is it correct to assume reactance = 0 and use only the resistance?

 

[don_resqcapt19]

Use the first column...the one for PVC and aluminum conduits.

 

[Carultch]

What NEC table is best for calculating voltage drop for ac power for inverter output in an NM-B cable not in conduit? Table 9 Chapter 9 shows resistance and reactance values for ac circuits in conduit (allowing 3 choices for type of conduit material), but the NM-B conductors would not be in conduit. Table 8 Chapter 9 shows resistance for dc circuits and does not require specifying a conduit. The results would be very similar for most conductor sizes, but I would like to use the correct method.
If using Table 9 Chapter 9 for ac voltage drop for a PV inverter output circuit, is it correct to assume reactance = 0 and use only the resistance?

The difference between "AC resistance" and "DC resistance" is negligible for conductors that are smaller than 1/0. So Chapter 9 Table 8, or any of the columns in Chapter 9 Table 9 will work for this size.

Essentially, the reason for the different columns, is to keep track of the effects of the ferrous conduit being magnetized, and increasing the inductive effects. NM cable has exactly the same magnetism physics of PVC conduit. No ferromagnetic material anywhere within the feeder assembly.

 

[SolarAlternativesDesign]

I see. Thanks for the explanation.