Table 8 for 250.122(B)

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Flapjack

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Does Chapter 9, Table 8 have to be used for calculating the new EGC size 250.122(B)? I am thinking not as it is in the handbook commentary and not in 250.122(B) itself.

I'm calling out for a medium voltage 1/0 AWG cable, but the minimum size for the circuit is 4 AWG w/ 8 AWG EGC. Using Chapter 9, Table 8, I get 41769 mils which is 29 mils above 4 AWG EGC. If I use the table on the engineering toolbox site, I get 41,739 mils. If I calculate the mils of the 1/0 AWG cable from the specified manufacturer, it's even less than published 1/0 AWG circular mils values in the two tables (NEC and engineering toolbox).
 
In my opinion, the values in the Chapter 9 tables are the official values and must be used for your calculations.
 
250.190(C)(3) says that equipment grounding conductors shall be sized in accordance with Table 250.122. I don't see any requirement to comply with section 250.122(B).

However, the note in Table 250.122 may require a larger EGC.
 
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