Article 311 - Medium voltage conductors and Cable

[Tim Davies]

A few questions regarding Article 311.
1. When sizing MV cables for Ampacity is the 125% rule in 310 applicable
2. What is the basis of table 311.12(A)

regards

 

[ron]

I'm guessing you are looking at the 2020 NEC since the 2023 NEC renumbered MV to 315.

310 does not influence 311 unless specifically called out such as for conductors in parallel.
Table 311.12(A) identifies the minimum conductor size. I've always understood it was that way because the manufacturers were not making anything smaller at those voltages.