Article 240 provides the requirements for overcurrent protection. Part I of this Article provides the usual scope, definitions, and “other Articles” information (240.1, 240.2, and 240.3, respectively) then it gets into protection of conductors in Sec. 240.4.
Section 240.4 does not cover flexible cords, cables, and fixture wires; those are covered in Sec. 240.5. Nor does it cover ungrounded conductors; those are covered in Sec. 240.15. So what exactly doe