I have the 2011 NEC Code book but I noticed that the NEC 2002 referred to the word "Secondary" in article Tap Rules 240.21(c)(2). Why isn't there a NEC definition for "Secondary"? Was or is there a definition?
I think the word 'secondary' has only been used in the term 'transformer secondary conductors', which is pretty self-explanatory. I just quickly searched for "secondary conductors" in a PDF of the NEC and cant spot any references that are not clearly related to a transformer.