Here is a very devisive issue - if several EGCs enter a distribution panel [or service panel], can you connect two or more of them together and pigtail a properly sized conductor to the EGC terminal bus? (e.g. 3 #12s enter the panel, you connect them together and run a #12 pigtail to the terminal).
The 2002 HEC Handbook 'commentary' for 250.122(C) says: "It [the EGC] is not required to be sized for the 'composite' of all the circuits in the raceway because it is not anticipated that all circuits will develop faults at the same time." - yes, this is a commentary on properly sizing the EGC in a j-box or conduit.
At issue: If you can size a single EGC to protect several circuits in a raceway or j-box, can you not do the same thing in the panel?
384-20 speaks of the requiring the grounding of panelboards, but it does not specifically address this question and I know of no other code section that does address this specifically.
The current language of 384-20 came into the code in 1990 and the 1990 NEC Handbook does not speak directly of this issue either.
BTW - this is NOT a practice I condone or support; however it is one of those 'code issues' I would like a clear and concise answer to. Opinions are great (mine is - don't do it), but the question is: Is there a particular code section prohibiting this practice?
Anyone have copies of the ROPs/ROCs for the 1990 code cycle?
