Objectionable current

New in the 2002 NEC is Section 630.15 Grounding of Welder Secondary Circuit. The secondary circuit conductors of an arc welder, consisting of the electrode conductor and the work conductor, cannot be considered as premises wiring for the purpose of applying grounding rules in Article 250. FPN: Connecting welder secondary circuits to grounded objects can create parallel paths and can cause objectionable current over equipment grounding conductors. Finally, there is some recognition of what may be considered as “objectionable current.” See 250.6, Objectionable Current over Grounding Conductors.