Hi Paul (great name [Linked Image] ),

I think part of the problem lies with the strict definition of a neutral conductor versus the casual use of the term in everyday speech (it being shorter to say every time than "grounded conductor").

What if we have a 2-wire 120V branch circuit running from a normal 120/240V 3-wire service? The white wire on that branch circuit is not in itself a neutral by the strict definition, but it is connected to the neutral at the panel, and the current flowing on that branch circuit meets up with the neutral at that point.

In fact here in Britain the grounded conductor of a simple 2-wire circuit has been defined as a neutral by the I.E.E. for many years. Here's their definition from an old code book (although the first part referring to a 3-ph 4-w system is badly worded with its circular reference):

Quote
Neutral conductor. The neutral conductor of a 3-phase 4-wire system, the conductor of a single-phase or d.c. installation which is earthed by the supply undertaking (or otherwise at the source of supply), or the middle wire or common return conductor of a 3-wire d.c. or 3-wire single-phase a.c. system.