George, I'm aware of the implications of bonding the neutral to ground at multiple points, but it IS legal by NEC in the specific case of multiple derived sources, and absolutely required for make-before-break connections like UPS maintanance bypass switches and paralleling/load-sharing generators where switching the neutral is impossible.
Thus, it is allowed by NEC 250.30(A)(1) in instances like this because there is no way around it. 250.30(A) allows exceptions to this in several other instances, too. Edit- my mistake, I said this was unchanged from 2002, but 250.30(A) is annotated as changed in NEC 2005.
[This message has been edited by SteveFehr (edited 09-28-2006).]
