Why can the 480V delta system not be used on NF panelboards?

Issue:
480 Vac Delta systems incompatibility with NF panelboards

Product Line:
Panelboards

Environment:
NF panelboards

Cause:
Application, Installation, Rating

Resolution:
The EDB branch breakers used for NF panels have a maximum single pole voltage of 277V. On a 480V delta system, a single pole would see 480V which is more than the branch breakers are rated for.

Released for:Schneider Electric USA