NEC 2008 210.7(B):
Quote
Multiple Branch Circuits. Where two or more branch circuits supply devices or equipment on the same yoke, a means to simultaneously disconnect the ungrounded conductors supplying those devices shall be provided at the point at which the branch circuits originate.

NEC 2008 408.36(C) [2005 408.36(E)]:
Quote
Delta Breakers. A 3-phase disconnect or overcurrent device shall not be connected to the bus of any panelboard that has less than 3-phase buses. Delta breakers shall not be installed in panelboards.

How can two separate circuits in a 120/240 volt single phase system be attached to a combination duplex receptacle with NEMA 5-XXR and NEMA 6-XXR, with a common handle to meet the simultaneous disconnect rule in 210.7(B) and not violate what appears to be a prohibition in 408.36(C)? Does a 3-pole breaker mean it is a 3-phase disconnect/OCPD? What if 3 separate single pole breakers are tied together with listed handle ties for breakers designed for that, would that make them be a 3-phase disconnect?

Or can this type of receptacle only be connected where the ungrounded conductor of the 120V half is in common with an ungrounded conductor of the 240V half? frown

And what is a "Delta Breaker"? A 3-phase breaker for delta systems? Or does 408.36(C) only apply to delta systems (maybe where the midpoint of one winding is grounded)?

[Linked Image from phil.ipal.org][Linked Image from phil.ipal.org]