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Can a 2 pole breaker be installed in a new NQ panel with a B phase high leg?

Issue:
Can a 2 pole breaker be installed in a new NQ panel with a B phase high leg?

Product Line:
Panelboards

Environment:
NQ

Cause:
Breaker installation in panel

Resolution:
Yes, a 2 pole breaker can be installed into an Old NQOD and New NQ panel with a B phase high leg, if the B phase does not have a rejection screw in it's connector . 240/120 3p/4w B high leg voltage systems will only affect 1 pole branch breakers plugged into the B phase.  The voltage from B phase to Neutral is 208V, normal 1 pole voltage from A/C phases is 120V.  Connecting to B phase with 2 , or 3 pole breakers is fine as long as bussed B phase available for a breaker.

NOTE 

It is highly recommended that in quoting factory assembled NQ High leg Panels ,  to select the remaining pole spaces as 3 pole. If 1 pole spaces are selected , the B phase will automatically come from the Factory with rejection screws in the remaining B phase spaces, thus not allowing for a 2 , or 3 pole breaker to be installed, at a later date.
 

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