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What main breaker should be used with a single phase, 225A NQ interior?

Issue:
Main Breaker

Product Line:
Panelboards

Environment:
NQ single phase

Cause:
New or replacement

Resolution:
With main breaker kit NQMB2Q, use a 2-pole Q-frame lug in, lug out breaker.

With main breaker kit NQMBHJ, either a 2-pole or a 3-pole breaker can be used for the higher interrupt H-frames, but if the interrupt is HD or HG, a 3-pole H-frame breaker must be used. This is because the bus links on the outer poles of the adapter kit and the deadfront cutout only work with 3-pole breakers (for higher interrupt values, such as HJ and HL, the 2-pole breaker already uses a 3-pole frame). In this situtaiton, the B phase lug on the breaker can be removed to avoid confusion.

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