How can two back fed circuit breakers be retained in a QO load center?

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Issue:
Load center has two back fed breakers that need to be retained.

Product Line:
QO Load Centers

Resolution:
Two 2 pole breakers can be retained in Series S01 and S02 single phase QO Load centers. (Not available for Homeline)
This is done by using the Manual Transfer kit for the appropriate ampere rating, and not using the included QO2DTI interlock.
The table below outlines the choices;

Load Center Type	Amperage Range	Series	Side of Panel	Position (in Panel)	Part Number
QO	100A-125A	S01, S02	Right	2,4,6,8	PK4DTIM4LA
QO	150A-225A	S01, S02	Right	2,4,6,8	PK4DTIM4HA
QO	100-125A	S01, S02	Left	1,3,5,7	PK4DTIMLAL

In many cases this is requested when a load center is being used in a PV system to combine inverter outputs.
If the inverters are considered "Utility Interactive" then under the 2011 NEC, section 705.12(D)(6), a retaining kit is not required.
This is because the inverter will shut down when it no longer senses the utility side connection.