One answer would be no, this isn't allowed. 310.15 (B)(7) says it is allowable for the main feeder conductors and further states that the main feeder conductors are installed between the main disconnect and the panelboard that supplies ... Since there is no connection of the generator to the main disconnect, this isn't the main feeder, nor are these service entrance conductors.The commentary in the handbook explains that the conductors must carry 100% of the diversified load, which these conductors will carry.However, the last part of the section says that feeder conductors to a dwelling unit (it does not say main feeder conductors) shall not be required to be larger than their service entrance conductors. So, if this is a 100 amp service, I believe it should be allowable to use #2 Aluminum conductors.

- Chris Donell (St. Matthews, KY), 03/25/2017

Harold:Splitting hairs by using the feeders shall not be required to be larger than the service entrance conductors would allow this, but I feel the amperage rating of 310.16 table, 75degree col should dule here. And IF the 'rehab' card is pulled, '05 NEC prevails with no change to the forementioned. (My two cents)

- Bexar Air (Maine, ND), 03/25/2017

I would only let them use 310.15(B)(6) if it was sized to the service capacity, not the generator.If this is a house running on 100a from the utility, then it could use 100a to size the generator feeder.I am still a little uncomfortable with 310.15(B)(6) when people continue to load up a service after the initial installation until they are actually cruising at close to 80% a good part of the time and tripping the breaker occasionally.

- Tyrone Mccarthy (Amherst, MA), 03/25/2017