After 55 years with only generator power at our cottage, we're going to have a 100Amp 240V service added to our property. I have a 6-circuit generator transfer switch available, but do not plan to use it unless we decide to keep the generator in the configuration long term. We may just use the generator as a standalone system for outages only without connecting it back into the power distribution system. (The island has 3 wind turbines and a set of diesel backup generators.)

The shed where the generator is attached has always been the main panel, and the cottage has been a 120V only sub panel with floating neutral and bridged hot legs. I have converted the shed panel to simply be an outlet at the and of the 10 gauge line that formerly fed the cottage, and moved it to breaker #8 in the cottage panel. The cottage panel has been changed back to 240V.

I'm mounting the mast and CQRB100CP meter base/main disconnect panel with ground rod on the outside of the wall right behind the current TL412CP cottage panel. My current thinking is to run aluminum 2-2-2 SEU cable from the mast head in 2" conduit down to the meter base, and continue it to feed the 100Amp main breaker panel. Also thinking to run copper 3-3-3-5 SER from the main breaker to the cottage distribution sub panel.

Do these wiring sizes sound correct for my application?