I installed a sub-panel in our garage/barn. 100 amps. Put 2-2-2-4 mobile home service cable in 2 inch conduit. Now I would like to connect my backup generator at the barn instead of the house. (outside) I have an interlock on the main panel, so would need to run #10 wire (for 30 amps) between the generator input plug box (to be moved to the barn) and the main panel. About 70 feet. Here's the question--can I run the wire from the barn to the main panel in the 2" conduit which feeds the sub-panel. Of course, the #10 wire from the main panel would have no connection in the sub-panel. I just would like to use the conduit. Thanks.