I am installing an electrical subpanel in my garage and have a 2" PVC conduit run up approximately 5 feet from the panel through the ceiling to the garage attic. In the conduit i ran 2 12/2 NM romex runs for 2 separate circuits.
The AHJ said that this is not permitted and that i would need to run individual wires. I plan on installing a junction box on the top of the conduit where i will make the connections between the NM cabling and the individual THHN wires i am running into the subpanel. My question is do i need to fasten the THHN cables in the junction box? The NM cables will have the plastic insert in the knockout. If it does need to be fastened, any ideas how? I could drill holes in the jbox and use strap ties but don't think that meets code.