Question regarding cables

bart
bart Solar Expert Posts: 30
I want to ask you a few questions regarding the wiring as it's outlined in the permit.

The permit design show cables from the combiner box to the array the cable is 6 # 10USE2 in a 3/4 EMT conduit. I assume I was to mount the combiner box at the top of the roof next to the array. And from the Combiner to the DC cutoff it should be 6 # 10THWN-2 in 3/4 EMT conduit.

The supplier sent me 6 cables with doubled ended MC4 connectors at 30 and 50 feet in length. They also supplied a Midnight Solar combiner box with 3 Breakers. So it appears they were thinking of mounting the combiner (with breakers) below next to the DC cutoff by the inverter. The cables are long enough to reach from the array to inverter so it kind of make sense to mount the combiner/breaker box next to the inverter.

My questions:

1. Am I allow to run 6 cables in an EMT conduit from the roof array directly to the combiner box if the cable are USE-2 10 AWG instead of the 6 # 10THWN-2?
2. If so, how large should the EMT be to enclose the 6 USE-2 10 AWG cables?
3. If I do this, do I need to change the permit?
4. Is the ground wire (#6) ran inside the same conduit as the 6 SE-2 10 AWG cables?

Does this make sense?

Thanks, Bart