New with a question about wiring-conduit-labeling

[rcrummett]

Dropped off my permit application for a 20 panel 5Kw system, DIY system here in Northern California.

Have been trying to come up to speed so when the permit is approved I can be competent with the install.

The install will be above my garage ( attached to the house) I want to take the wiring from the panels ( two strings) directly through the roof and run the wire in the attic of the garage, from there down the wall ( inside the wall) to the inverter that will be mounted in a breezeway outside (covered) between the house and the garage. Behind the inverter inside the house is a 125 amp panel that I will tie into. I would like to use conduit only outside... from the panels to the roof penetration, and from the wall to the inverter. These would be short 1-2 foot runs or 90 degrees.

So finally the question.
1.) do I need to use conduit in the attic and in the wall itself?
2.) if so I assume the conduit will need to be labeled in the attic and in the wall ( good luck inspecting this area)
3.) do you recommend a brand name oor box type to penetrate the roof to go from above roof to attic, I don't see one online anywhere for this specific purpose with PV wiring but am sure they exist.

Thanks

[inetdog]

So finally the question.
1.) do I need to use conduit in the attic and in the wall itself?
2.) if so I assume the conduit will need to be labeled in the attic and in the wall ( good luck inspecting this area)
3.) do you recommend a brand name oor box type to penetrate the roof to go from above roof to attic, I don't see one online anywhere for this specific purpose with PV wiring but am sure they exist.

Thanks

1. The wiring inside the attic and wall will need to be in conduit or be a metallic sheathed cable at least as far as the first readily accessible disconnect. See 690.31(E) of the 2011 National Electrical Code for details.
2. All DC wiring inside the building (which includes inside the walls) needs to be labelled every 10' minimum and also have at least one label on each exposed (visible) section of the conduit or cable.
3. Not really. The roof penetration will not be directly via a box, unless you use a "Bell Box" built into the roof and bring the conduit into a threaded opening in the front cover. Not recommended for a lot of reasons. The standard installation will use a roof penetration stack through which the conduit is run and the conduit will then connect to any rainproof box as the splicing point for the wires. That box may also end up being the combiner box if the locations work out. You may also use a watertight elbow or inline conduit body (LB) to join the conduit that comes through the roof to the rest of the conduit.

[rcrummett]

Thank you very helpful advice. I figure it will be more aesthetically pleasing to have the wires and conduit out of site and not draped across the house. And in my case not much more work if any at all.