Electrical – how to transition conduit through a half-inch OSB shed wall

One trench the whole way will be easier to pull cable through. You could make it direct, one straight line, or closer to it than otherwise.

Fences can get blown over, run into, replaced for service, or removed for aesthetic reasons, which will become more of a pain to deal with if you run conduit along the fence. Also its less pleasurable to look at conduit than to not.

Your municipality or county should be able to tell you your local minimum depth for buried cable. It depends on your jurisdiction if you're asking about code as I assume.

I would recommend oversizing the conduit significantly to make pulling easier and allow for easy upgrades in the future. 2" can't be that much more than 1". It will be more durable and it could save a lot of work later on.

You can save costs on grounding by using bare wire, or using metal conduit as your grounding conductor. But I would not bury metal conduit to avoid dealing with corrosion. Even a bare ground conductor inside a plastic conduit is going to fare worse than a sheathed over time.

Paint a white line where you plan to excavate and call your utility locating service out to mark obstacles. The white line or shape will keep them from needing to mark unnecessary things in far off parts of your yard.

Rent a trencher and make the work easy on yourself.

Bury conduit larger than you need, because excavation sucks.

Dig depth is often 2foot minimum for nonmetallic, 6 inch minimum for metallic, but ask your codes department what they will approve.

For wire gaguge, use a calculator like http://wiresizecalculator.net/.

By my estimate you would want 6awg, but maybe the direct patch can cut down distance and let you use smaller.

Yes, you will either need a subpanel for the shed, or you will need to serve only one circuit of each voltage.

All the receptacles attached to a 30A breaker must be 30A. You cannot hang a bunch of 15 and 20A receptacles off a 30A circuit, except by having the 30A circuit feed a subpanel.

So for instance you could run a single 120V 20A circuit, say, on two 12 or 10 AWG wires. Then a single 240V 30A circuit on 10 or 8 AWG wires, plus one ground wire for all. Those will fit in a 1-1/4 conduit just fine, and be easy to pull. I've pulled 12 12/10AWG wires 100 feet in a 1" conduit and that was easy.

Or you could run four 10 or 8 AWG wires and serve off the 30A breaker to a subpanel. The subpanel can be any size (larger then 30A obviously). It will need to have a main breaker in it, because you need a local shutoff switch and that's the easiest way to do it. You will need to keep ground and neutral separate inside the subpanel, and add a local grounding rod at the shed. I myself would run 4 AWG Aluminum because it will leave lots of headroom to 50A, and the lugs on the panels are aluminum anyway.

Also I'd get a fairly big panel. Panel space is cheap, I'd go at least 20. Some of them even throw in free breakers.

Adding an Image of Sub Panel Service Diagram with notes.. Borrowed from here > Link