Burying AC, solar DC and ethernet cable

Question

I am building a pole barn about 200 feet from my house.  I would like to run 90amp or so 240VAC to a subpanel, as well as ~400VDC from solar panels, and a pull or perhaps two of Cat5e ethernet cable.
The 240VAC will go to a subpanel in the pole barn, and will be 4 conductor (L1, L2, N and G). The subpanel will also be tied to a ground rod at the pole barn.
The 400VDC will likely be 3 pair, and will go from solar panels to inverters at the house, which tie into an existing grid connected solar system.
The ethernet will have two runs, mostly for redundancy.  I only need one.  I have considered running more, but a better solution might be to put a POE switch in the barn, and use POE to run cameras.
Each group of lines would run in their own conduit.  I will try to keep the ethernet conduit away from the others in the trench.
I am considering using aluminum wire for the 240VAC and the solar, for cost.  I would probably want to try to go with copper for the solar, since it would frequently cycle between maximum power and no power more often than the 240VAC.
Is 10" suitable separation for the Cat5e? Any other suggestions?

Ecnerwal · Answer

For networking, use fiber optics, or point-to-point wireless.
By the time you provide adequate lightning suppression (UL497 Primary Protection) on copper ethernet, fiber is likely cheaper, and it's definitely more robust. I've never replaced a fiber for a nearby strike, but it's not uncommon to need to replace surge protectors after a storm.
If there's a clear shot, point to point wireless also works well, and may feel more accessible (fiber is not all that difficult, but it can feel daunting to get started with.)
There's really no advantage to using copper wires .vs. appropriately sized aluminum wires for the other two circuits. A thing you might want to consider would be skipping the DC circuit entirely by putting an inverter at the barn.

Burying AC, solar DC and ethernet cable

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