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We are located in central Texas. I am needing to run across the road to some type of outdoor distribution panel, as in this image.

enter image description here

I have done some wiring. The power company has already hooked up the electric to the power pole.

In the image where it says in red "This will be about 110 feet." I was thinking about running (3) 2/0 copper wires and a bare ground inside 2" inch conduit. Is that right? What size bare ground?

Cost is a factor. It's either me doing the electric, or candles and NO A/C. Haha.

Of course, I would also torque to specs in the power pole and inside the distribution panel. Am I using the correct term there? (-: We're going to mount the outdoor panel on two treated 4x4's or 4x6's as well in sakrete.

They would like to put my brother-in-law [the RV'er] on some type of electric meter to share costs. Any suggestions?

  • Does it need to be installed like a sub-panel?
  • Does the outdoor panel need it's own copper grounding rod driven into the ground?
  • Does the thick copper ground wire go to the neutral or grounding bus-bar if it's treated like a sub-panel?

We may build a shop on the premises one day, so we'll need 240V.

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    you need to break that down to one question at the time
    – Traveler
    Jan 3, 2023 at 6:14
  • Who's your electric utility? Jan 3, 2023 at 12:49
  • It doesn't really matter who owns or will be living in each unit on the electrical diagram. Strive for conciseness. Jan 3, 2023 at 16:20
  • Ruskes, how, or why would I do that? These are all questions relevant to the topic. ThreePhase, I believe it's Texas Utilities, [TXU] but I would have to ask my in-laws again. Jonathon, conciseness? I know this was wordy when I was typing it out last night, but I was just trying to explain my situation. Dang, I've seen what looks like volumes typed on here before. (-: Anyway, thanks for all your input. Jan 3, 2023 at 18:10
  • @user3051175 -- due to the way Texas deregulated utilities work, we need to know who your in-laws' transmission and distribution provider is Jan 3, 2023 at 23:27

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Saving money on wire.

Almost all transmission lines and service wires in America are aluminum. So are most heavy feeder (like 60A+ type stuff). This has proven totally reliable. Unfortunately in the 1970s there was a copper shortage, and some dimwit said "why don't we shrink this down to 12 AWG and use it for small branch circuits?"

The dimwit forgot 2 important things. First, those heavy wires were going onto lugs actually rated for aluminum wire (and in fact made of aluminum). Second, those lugs are being torqued with a torque wrench. With the small stuff they did neither thing so of course it failed and aluminum got a bad reputation. Now, other nitwits now go "ooh, aluminum bad, I use copper FOR THE SAFTIEZ". And they are simply wrong about heavy feeder.

By the way, another reason to use aluminum is copper at a remote site will be stolen. They are less interested in aluminum. For this reason I also advise direct burial (24" depth) rather than conduit (18" depth, or 6" with RMC/IMC conduit). It's too easy to yank wires out of conduits.

Anyway, assuming 200A service... your correct wire size is 250 kcmil aluminum because it will be serving multiple dwellings. You may also use 3/0 copper if cost is no object.

Ground can be #4 insulated aluminum, or #6 insulated or bare copper. Consult with your permit issuing authority whether they will let you run 3-wire on the "red route" otherwise you'll need ground.

Your temporary drop at the power pole drives up costs a bit.

We can't recommend a model of meter pan, only your power company can tell you which ones they consider acceptable.

Texas is on NEC 2020. As such, the power pole must have a Meter-Main which is a combo meter + main breaker.

From there, you run your 250 kcmil wire + ground wire to your distribution panel 110' away. This panel can be anything that is 200A and NEMA 3R (outdoor) rated. That stuff is cheap, you're not into exotic stuff like "ranch panels". It doesn't even need a main breaker. Yes, you install it like a subpanel. It is a subpanel. Separate neutral and ground. Do the same in the buildings. The only place neutral and ground come together in the whole system is at the meter-main.

I understand you want a temporary hookup for an RV before you bury the 110 feet of cable. How do you do that without wasting equipment? Easy. Buy the distribution panel early, and mount it on the opposite side of the pole from the meter-main* like 2 feet away. Connect it with a few feet of 250 kcmil. Install a 50A breaker and run wire to your NEMA 14-50 type RV outlet.

For the 50A run, Romex or NM is illegal outdoors. If you use UF type cable it must be #6. Any other type of cable (not NM or UF), or wires such as THHN, can be #8 copper or #6 aluminum. "Torque matters" on all sizes of wire - they discovered this on copper, actually.

Once you are done trenching, move the distribution panel to its final location. You can shut off power to the feeder right at the meter-main - aren't meter-mains nice? :)

The final location will need its own grounding rods. 2 rods, unless 1 rod passes a costly impedance test that costs more than another rod lol. Unfortunately, the pole location will as well. In NEC, we slap grounding rods at every structure.

Oh, and build your structures so they can be extended. 12x24 is too small unless it's in downtown Tokyo, London, etc.

If you want a meter for your tenant, then get literally any obsolete meter pan, and an old utility meter for $30 off eBay.

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    Mark this date in your calendars, kids. This is the first time Harper has ever recommended direct burial over conduit!
    – FreeMan
    Jan 3, 2023 at 13:31
  • Do they make a 200A meter-main with a few spaces for breakers? This would avoid the temporary distribution panel setup, and would provide flexibility for other, permanent things near the "power pole" in the diagram. E.g. this. Jan 3, 2023 at 16:28
  • Harper, thanks man. We will probably go with aluminum then. Dang that 3/0 copper is high. LOL. And like I said, they are almost out of money. Actually my mother-in-law and father-in-law are living in the 12x24 cabin about 40 miles away right now. They currently don't have a home, but they're fixing to move it here. The temp line for the RV is already there. My brother-in-law is moving the RV Thursday. But like I said, that's ONLY temporary. He just needed somewhere to plugin. He can't afford RV lot rent anymore. Jonathon, thanks for the link. Jan 3, 2023 at 18:18
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    @JonathonReinhart Yes, those are called combination service entrance device "CSED". It would be important to choose one with load-side feed through lugs. Some Homeline model numbers beginning with SC816 have these lugs (though perhaps not all models in that set do). This avoids the need for the costly "4 breaker slots to 200 amp lugs" HOML2200 lug kit. QO, SIemens, and others of course also make good CSED-with-lugs options.
    – Greg Hill
    Jan 3, 2023 at 19:11
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    @Jonathon Yeah, I call those "Ranch Panels", and they'd do a nice job there - but they also are significantly more expensive so I ignored them. OP could shop around I suppose. Jan 3, 2023 at 20:27

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