Wiring house & shop

[radios1]

you need at least #3 gauge for 100 amps, but that's at a maximum of 100 feet!. you need to go up one size larger wire for each 100 feet!.. at 470 feet, you need to go up at least 4 times the needed gauge, to prevent problems with wire heating and voltage drop!. unless, your power company will put a primary to secondary transformer near your intended shop!.. #2/0 wire.. "1 conductors per phase utilizing a #2/0 Copper conductor will limit the voltage drop to 4.26% or less when supplying 100.0 amps for 470 feet on a 240 volt system.
For Engineering Information Only:
175.0 Amps Rated ampacity of selected conductor
0.1 Ohms Resistance (Ohms per 1000 feet)
0.043 Ohms Reactance (Ohms per 1000 feet)
12.0 volts maximum allowable voltage drop at 5%
10.222. Actual voltage drop loss at 4.26% for the circuit
0.9 Power Factor
**Note to User:All ampacity values are taken from the Section of 310-15 of the NEC. The conductor characteristics are taken from Table 9 of the NEC. The calculations used to determine the recommended conductor sizes for branch circuits are based on 60°C ampacity ratings for circuits rated 100 amps or less or marked for use with #14 AWG - #1 AWG. Circuits rated over 100 amps or marked for conductors larger than #1 AWG are determined using 75°C ampacity ratings. Calculations to determine service and feeder conductor sizes are based on overcurrent device ratings rather than actual expected loads which are conservative and may yield oversized conductors. No calculations take into account temperature correction factors or conductor de-rating.
This voltage drop calculator is applicable only to NEC applications. It does not optimize conductor sizes for several different loads at various points in a circuit. The total combined load and length of the circuit must be used. Consult with an engineer if your application requires more complex engineering calculations. " Voltage Drop Calculator

 

[buickanddeere]

Overhead high tension to a transformer in the yard. Transfer switch for a generator right there. 200amp doesn't cost any extra and you will hate yourself for being cheap afterwards. All underground 120/240V to all buildings .
If you can't afford to do it right, don't do it at all.

 

[buickanddeere]

I believe you need to start by talking to the power company. They will offer suggestions, solutions and variables based on your location and costs. We may suggest methods that your power company will not do.

I'm in the midst of a build now. The power company went underground from the powerline to my site, 350ft. There they set a 400A transformer pad and meter setter. The setter contains two 200A disconnects. That cost me $1250.

My shop and house are close together with the meter setting sort of between them at the backside. Buildings are only 50ft apart.

I buried 4O wire in 2" plastic conduit using long sweep elbows to the shop. The shop has an outside conduit and elbow up about 6ft thru the wall into the back of the main breaker box. It's a 200A. The wire was expensive at $1.15 per foot times 3.

The house uses the same size/type of wire and conduit. Difference is it stays underground into the house.

This worked great for me. Was cost effective. Clean installation with no overhead to worry about. Both buildings on one meter.

Curious why you want your two buildings so far apart?

My current homestead has the two buildings 200ft apart. That's a hard trek in the dark when it's raining or snowing. I vowed this time to make it easier. I'm 67. When I'm an old man I want easy.

You missed the ground wires that join all electrical service box/breaker box ground lugs together to the same potential. Double ground rods at the meter base and at each breaker panel.

 

[ovrszd]

You missed the ground wires that join all electrical service box/breaker box ground lugs together to the same potential. Double ground rods at the meter base and at each breaker panel.

I didn't realize I needed to be that detailed.

 

[Corkpuller]

Here's a pic of my transformer, meter setter in case you aren't familiar with them.



View attachment 582029

No rush, but if you get a chance, I'd like to see the inside of your service box.
I assume it's 2 sets of lugs off one side of the Meter to allow for 2 separate 200A services.

This is exactly what I'll be faced with next Spring.
Will be building the Shop before the house.

And, for the OP, the cost to run the Primary from the road across private property to your Meter will vary big time from one area of the Country to the other.
I am on a Co-Op ....... to run overhead Primary it's $2 a foot. Underground is $5.25 a foot. And that my friend is CHEAP.
I'm lookin at needing them to bring in about 600' of Primary.
Closer to the "big city" with a different Electric Utility that cost for just overhead could be 5X that much or more.

 

[LouNY]

There have been several good suggestions so far;
I'm not sure if I would go with a 400 Amp service or just a 200 Amp with your projected usage it would depend on the cost.
I'm thinking AL. with trees,
I would bring the main in as a buried high voltage to a transformer between my two buildings,
I would have a transfer switch at that location rated for the full load and a main panel with my two or 3 sub feeds so I could have generator feed to either or both locations and I would have all buried deeply in conduit.
Just my way of thinking.

 

[ovrszd]

No rush, but if you get a chance, I'd like to see the inside of your service box.
I assume it's 2 sets of lugs off one side of the Meter to allow for 2 separate 200A services.

This is exactly what I'll be faced with next Spring.
Will be building the Shop before the house.

And, for the OP, the cost to run the Primary from the road across private property to your Meter will vary big time from one area of the Country to the other.
I am on a Co-Op ....... to run overhead Primary it's $2 a foot. Underground is $5.25 a foot. And that my friend is CHEAP.
I'm lookin at needing them to bring in about 600' of Primary.
Closer to the "big city" with a different Electric Utility that cost for just overhead could be 5X that much or more.

I'll try to remember to get a pic tomorrow. Yep two disconnects side by side.

 

[RBA50]

If you have an electrician in mind you can run it past him. If he has worked in the area for a while he will have a good idea of what the Power company will allow, as well as suggestions on the most cost effective methods.

 

[NTG]

So I guess I'll approach the power company. I didn't know if it mattered if I went to the shop and then the house or the house and then the shop. I'm locating the buildings on the property based on road layout, physical lay of the land and based on where many other things will be located. My ignorance of electrical service may have introduced unseen problems here. Some days I feel like chucking the whole thing anyway. I appreciate everyone's advice. I'll try to get with the power company and report back what I find out.

 

[mikester]

Go above ground to a pole at the barn. Then go underground to your house. Cheap and easy. And upgradable. Id recommend 200A each drop. You arent saving anything in the long run if you cheap out now and you will regret not putting in 200A when you had the chance.

Do you get ice and wind storms? Clear out the trees around the above ground portion up front. Stuff grows back faster than you will expect.