Electricity to Barn (350 ft)

SOS · Dec 31, 2011

I need about 60 amps at my barn which is about 350 feet from the house panel. It must be buried and it will cross over my cable for the tv.

I looked at running a new line from the street but they want $65 a month for the meter which is too high.

I've received quotes and they are all over the place. Can I get your opinions on these?

1. $5.5K -- 2 6/3 wires from panel in house to outside wall then 1/0 Aluminum to barn (about 290 ft).

2. $4-K -- 1 6/3 copper wire from pannel to house outside wall and then 1/0 Aluminum to barn.

3. $1.5 -- 1 10 guage wire all the way to the barn.

4. $3-K - 1 6/3 copper wire all the way from the panel to the barn.

These all are official quotes from companies in my area. What do you think?

:confused2:

Bigfoot62 · Dec 31, 2011

I'm not an electrician. I just do my own electrical work.

So, my opinion, plus $1.00, will get you half a cup of coffee in some places.

Are you sure on the $65 per month? Here, you can get a second meter for your shop or barn, and it costs about $12 per month minimum. I would suggest the separate meter, if it's feasible.

IIRC, the voltage drop per 100' is about 10 amps.
In other words, option #3 wouldn't work. You would only have 60 amps (30 amps per leg on a 10/3 cable) for 100'. Beyond that, voltage drop would eat up your amperage to the point that you would probably burn up an electric motor at 350'. (like a 5hp air compressor)
I think that you would need the 6/3 at least, maybe a 4/3 to carry that kind of load.

Depmandog · Dec 31, 2011

If you were to rent a trencher, plus do the backfill yourself, it would be interesting to see how much your quotes drop.

Here electric is buried a minimum of 18" deep. Pretty easy dig for a trencher. Little bit of hand digging at the house, barn and around your cable tv. Call your locate service (here it is Dig Rite) and they will mark the location of the cable.

As far as the electric wire, I agree the 10 gauge it not an option. I too would call the electric company and double check the pricing. My monthly bill for my building with outside lighting is 15-25 per month, depending on how much I use the building.

Good luck

Dean

tommu56 · Dec 31, 2011

SOS said:
I need about 60 amps at my barn which is about 350 feet from the house panel. It must be buried and it will cross over my cable for the tv.

I looked at running a new line from the street but they want $65 a month for the meter which is too high.

I've received quotes and they are all over the place. Can I get your opinions on these?

1. $5.5K -- 2 6/3 wires from panel in house to outside wall then 1/0 Aluminum to barn (about 290 ft).

3.4% voltage drop = ok for the 1/0 the 2 6/3 wires don't make any sense you need 4 wires for sub panel in my area.

2. $4-K -- 1 6/3 copper wire from pannel to house outside wall and then 1/0 Aluminum to barn.

3.4% voltage drop = ok for the 1/0 the 1 6/3 wires don't make any sense either you need 4 wires for sub panel in my area.

3. $1.5 -- 1 10 guage wire all the way to the barn.

16.2 % way too much loss and 10 gauge is rated at 30 amps how are you going to get 60 through it?

4. $3-K - 1 6/3 copper wire all the way from the panel to the barn.

6.6% drop ok but not good design and a little light rated at 55 amps so marginal for 60 amps

voltage calculator

:confused2:

By the chart 2 gauge copper would be the correct size if I were running it.

That would be 3 #2 (hot, hot , neutral) and #6 ground cooper and a driven rod at the barn again done to code in my area.

You could substitute aluminum conductors 1/0 If you were doing that I'd just run aluminum all the way not change to copper unless you cant get a connection on your panel for 1/0.

tom

BMod · Dec 31, 2011

tommu56 said:
By the chart 2 gauge copper would be the correct size if I were running it.

That would be 3 #2 (hot, hot , neutral) and #6 ground cooper and a driven rod at the barn again done to code in my area.

You could substitute aluminum conductors 1/0 If you were doing that I'd just run aluminum all the way not change to copper unless you cant get a connection on your panel for 1/0.

tom

X2, Tom is correct, but the prices seem high for a days work for two guys.......

Carl_NH · Dec 31, 2011

6-2 is about $2.50/ft or 6-3 UF copper is now $3.50/ft so you are looking at $1000-1500 of wire so the $3K bid for 350' of 6-3 is pretty decent if that is the installed price. You will not get a full 60 amps due to line loss so it depends on what you are planning to run in the barn - like for a welder or heavy use I would go bigger..

Around here a separate meter and entrance setup is probably $800 or so for the install, then monthly base rate is $20 plus electricity so $250/year service fee - my average bill for a separate entrance is $35 / month for 200KWH.

For the long term the feed off the house would be most cost effective, but if you intend to expand or need more power in the barn in the future then the best solution would be a separate feed/entrance.

lhfarm · Dec 31, 2011

Here is the story of my barn run from a couple of years ago -
http://www.tractorbynet.com/forums/projects/139326-450-wiring-conduit-how-assemble.html

The power company gave me good advice and I'm glad I went with the bigger service. I can run a welder there if I ever need to do so.

Good luck!

grsthegreat · Dec 31, 2011

Ok, heres the figures as i calculate them. For a 4.8% voltage drop over 350 foot run you are going to use #2 alum URD direct burial wire buried 24" below the ground (or 18" if buried in conduit). Whoever gave you a quote on #10 is an idiot. at 350 feet you couldnt even get 15 amps out of that.

We run #2 all the time and there had never been an issue with its use. You can even run a 2/2/2/4 SER cable under the house if you wish to a J-box where it leaves the house and starts the path underground. You need to run 2 hots, one neutral and one ground wire to the shop.

2/2/4 URd runs about $1.50/foot here in Idaho, plus $0.35 / ft for the #6 ground wire.

i always run at least 1-1/2" conduit on my work with #2 wires, and this is running about $0.50/foot

then theres labor... who digs the tranch.

also remember the panel in the barn.

personally for my company id be charging about $2,000 jusdt for the 350 foot run of conduit, wire, trenching, labor to install and cover

then theres the labor/material to get to the house panel (not sure whats involved) and the barn panel (not sure whats involved).

hope this helps

Craig Clayton · Dec 31, 2011

I am in the trade but I do not do Under Ground side jobs. So I will not wade into the quotes.

As far as the minimum depth of burial that means ( how close is it to the surface ). There is nothing in the code that stops you from putting it down deeper within reason.

The reason I say this is lets say in 5 years the trench has all grassed smooth and you want to plant a tree or shrubs and you have forgotten where the wires are. If you have the code strip of plastic marker tape buried with the cable.
What it really means is you just dug or nicked your UG conductors.
Resi contractors do not really worry about your depth if you nick it then its extra $$.

Depending on the methods of your area 4" Big O or 2" or 3" Ridgid PVC as a conduit.
This will protect the conductors for a life time.

I put my house supply service in 2" poly pipe and my 60 Amp service to the barn in 1" Ridgid PVC. Phone lines in 3/4" Ridgid PVC were buried 6" above the 120/240 VAC. Why not not add a water line in the trench 3/4" poly at the same height as the phone line.

Craig Clayton

grsthegreat · Dec 31, 2011

Also, to run a 6/3 COPPER all the 350 foot to the barn would result in a 8 - 9% voltage drop. So whoever suggested this is also nuts. This is WAY outside the allowable 6%, I always try to stay in the 3-4% on all my outbuildings.

Voltage drop plays havoc on equipment.