Another electric service to barn question

lhfarm · Dec 6, 2007

I've read most of the threads here. My barn is ~430 feet from my garage/workshop service entry/panel. The garage has 200 amp service and that is where I have my welder, compressor and work tools. The barn needs lights, power to run my block heater and the occasional power tool. I did think I should plan for taking my stick ac/dc welder (on a 50 amp circuit in the garage) there for the occasional repair.

I called a local elecrical contractor and he just gave me a bid for wire, 100 amp panel in barn and installation of breaker in garage box.
- for #2 $1400
- for 2/0 $1900
To put the wire in the ground is an additional $500. I told him I had a BH, but I think he wants to send some work to his digger.

I'll add that neither the garage or barn are finished, so working on the panels isn't hard. We don't need an inspection. Some questions:
1. Do his numbers seem really high?
2. Would 2-2-2-4 AL dropped to 75 amp work (I used the voltage drop calculator and I think it would work to run my welder)?
3. If I follow this plan http://www.tractorbynet.com/forums/...1d1180903741-electric-service-barn-wiring.jpg, any reason I shouldn't do this myself?
4. He was going to plow the wire in. I was thinking 3' deep and in conduit. Is he right?

Thanks,

Rara Avis · Dec 6, 2007

Copper is thru the roof...

$1,000,000 in sculptures stolen for their $100,000 copper value...

Million Dollar Sculptures Stolen

kenmac · Dec 6, 2007

I ran my electrical( to my garage) myself & put it under ground in 2"conduit. I used 2/0 alum. wire. My friend works for local power co. & got me the wire for 0 $ I paid for the conduit. this is the same type wire the power co. uses for service to the houses. I had to get inspection. Had another friend pull permit for 0 $

I forgot to add, that from my breaker box inside the house I ran copper wire until I got outside the house & then I tied the copper to the alum. wire with alum. to copper connectors in a junction box. The alum. wire inside the house wouldn't have been to code

hockeypuck · Dec 6, 2007

I would put the 2" conduit in the ground and pull three wires, 2-2-4 aluminum and put a 75 amp breaker on it. You do not need four wires. Drive two ground rods out at your barn. If you have the 2" pipe in the ground you could pull 2/0's in the future if you needed to. Do not let your electrician direct bury the wire. That is bad news.

WVBill · Dec 7, 2007

Your run is a lot longer than the run I had from the house to the barn I built (mine was 165 feet) but I used the circuit diagram you showed and used #2 copper off a 60 amp dual pole breaker in the main panel (2 hot, 1 neutral plus ground). Buried about 18" in 1" conduit.
Did it myself. Passed inspection.

You could go 24" deep with direct burial SE cable and be to code.

You have the tool for the trench. If you feel confident with the wiring, I say DIY and save the $$.

1" conduit would be real tight for a 400'-plus pull of either #2 or 2-0 - - go with the 2". You can also lay the cable out and slip the conduit down the cable one piece at a time. Though I understand this is not a "best practice" it's the way I did mine.

WVBill

McRancher · Dec 7, 2007

I just finished running power from the house to the barn. I dug the trench with a rental ditch witch, and did as much of the easy part as I could, then my neighbor who is an electrician came over and did the hook ups. Wire, switches, lights and ditch with rental was about $600.

turbo36 · Dec 7, 2007

hockeypuck said:
I would put the 2" conduit in the ground and pull three wires, 2-2-4 aluminum and put a 75 amp breaker on it. You do not need four wires. Drive two ground rods out at your barn. If you have the 2" pipe in the ground you could pull 2/0's in the future if you needed to. Do not let your electrician direct bury the wire. That is bad news.

In most places this would not meet code because of the lack of a ground to the main panel this is not a good idea. Also at this length the voltage drop for aluminum wire would exceed 10%! Recommended max voltage drop is 5% or less preferably 3% if you run a lot of motors (air compressor, table saw, etc,)

3 years ago I did the same project except my barn was 460' away, I went with 2/0 copper ( 2 hots, 1 neutral and a ground) direct bury and I am happy I went the extra because I added equipment and didn't have to worry about capacity.
Do it once, do it right.

techman · Dec 8, 2007

turbo36 said:
In most places this would not meet code because of the lack of a ground to the main panel this is not a good idea.

On a barn, you do not need to pull a ground, if you put in a ground stake at the barn. In that case you establish a local ground at the remote panel. It is like a new service coming in. Per code.

paul

N80 · Dec 8, 2007

I am planning a shed which will be 100' away from my cabin. I would like to have three overhead lights and two outlets. I would like to run it off of my cabin and get it done without an inspection. I have access to a trencher. There is room in the cabin's breaker box for whatever type of breaker switch needs to go in there. I'll have a friend who is capable with this sort of thing do that part. (He and I wired the cabin and it passed inspection with no problem, so he knows what he is doing. I do not, Ijust do what he tells me to.)

Can someone give me an idiots guide to how to do this? What type of wire. What type of conduit. Does there need to be any sort of 'box' at the shed? Thanks again, but remember, I'm totally ignorant about electrical.

lhfarm · Dec 8, 2007

N80 said:
I am planning a shed which will be 100' away from my cabin. I would like to have three overhead lights and two outlets. I would like to run it off of my cabin and get it done without an inspection. I have access to a trencher. There is room in the cabin's breaker box for whatever type of breaker switch needs to go in there. I'll have a friend who is capable with this sort of thing do that part. (He and I wired the cabin and it passed inspection with no problem, so he knows what he is doing. I do not, Ijust do what he tells me to.)

Can someone give me an idiots guide to how to do this? What type of wire. What type of conduit. Does there need to be any sort of 'box' at the shed? Thanks again, but remember, I'm totally ignorant about electrical.

I did a search on "barn electric service" and found several good threads. Check out this one http://www.tractorbynet.com/forums/...ice-barn.html?highlight=barn+electric+service