I have a very long narrow property. Currently I have a 400amp service with a 200 amp panel in the garage and a 200 amp panel in the house. I have 750' 2.5" sch40 run from the garage panel to the new barn. The plan was to put 125 amp breaker in because I think that is the largest breaker available. Then run 2/0 copper or larger need be. I know I'm going to have amperage drop but is it going to be a problem? Can my neutral and ground be smaller wire? Trying to make it most cost effective.
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750' Run to new barn... Help!
- Thread starter Jfresh
- Start date
If you can put together your load values, then one of us can do the voltage drop calculation. Sizing the wire for your application is a much better route then guessing at it. Most one man shops need sufficient power for lighting, welder, air compressor and sometime AC running at the same time. So the best thing would be to take those hard numbers and use them with a small fudge factor to do the calc. Being you only installed a 2.5" conduit it's going to limit your options.
I have a very long narrow property. Currently I have a 400amp service with a 200 amp panel in the garage and a 200 amp panel in the house. I have 750' 2.5" sch40 run from the garage panel to the new barn. The plan was to put 125 amp breaker in because I think that is the largest breaker available. Then run 2/0 copper or larger need be. I know I'm going to have amperage drop but is it going to be a problem? Can my neutral and ground be smaller wire? Trying to make it most cost effective.
Well, lets say a 50 amp load at 750' would require 300MCM alum to limit VD to 3%. Have you talked to your power company, see what they could/would provide (free) and run lines straight to your barn, with a service on it?
theoldwizard1
Well-known member
I know I'm going to have amperage drop but is it going to be a problem? Can my neutral and ground be smaller wire? Trying to make it most cost effective.
First, you need to do a realistic load assessment for the equipment that will be used in that barn. If approximately 50% or more of the loads are true 240V loads, you can uses a smaller neutral. You can almost always use a smaller ground.
At that length, I would check with the POCO about installing a second drop at the barn. At least know what that option costs.
Compare that cost to installing a transformer at each end. Kick the voltage up to 480V at the beginning and the use an autotransformer at the barn to step back down.
wyliesdiesels
Well-known member
I have a very long narrow property. Currently I have a 400amp service with a 200 amp panel in the garage and a 200 amp panel in the house. I have 750' 2.5" sch40 run from the garage panel to the new barn. The plan was to put 125 amp breaker in because I think that is the largest breaker available. Then run 2/0 copper or larger need be. I know I'm going to have amperage drop but is it going to be a problem? Can my neutral and ground be smaller wire? Trying to make it most cost effective.
distance causes VOLTAGE DROP NOT amperage drop. UNLESS u upsize the wire.
As others have said, we need to know your loads before we can figure out what size wire u need.
Also, will this be a one man shop or?
What about water heater, AC, etc...
distance causes VOLTAGE DROP NOT amperage drop. UNLESS u upsize the wire.
As others have said, we need to know your loads before we can figure out what size wire u need.
Also, will this be a one man shop or?
What about water heater, AC, etc...
Yes, yes, yes, but what about the PULL? The conduit is already in place. Can anyone pull that length?
wyliesdiesels
Well-known member
If i were the OP i would see if the PocO can set a pad mount transformer right outside the shop that way thr OP doesnt have to pull all that distance.
If i were the OP i would see if the PocO can set a pad mount transformer right outside the shop that way thr OP doesnt have to pull all that distance.
I did this exact same set up for my brother in law at his tree farm, the requirements here were that the power co. provided the 3" pvc pipe to run from the road tap box and turn the pvc up at xfmer location, they required a pull box every 400'. The pvc pipe run (That I installed) had to be 36" deep and left uncovered in a few spots so they could inspect, after inspection of the service, they came out and pulled a 7200 volt line in, set the pad mounted xfmer and tied my service in. This was the most cost effective route. As several have stated here, I would call your power co. and see what they have to say before I had any more time and $$ invested in this.
MushCreek
Well-known member
Our house is about 400 ft from the nearest power pole, and the POCO won't try to push 240V that far. They had to put a transformer up closer to the house. 750' is a long way for 240V.