Power to barn and a generator from house
#1
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Power to barn and a generator from house
Sorry, this may be a long post but trying to figure out best plan of action:
Bought a house that was wired for 200A service but has a 150A panel with 5 open spots.
Want to build a pole barn (30x40 and 120ft from house) and have power fed to it from main panel with 100A service)
Also would like to have generator by pole barn to feed house in case of outage due to living out in the country.
Would my best course of action be:
1. Install 200A panel in house
100A breaker on panel in house to 100A panel in pole barn
Transfer switch in house running from generator by pole barn
2. Install 100A breaker in house
Run wiring from 100A in house to 100A panel in pole barn
Double pole 30A breaker with interlock that will feed house from pole barn
3. Install 50A breaker in house
Run wiring from 50A in house to 50A panel in pole barn
Double pole 30A breaker with interlock that will feed house from pole barn
4. PUNT!!!!
Thanks for all of your inputs on what is the best and the safest.
Bought a house that was wired for 200A service but has a 150A panel with 5 open spots.
Want to build a pole barn (30x40 and 120ft from house) and have power fed to it from main panel with 100A service)
Also would like to have generator by pole barn to feed house in case of outage due to living out in the country.
Would my best course of action be:
1. Install 200A panel in house
100A breaker on panel in house to 100A panel in pole barn
Transfer switch in house running from generator by pole barn
2. Install 100A breaker in house
Run wiring from 100A in house to 100A panel in pole barn
Double pole 30A breaker with interlock that will feed house from pole barn
3. Install 50A breaker in house
Run wiring from 50A in house to 50A panel in pole barn
Double pole 30A breaker with interlock that will feed house from pole barn
4. PUNT!!!!
Thanks for all of your inputs on what is the best and the safest.
#2
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From just your post, I'd go with option 3. Running wire 120' to service more than 50A will get expensive quick.
However there are a few questions that should be answered before a definite answer is given.
What size is your generator?
What are you wanting to run off your generator?
What are the power requirements/needs for your pole barn? Lights only? Welder? 220v saws?
Will the equipment in the barn be used occasionally or regularly?
Are you burying the wire or running it overhead?
However there are a few questions that should be answered before a definite answer is given.
What size is your generator?
What are you wanting to run off your generator?
What are the power requirements/needs for your pole barn? Lights only? Welder? 220v saws?
Will the equipment in the barn be used occasionally or regularly?
Are you burying the wire or running it overhead?
#3
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All are the valid option, except you have to run separate line for generator feed from pole barn to your main panel in all cases. You cannot use same line because there is no way to interlock your main breaker.
You will also have to install grounding rods if your barn is detached from the house.
You will also have to install grounding rods if your barn is detached from the house.
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8750 running power
Would like the ability to be able to control the panel in the house if there is a need but would settle for well, crock, corn stove, living room, 2 bedrooms and 1 bathroom
Pole barn will have 8 led shop lights inside, 4 exterior led day/night lights, 8-10 outlets. No welder but will have an air compressor
Pole barn equipment used occasionally, except for the exterior lighting
Wire is being buried.
What wire would you recommend for the run underground for the 50A?
Should the double pole 30A be on the house or the pole barn so I do not backfeed the line?
Would like the ability to be able to control the panel in the house if there is a need but would settle for well, crock, corn stove, living room, 2 bedrooms and 1 bathroom
Pole barn will have 8 led shop lights inside, 4 exterior led day/night lights, 8-10 outlets. No welder but will have an air compressor
Pole barn equipment used occasionally, except for the exterior lighting
Wire is being buried.
What wire would you recommend for the run underground for the 50A?
Should the double pole 30A be on the house or the pole barn so I do not backfeed the line?
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OK. So a 50A from house to pole barn to feed the pole barn.
A double pole 30A at the house, with interlock, that runs from the power inlet box at the pole barn to the house.
What size wire for the 50A?
What size wire for the wire from the power inlet box for the generator to the double pole 30A at the house?
All be underground. Can i run them in the same trench or different?
A double pole 30A at the house, with interlock, that runs from the power inlet box at the pole barn to the house.
What size wire for the 50A?
What size wire for the wire from the power inlet box for the generator to the double pole 30A at the house?
All be underground. Can i run them in the same trench or different?
#6
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Are you planning to run conduit between buildings or do you plan to do direct bury? I suggest PVC conduit, it's cheap protection.
If doing conduit my choice of wire would be #4 Al XHHW-2 for the 50A-60A feed and #8 Al XHHW-2 for the 30A-40A generator inlet power back to house. If direct bury same sizes in RHH/RHW-2/USE-2.
If doing conduit my choice of wire would be #4 Al XHHW-2 for the 50A-60A feed and #8 Al XHHW-2 for the 30A-40A generator inlet power back to house. If direct bury same sizes in RHH/RHW-2/USE-2.
#8
I would recommend a 60 amp breaker in the main panel with the #4 aluminum wire (XHHW) which is allowed per NEC 310.15(b)(16). Also 60 amp breakers are widely available.
The panel in the house should able to be left as is.
Use a 100 amp panel in the pole barn with a main breaker as they are very reasonable in price.
The panel in the house should able to be left as is.
Use a 100 amp panel in the pole barn with a main breaker as they are very reasonable in price.
#9
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I verified the max wire size for 50A and 60A looking at Square-D breakers as an example and it is #2 max. If using individual wires such as the XHHW for the entire run it needs to be in conduit from panel to panel. All conductors can run in same conduit, make sure conduit is sized properly.
#10
... except you have to run separate line for generator feed ...
Or you can use the semantic difference that you have one feed (as a branch circuit) from the main house to the barn (subpanel) and you have one feed from the barn (generator pad) to the main house (panel interlock or transfer switch).
#11
Your situation is an exception to a rule that only one feed may run between the main building and an outbuilding
#13
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Regardless if something in the barn is being used or not the branch feeder to the barn is live via the generator powering the main panel in the house. The power inlet for the gen is not considered a supply feeder to the barn, it's a supply feeder to the house. There is only one supply feeder to the barn. The NEC says there is only to be one feeder that provides power to a structure.