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Discussion Starter #1
I recently saw a post by Jim Port that describes what I want to do but would like some further clarification. I will soon be selling my present house and want to put some lights and receptacles in a detached carport with a small shop area in rear. I already have underground conduit but never wired anything. The total wire run will be about 60 feet.
1. Jim mentioned in the other thread about running UF 12/3 with ground to have two 20amp 120V circuits which is all I need. Could I run this thru the already in place 1 1/4 inch conduit to a cutoff switch like used for AC unit then branch out to two circuits using 12/2?
2. If I did this then I wouldn't need any ground rods at the carport?
3. Since I already have the conduit would it be just as good to run four wires of
12 thnn?

Thanks
JM
 

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I recently saw a post by Jim Port that describes what I want to do but would like some further clarification. I will soon be selling my present house and want to put some lights and receptacles in a detached carport with a small shop area in rear. I already have underground conduit but never wired anything. The total wire run will be about 60 feet.
1. Jim mentioned in the other thread about running UF 12/3 with ground to have two 20amp 120V circuits which is all I need. Could I run this thru the already in place 1 1/4 inch conduit to a cutoff switch like used for AC unit then branch out to two circuits using 12/2?
2. If I did this then I wouldn't need any ground rods at the carport?
3. Since I already have the conduit would it be just as good to run four wires of
12 thnn?

Thanks
JM
You can only have one circuit run to any exterior structure. This is why the 12-3 was mentioned. With this setup, you'd have a MWBC which will actually give you two circuits and be code compliant. Once you run four 12 ga THWN wires, that becomes two circuits and would not be code compliant. The other option is to do a sub panel.
 

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A "Handy Husband"
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You can only have one circuit run to any exterior structure. This is why the 12-3 was mentioned. With this setup, you'd have a MWBC which will actually give you two circuits and be code compliant. Once you run four 12 ga THWN wires, that becomes two circuits and would not be code compliant. The other option is to do a sub panel.
A Multiwire Branch Circuit certainly can be run with 4 THWN wires, 2 hots, a neutral and a ground. Ground rod not required. Your pullout disconnect is fine.
 
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Discussion Starter #4
A Multiwire Branch Circuit certainly can be run with 4 THWN wires, 2 hots, a neutral and a ground. Ground rod not required. Your pullout disconnect is fine.
I have a switch type disconnect (sq D with a 60 amp rated two pole switch).
I just looked at it and unsure how I would wire it for the two 120v circuits. It has the two lugs for the two hots and a two hole ground bar. If I run a 12 white , green, red, and black do I use the ground bar for green only. Then the incoming neutral white would be spliced to the two whites for the branch circuits and not be grounded to box?

Thanks
JM
 

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A "Handy Husband"
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Use the ground bar for the grounds, splice the neutrals with a wire nut. Keep the neutrals separate from the grounds..
 
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Does it matter if I use a double or two single breakers at the main Panel?
You can use two singles if you use a handle tie.
 
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