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Discussion Starter · #1 ·
I realize this/these questions have been asked a million times before on this forum, but I appreciate any help that will help me drill down on exactly what materials I need and what I need to do. Because I live on a rock pile and it would take forever and a day to dig a trench, my goal is to run wire/cable in sch40 conduit that is mounted up under the eaves of my shop about a 100' from a junction box mounted next to my 200A service panel. The thought behind the junction box is to give extra room for bringing the wire/cable into the 2x4 wall before entering the service panel. The conduit will go around my shop to a 125A sub panel located in an attached carport that will support a welder,car lift, large compressor, and lights/outlets. For economic reasons, I would like to use aluminum wire/cable. My questions are: What size and type of wire/cable do I need? What size pvc conduit can I run the specified wire/cable in? Also, is it acceptable to use LB conduit bodies to get around the corners of the shop or would those bodies be too tight for the specified wire/cable? I plan on using the long sweep elbows for other change of directions as needed. Thank you for all your help.
 

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As you obviously will not have 200 amps at the new panel (being fed from a 125 amp panel), I would use #1, for the 2 hots, #2 or 3 for the neutral, and #6 for the ground. I would use 1 1/2" PVC. If available I would use schedule 80 because PVC run horizontal will tend to sag bad especially if exposed to the sun. Some inspectors will not accept schedule 40 above ground. An LB is fine for outside corners and 90 degree elbows for other locations.
Use a 100 amp breaker in the carport panel.
 

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Discussion Starter · #3 ·
Thank you for responding. The new panel will be 125 amp sub panel fed from a 200 amp main service panel. Will the aluminum wires and conduit you referred to remain the same for the scenario I just indicated? Also, are those aluminum wires you listed thhn, thwn, SER, or ?
 

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Sorry for misreading. For full 125 amp you will need 1/0 for the hots and #2 for the neutral. You say the carport/shop is attached to the house? If a separate Bldg, a ground rod will need to be provided.
 

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Not attempt to run a cable like SER inside of conduit.
 

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Discussion Starter · #7 ·
I. Forgot to say to use single conductors. Not sure insulation type for aluminum. If it were copper it would be THHN.
I. Forgot to say to use single conductors. Not sure insulation type for aluminum. If it were copper it would be THHN.
What size ground wire and conduit size do you suggest? The carport is attached to the shop that has the 200A main service panel feed. So no ground rod required, correct? From what I've read, I need to ensure the ground and neutral are isolated from one another in the sub panel, correct?
 

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Same PVC size or 2" if need be in order to find schedule 80.
#4 for ground wire.
The aluminum wire is indeed type THHN/THWN.
 
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