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Discussion Starter #1
My 17kw generac generator is currently picking up 4 circuits from my main panel, and 8 circuits (all 15 or 20a) from my sub panel. When this was originally installed, there were 8 - 12gauge thhn wires run in 3/4 seal tite from my generator panel to my sub panel. The seal tite ran through the exterior wall where my main panel is located, underground, and then back in the house where my sub panel is, about 30' away. Now that my basement is gutted. I want to run this inside the house. Can I run all 8 - 12gauge thhn wires in a 3/4 flexible metal conduit? I looked up conduit fill, and that seems fine. What concerns me is the derating. Should I run 2 -3/4" conduits and run 4 in each or am I ok with all 8 in one? All 8 wires will be carrying a load. Thank you!!




Thank you!
 

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JOATMON
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Why flexible? I'd do PVC or EMT....and bump it up in size. The cost difference is almost nothing....

I'd go at least 1"....then later on if you want to add something, you have the space.

And....it's a lot easier to fish a fish tape through pvc or EMT than it is flexible...
 

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Discussion Starter #3
PVC is not code where I am. Emt would not work for me. I have to go behind some studs and there are some twists and turns.
 

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Lic Electrical Inspector
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9 current carrying conductors is the limit for 70% derating. #12 THHN cu will work fine. Only one conduit is needed.
 

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Discussion Starter #5
Thank you! After thinking about it, I'm going to run another piece of greenfield anyway. I have it, the walls are open, and who knows if ill need it in the future. =). Much appreciate the replies.
 
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