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I'm using 12/2 direct burial cable to get power to my shed. When using the conduit to bring it up from the ground to the breaker box, where does one start to strip the cable? Would it be from where it enters the conduit (that would be buried), or just before it exits the conduit ( inside the breaker box)?

My understanding is you are not allowed to run direct burial through conduit.

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    Unless you've already got the trench dug and the cable in the ground, I'd suggest you reconsider entirely. If you put conduit in the ground between the shed and the power source, it means your trench can be shallower (easier to dig). Then you can pull individual wires through the conduit and make your life much easier, especially if you have more than one elbow to navigate. There are a ton of questions here about pulling cable through conduit, so you should be able to find plenty of examples.
    – FreeMan
    Commented Apr 14, 2021 at 14:39
  • Trench is ready to go,, its only approx 40 ft long only bend is where it needs to go up to the surface
    – Jben04
    Commented Apr 14, 2021 at 17:19
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    Should anything ever happen to the cable, or you ever decide to upgrade from a single circuit to a small panel in the shed, conduit will allow you to pull new wire through, while direct buried cable requires you to dig it up & replace it. Conduit is highly recommended, but, of course, the decision is yours.
    – FreeMan
    Commented Apr 14, 2021 at 17:42
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    The sheath must be intact for at least 1/4" past the point it enters the service panel. More is better. Commented Apr 14, 2021 at 18:44

2 Answers 2

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For the reason why you can't strip the cable where it enters the conduit, that has to do with rating of the individual wires. While it is possible that the individual wires inside a UF (or NM or any other) cable may be the same type/quality (THWN) that can be run directly in conduit, there is no guarantee. Even if they are "basically the same thing", if the wires are not individually marked to indicate they are manufactured to THWN specifications, you can fail inspection. On the other hand, if you run a cable through conduit where the only purpose of the conduit is to provide protection from damage (e.g., UF cable outside, NM cable inside) then the rating of the wires inside the cable doesn't matter.

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There is nothing wrong with running UF thru conduit, it's just tough and you have to pay attention to "fill requirements"...go big! Then land it in the sub-panel and strip it there. There are other requirements for a sub-panel, but that question has been asked and answered so many times here that if you do a quick search, you'll find what you need to know.

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  • I picked up 1/2" conduit for the 12/2 cable. so you recommend i rather use 3/4 or even 1 in?
    – Jben04
    Commented Apr 14, 2021 at 17:24
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    There are others better qualified than me to answer that question regarding fill capacity. But like Freeman said in a comment above, it's only 40', get 4 sticks of conduit, use individual wires (THHN/THWN) in a conduit. If you really wanted to "do it right", run 2 hots, a neutral and a ground, That would give you 120/240v on the sub-panel. Because it's a detatched structure, you'll need to add ground rods, and bc it's a subpanel, isolate the neutral from the ground. Commented Apr 14, 2021 at 17:35
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    The conduit inside diameter must be at least 138% of the widest width of the UF cable. UF is devilishly wide, so this can be frustrating. Commented Apr 14, 2021 at 18:44
  • Encore says the greater diameter of 12/2 uf-b is 0.415", and the Belden fill calculator says that a single cable will fit at 53% fill allowance. Increasing cable count decreases fill percentage, so more cables would need individual calculation. tools.belden.com/conduit-capacity-calculator Commented Apr 14, 2021 at 19:38
  • @Harper-ReinstateMonica Yep! agree completely. + on that. I never get why ppl want to direct bury cable when conduit is so relatively inexpensive and individual wires are much less expensive than UF cable. With conduit, they might even break even or save some $$$ and end up with a much better product. Commented Apr 14, 2021 at 19:46

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