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I’m finishing up wiring a sub panel in an outbuilding. There is an underground run of PVC conduit with THWN, which comes up to an LB on the exterior wall. On the inside I used flexible conduit so I could have a tight bend that comes up to the breaker box. Is this code? I can’t find anything in the NEC about this specific instance. I’ve attached a photo for reference.

I’m in the US (Florida). enter image description here

Edit:

The outbuilding is an office/man cave for me. I’m going to finish it with drywall. Currently there are 5 total circuits planned, each 120V: lights, a split A/C (20A max), and some 120V outlets. I don’t plan on ever having any heavy equipment out here, so there aren’t any 220s.

The feeder size is 6/6/6/8 (60A max). I’ll have a 60A double-pole breaker in my main panel and a corresponding double-pole 60A in this panel which will act as a main breaker/disconnnect. I know 60A is massive overkill. It’s a 120foot run and I wanted things to be as efficient as possible in terms of voltage drops.

That still leaves me with 1 open slot that I can’t really think of what to do with. I chose a smaller panel because I didn’t want to stare at a huge panel all day, and I just couldn’t think of any additional needs. Even the outlets could have really been consolidated into 2 circuits instead of 3, but I wanted the isolation for the computers/servers.

I hope I didn’t miscalculate. Am I able to use 2 of the slots in this panel for a double-pole “main breaker”, or do I need a box with a special slot for that?

Edit 2:

Here’s a photo of the bend and panel label. It’s fairly tight, but I don’t think it’s deforming the tube like it mentions in 350.24. I can measure the radius if that helps.

enter image description here

enter image description here

  • Can you provide a close-up photo of the actual bend, and what size is the flex conduit itself? – ThreePhaseEel Sep 11 at 11:41
  • Also, what make and model is that panel of yours? – ThreePhaseEel Sep 11 at 11:42
  • If you need a main disconnect, Harper and Three Phase are the experts on this, this box won't work. – JACK Sep 11 at 12:56
  • The make and model of the panel is an Eaton BR816L125FP. I’ll attach a photo of the bend and panel label. – Jon Wingfield Sep 11 at 12:59
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    What size is the flex conduit, and what's the actual bend radius involved there? – ThreePhaseEel Sep 11 at 23:18
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Liquid Flex May be Okay

NEC 2017 356.1 Liquidtight Flexible Nonmetallic Conduit 

-- Basically says you're good but I cannot tell the size of the flex.
   It looks to be 1in. diameter, which is fine if that is the case.

-- You may need to secure every 3ft or less to be in accordance w/ 
   356.30 for securing runs longer than 6ft if that were to happen.

However, you have other issues to attend to...

Disconnect Means Missing

NEC 2017 Part II 225 Buildings or Other Structures Supplied by a
Feeder(s) or Branch Circuit(s) require a Means to disconnect all 
ungrounded conductors per 225.31

-- Basically anytime you have a separate structure fed by a branch
   circuit or feeder, you need a disconnect means AT THE STRUCTURE 
   to disconnect all ungrounded conductors (and no more than 6). 
   This is often done by installing a main-breaker type panel as 
   opposed to a main-lug which you have used as shown in your 
   pictures.

   The NEC does not define structure and as such a piece of wood 
   driven into the ground with a sub-panel on it could qualify as
   structure to the authorities having jurisdiction.

Back-feeding breaker as a "Disconnecting Means"

Per NEC 2017 408.36 (D) Back-fed breakers used as a Disconnecting Means
MUST be bolted or secured in place as to not be pulled out.

-- Basically this means you cannot just stick in a 60A breaker
   in you current panel and use it as a disconnecting means because 
   it is not bolted in place.  You could use a hold-down kit as 
   mentioned in your comment, but I think you'd do better with a 
   bigger main-breaker panel.

You still need a Disconnecting Means in the outhouse in addition to the rule of 6

Concerning your comment "...Apply 225.33 (A)"    

-- To be clear: Every structure requires at least (1) disconnecting 
   means but no more than 6 to disconnect all ungrounded conductors.

   225.31 has (4) exceptions to the location of the disconnecting
   means, but none are related to the rule of 6.        

Bushings

NEC 2017 352.46 Bushings for PVC based Connectors &
NEC 2017 300.4(G) Insulated Fittings

-- If the feeder conductors are 6 AWG or larger you will need a 
   bushing for the PVC connector entering the bottom of the panel 
   box. 

enter image description here

  • I appreciate the extra considerations. I’ll definitely use the bushing. I edited my question to include additional information that (hopefully) covers your point about the main breaker. – Jon Wingfield Sep 11 at 12:49
  • @JonWingfield I've updated my answer. Your inspector is wrong. Also using a normal residential snap in breaker as a disconnecting means is illegal too – Kris Sep 13 at 18:57
  • I'm not sure I understand? A snap in breaker would require a hold-down. But if there is no "main" breaker, doesn't 225.33 allow the use of up to 6 disconnects? – Jon Wingfield Sep 16 at 13:33
  • @JonWingfield 225.31 requires all structures to have a means to disconnect all ungrounded conductors at the structure. There are exceptions listed under 225.31 but none of those are related to the rule of 6. The rule of 6 is totally unrelated. It requires no more than 6 disconnect means per structure. – Kris Sep 18 at 1:17
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Given the large size of the feeder you are bringing in here, that subpanel is very, very, very small. This is exactly what we warn people about: a situation where you run out of usable breaker spaces and now have to go to some serious expense or inconvenience.

If you're thinking "well, well, I can just use double-stuff breakers and cram 16 breakers in this 8-space panel" -- not anymore. Double-stuff breakers have gone the way of the dodo bird, as so many circuits do or will soon need AFCI, GFCI or both. Those breakers are not available in double-stuff.

The disconnect switch requirement will already force you to take this back to the store and get one with a main breaker. Now, put in just a few dollars more and get a 16-space or 24-space. Some of them even include "bonus breakers" as part of the combo.

  • Thanks so much for the extra advice. I asked another question on here before I started the work and I received similar advice. I’ve updated my question above with an explanation. I’m definitely open to reconsider since the walls are open, but hopefully I’ve made the right decision. – Jon Wingfield Sep 11 at 12:50
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    @JonWingfield That's what everyone does. They go "I have all the spaces I expect to need right now” and so they button up the walls. Then something else comes along that they didn't expect, and they're like "Oh, snap, I could have avoided this with $20 extra back in 2019”... Of course you're not expecting it... No one does. – Harper Sep 11 at 15:42

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