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54

Yes, NM cable can be in conduit. In fact. NEC calls for it to be in conduit, when protection from physical damage is required. National Electrical Code 2011 ARTICLE 334 Nonmetallic-Sheathed Cable: Types NM, NMC, and NMS II. Installation 334.15 Exposed Work. In exposed work, except as provided in 300.11(A), cable shall be installed as ...


39

Empty conduit is your best bet here. No point in guessing what (if anything) you may get, and guessing wrong. While you can leave a pull string in it, you can also just vacuum a pull string into it when the time comes (that's what is normally done to install it in the first place). If you do leave a string, don't worry about how big/strong it is: it can be ...


13

The best future proofing you can do is over-provisioning the amount and size of conduit. Pulling a cable through a relatively straight 200m run is not out of the question especially with proper cable lubricant and a large enough conduit. I would suggest not pulling anything like fiber without proper specs on the gear on both ends. There's a good chance ...


11

Yes, this is a good idea, but a few details. No more than four cables per conduit, unless you're willing to upsize ALL the cables to the next larger size. That is 310.15(B)(3)(a). The conduit needs to be fairly large, because the cables are oval. Each oval cable is treated like a single wire of the wide dimension (because they twist). They can't fill the ...


10

There is a widespread belief that the NEC does not allow NM-cable in conduit, but does allow THHN (the individual wires). This belief is incorrect. However, it is for some reason lesser-known that NM-cable cannot be used in outdoor conduit at all, stripped or otherwise. So, the answer to your question is: stripping is a common but misguided (unnecessary) ...


10

You can run type NM cable in conduit, as long as the conduit is sized appropriately, and is not in a wet or damp location. If you remove the sheath from the conductors inside NM cable, you cannot use the conductors for anything (anything electrical anyway). Type NM cable is rated, listed, and labeled as a cable assembly. The conductors inside are not ...


10

Using the same hand-bending tools you already have, you can approximate a larger bend radius by leaving short sections of straight conduit in between multiple bends. Below is a picture showing the minimum radius bend you currently achieve with your hand tool (picture on top) and then using three segments of bending coupled with two straight lengths to ...


10

Derailed by Derating Your plan is a non-starter, even if you overcome the fill issues you're having, because of the other limit the NEC places on conduit fill; namely, the derating factors found in 310.15(B)(3)(a) that limit ampacity based on the number of current-carrying conductors. The first two rows of the table are normally not an issue because nobody ...


10

You can transition wiring methods at a junction box. Use the EMT wiring method up to the junction box (whole nine yards with fittings and clamps). Then use the NM wiring method beyond it. The junction box must remain accessible without screws, nails or demolition (other than the ones on the junction box lid, of course). If you don't like the aesthetics ...


9

Now you've learned the hard way, the same way the rest of us learned, why they say "measure twice." A spade bit may work for this trick, but an auger bit may be easier to control. First, use the bit to cut a hole in center of some scrap wood. A piece of plywood that's 4"x6" would work well, and a 2x4 that's 6-8" long would also work. You need a few inches ...


9

Speaking as someone who does a LOT of data cables... Pray to your deity of choice regarding (lack of) lightning nearby. The extent to which I prefer fiber optic for outside data runs is influenced by years of dealing with copper outside data runs, and the failures resulting - but few, if any, cameras are set up for power + fiber optic, so you'll want a nice ...


8

You can, but it really isn't worth it... It's a nightmare to pull NM (Romex) is already solid wire except in the large sizes, and now you have 3-4 wires bound together. You are trying to pull this around maybe 14" radius elbows, and if the NM gets twists in it (it always does), it really drags in those places. It's just a stiff, miserable pull - enough ...


8

In addition to Tester101's excellent answer on when NM-B can be run through conduit, there is a section in the NEC which indirectly prohibits running NM-B through conduit in specific scenarios: From the 2014 NEC: 312.5 Cabinets, Cutout Boxes, and Meter Socket Enclosures. Conductors entering enclosures within the scope of this article shall be ...


8

Depends. If the conductors are 6 AWG or smaller. There is enough free space. It's not a short radius conduit body. The volume is durably and legibly marked by the manufacturer. Only then can the conduit body contain splices. In your specific case, I don't see the volume listed in the specifications section on the Home Depot page. So you'd have to check the ...


8

There are collar boxes available that have conduit KO's (knockouts). Just install one on top of the existing device box and run your conduit. This one is even better as it has more volume: Brand: Steel City, Part number:531511234UB Here is a raised device cover to be used with the 4x4 box shown. They can be had in any number of different configurations.


8

No, you cannot. Unless you're not covered by National Electrical Code (or similar), you don't care about following codes, or you're also installing a permanent barrier or listed divider. National Electrical Code Chapter 8 Communications Systems. Article 820 Community Antenna Television and Radio Distribution Systems. 820.133 Installation of ...


8

Go out the bottom, otherwise the hole or any flaw in the conduit will bring water, rust and failure into your box. Use two conduit bodies to make your 180 degree turn. You can do this pretty tight to the box surface if you really want to. Do not strap the conduit to the box, strap it to the wall. Use THWN-2 wire in the cable. This is rated for outdoor ...


8

You mean 800.133. And this very concept of mixing comms and power is highly improbable. I know you're casting around for a way to do this, but this sort of "hopeful reading" is very highly prone to confirmation bias. NM-B is always useless in conduit Using NM-B in the conduit wiring method is not illegal, but buys you nothing but headaches. It's very ...


8

With rigid or intermediate metal conduit ($$) you can follow code without going very deep - 6" under dirt, 4" under a concrete cover of at least 4" thickness extending at least 6" to either side. Unless you want a concrete path through your garden along the route of the conduit, that's not likely what you want. Rigid and intermediate metal are tough enough ...


8

NM in conduit under a deck (or a slab) is NFG You cannot legally run NM cable in a wet location, and the inside of a conduit in a wet location (such as under your deck, or buried beneath a slab) is still a wet location. Don't believe me? Well, we start with NEC 300.5(B) for what's going on sub-slab: (B) Wet Locations. The interior of enclosures or ...


8

Too many circuits per pipe All this is about the derating rules in 310.15(B)(3)(a), see ThreePhaseEel's answer. When I first saw your other question, I thought "Oh boy, I smell a too-many-circuits problem coming". I thought I should warn you to run multiple conduit, but I didn't mention it because it was out of scope. Now, if you were strictly working ...


8

Yes, when doing in-bench or in-cabinet work like that, I am very comfortable with EMT, provided it is anchored properly and not used as a hanger for other things.


8

I don't know if the exact match you're looking for exists, but you can get decora inserts (for the type of plate in your picture) that fit one, two, or three keystones. It'll be plastic rather than metal, but the plastic will match the keystones while the metal matches the box.


8

Yes, you can run NM/Romex cable through conduit. This is generally used to protect the cable in exposed areas. As long as the conduit is designed for electrical work, it should be fine. Sorry, you can't use Spa hose (but I've seen it tried) They sell special bell ends for PVC conduit that ensure that the cable does not get cut or damaged by the end of ...


8

Not sure where you got the idea that you need THWN-2, only. All you need is the W. TWN, THWN, RHW, XHW, XHHW, etc. are all perfectly fine, because they have the W that means they are waterproof, that means they can go in outdoor conduit. Most THHN is also THWN and MTW (multiply rated.) If you are in a situation where the wire temperature may be extreme you ...


8

THWN is rated for wet locations As Ecnerwal discusses. The issue is thermal The difference is at the top of Table 310.15(B)(16). THWN is allowed 75 degree C running temperature. THWN-2 is allowed 90 degrees C. THHN also is allowed 90 C Southwire is making a disclaimer: they are saying they don’t guarantee #14-10 will be THWN-2. What’s on their mind is a ...


7

I'm guessing it's plumbing, not conduit. Unless you actually see wires running through the tubing, I'm not convinced it's conduit. In the US only certain types of conduit are listed for use, and I'm sure they are similar in Canada. Copper is not among those listed, so it's not likely it would be approved by an inspector. In a comment you mentioned that the ...


7

NO! Regular couplings, those in the first image, are NOT pull points. Pull points are conduit bodies or boxes, or even those silly little elbows in the second image. My suggestion would be to install a conduit body at strategic locations. For your installation you really only need one. Conduit bodies:


7

One trench the whole way will be easier to pull cable through. You could make it direct, one straight line, or closer to it than otherwise. Fences can get blown over, run into, replaced for service, or removed for aesthetic reasons, which will become more of a pain to deal with if you run conduit along the fence. Also its less pleasurable to look at ...


7

Accessory dwelling units are complicated While outbuilding feeders and standby generators are both common things to have -- your combination of having an accessory dwelling unit in the outbuilding with standby generator support for that accessory dwelling unit, alongside having shared, or "house", loads, such as the well pump, that will also need standby ...


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