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51

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 ...


37

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 ...


15

Your biggest concern here is going to be the condition of the interior. If they are at all corroded or otherwise rough on the inside they run the risk of damaging the insulation, which can lead to an eventual short and/or electrification of the pipes. Protecting the wire where it enters and exits the pipe is also a concern. Basically I think you could do ...


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 ...


10

How about an EMT slip on bushing? This about explains it all. Catalog Page EDIT: I think there are three goals here - clamp the NM cable in place, protect the cable from the sharp edge of the EMT, and secure the EMT to the jbox on one end. I showed you how to protect the romex coming out of the EMT. To secure the NM cable in place, where you want to ...


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 ...


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

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) ...


9

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 ...


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 ...


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

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

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

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 ...


7

For the duct work, since we don't know how many cables you are talking about, I suggest ENT (Electrical Non-Metallic Tubing). It is flexible, corrugated and comes in a range of sizes, same as PVC. You can even use PVC connectors on ENT if in a bind. For termination, you can either use a box / terminating structured media center or make your own with a J-...


7

Exposed ground wires are normal. In the last year I've seen a main panel and 2 subpanels approved with exposed ground wires. They were 6ga stranded.


7

I guess a big question is: do you need to conform to code? If you have a building permit out, the inspector may want to see your wiring before you cover it. Your pipe may violate code, and the inspector won't approve the work. Are you going to sell this house someday, with the wires running into the pipes visible? If so, the buyer's building inspector will ...


7

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 ...


7

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.


7

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 ...


7

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 ...


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 ...


7

The upside of data cables is there's no limit to how many you can run in one conduit -- no 310.15(b)(3) thermal current limits (PoE may change that), and no 225.30(D) limits on multiple circuits. Really, your problem is all about the ease of pulling multiple cables this long distance, especially given the delicacy of Ethernet. Larger diameter conduit and ...


6

What you're calling outdoor Romex is actually called type UF (underground feeder) cable, it resembles Romex, but it's not. UF cable is THHN conductors plus a ground encased completely in PVC. Romex is a brand name for non-metallic paper bonded cable (NM-B, as printed on the jacket) with a PVC jacket. This is why type UF is suitable for burying and wet ...


6

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 ...


6

Your two choices if you want normal AC power out there are: Direct burial cable. Figure something like $0.50/foot for 12 gauge cable, though it's possible that you will need to buy a roll of 500' instead of just 300' since 250' or 500' are standard lengths. If you do this, you will need to make sure that it is buried 24", and I highly recommend putting a ...


6

Could you put a couple intermediate "manholes" in the path? So instead of one 200m pull you have 3 or 4 shorter runs? You'd still run a 200m cable, but this way you only have to pull it 50-65m at a time. I'd definitely run at least one, maybe 2 empty conduits - it's a lot easier to run an extra conduit now than to re-trench it later


6

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:


6

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 ...


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