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I'm running two circuits outside to other side of yard. I don't have much experience pulling wire so I wanted to make sure I'm doing it right. I have stranded and solid 10awg. I purchased both not sure which to use. I figured my new construction house is all EMT with solid wire, I will use solid to stay consistent.

The solid wire is much stiffer, so I purchased the wire lube to help pull it through and watched some videos about trying pull string in multiple places and electrical taping it.

I will have about a 40ft run of EMT in the basement and then a 60ft run of PVC outside. The PVC will have the LB coming put of house, two 90 deg sweeps (coming out of house, and going up to receptacle), and two 45 deg bends.

I will most likely be doing this myself, so can I pull each wire individually? It will be two circuits, so 5 wires total, (2 hot, 2 neutral, 1 ground).

I purchased a 500ft role, and plan on taping each end to color code. So I was going to pre-cut 5 wires and mark them and pull starting at the junction behind the LB and through PVC, then feed the rest the opposite way through the EMT, basically piecing the EMT as I feed it.

Is this a good idea? Also, can I pull one wire at a time through PVC to make it easier? Or is there best practices to follow to reduce nicks in wires.

Finally, can I pull a 6th wire through and leave it unused to possibly be used in future for a 220 volt with neutral.

This is for a pool circuit and general use receptacle. As of right now I don't need 220 because it's an Intex storable pool. But later on when upgrading the pool pump or heater, may need a 220.

Machavity
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eaglei22
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    You should have purchased several colors of wires. White for Neutral, Green for Safety Ground. – Michael Karas Sep 15 '17 at 05:24
  • @MichaelKaras he can live with just white, because you can remark white to be hots, not the other way round. Ground must be bare, but you only need one of them. He's gonna regret using solid wire, though. – Harper - Reinstate Monica Sep 15 '17 at 06:46
  • What size is the conduit? – Retired Master Electrician Sep 15 '17 at 08:37
  • Conduit size is 3/4 – eaglei22 Sep 15 '17 at 09:25
  • @RetiredMasterElectrician Conduit size is 3/4 – eaglei22 Sep 15 '17 at 09:31
  • @MichaelKaras Actually I did purchase a 100ft reel of green for ground, but white for the others as it was $79 for 500ft vs $29 per each 100ft reel. I thought you can use color tape to mark the wires? – eaglei22 Sep 15 '17 at 09:31
  • @Harper I am up for stranded if that will make life easier. I just saw my whole house was done using solid, so I wasn't sure if there was a particular reason. Contradictory to what I have been reading, solid thhn is actually more expensive by me. Anyhow, I figured using solid would bring less attention to me by the inspector when seeing it, considering the rest of tge house, granted mostly 14awg and 12awg though, is solid. But, I am all for not making the job any harder than neccessary. – eaglei22 Sep 15 '17 at 11:10
  • @MichaelKaras now I am reading this article stating, I can't remark the wires.. http://www.diychatroom.com/#/topics/52460?page=1. Now I am confused. The problem is, I think my run may need more than 100ft, but at the junction, before the LB i can split the connection correct? This way I can buy the proper colored wires using a 50ft and 100ft spool. Also, since it is two circuits, should I use red for one hot and black for another to help identify it better? .. maybe I should ask this in a seperate question. – eaglei22 Sep 15 '17 at 11:42
  • If you used red for one circuit it would always be beneficial for later circuit identification. – Michael Karas Sep 15 '17 at 12:19

1 Answers1

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Wiring methods

EMT and other fixed metal conduit works as a grounding path, so you only need ground wire where the conduit is otherwise. Green, green/yellow or bare is allowed for ground wire. You don't need a ground wire per circuit, only per conduit, but it must be large enough for the largest circuit present. If bare, it must be copper outdoors.

You join a ground wire to EMT by getting a #10-32 screw and fitting it in the pre-threaded hole in the junction box. Do not use a sheet metal screw.

Conduit outdoors in conduit is outdoors. It's pretty much a foregone conclusion that your conduit will fill with water at times no matter how much you try to seal it... that's why you use THWN wire. It's designed to soak.

I have no earthly idea why someone would use solid wire in conduit, perhaps because they were buying (cheaper?) receptacles and switches not listed for stranded wire, or because they were a Romex Kaiser**. It's not worth "fixing", but I wouldn't do any more of it. It's fine for them to mix, just make sure your devices are listed to take stranded wire, and notably backstabs are not, but those are unreliable in any case.

Stranded wire costs about 5% more here. After your first time wrestling 6 solid wires and a GFCI into a 22cu.in. box, you won't mind paying 5% more.

Pulling

You have a tough pull due to the four bends, so gear up for a big one. THWN-2 is already pretty slick and lube won't be worth the unbelievable mess IMO.

The main way to prevent damage is first to thoroughly de-burr, and second prevent kinking, by watching the wires as they enter.

You cannot splice inside the conduit body. Out of the question.*

Pulling one wire at a time isn't better, it's worse. The big hank of wires will mutually help each other as well as provide added strength, whereas pulled individually the existing wires will drag on the new. Don't tape them mid-run, they need to slide a bit to go around corners.

Similar circuits

Beware of NEC 225.30, which generally prohibits running two similar circuits to a building. So having two unswitched 120VAC circuits may be disallowed. However 225.30(D) considers them dissimilar if they are switched, or a different voltage (240V). So the quickest way to clear 225.30 is put one of the circuits on a switch for some reason. Nowhere in the code does it require you to use the switch.

Marking wires

Tape is the key to marking when you don't have 8 colors of wire.

Don't distinguish wires unnecessarily: for instance the two hots going to a 240V heater or 120/240 dryer don't really need to be distinguished from each other.

In your case you need to distinguish two hots from each other, and two neutrals from each other (why? Because you might put a GFCI on one), and potentially a third spare hot.

You can put any tape color on any wire color, but it doesn't always do what you want:

enter image description here

Same-color tape is a little subtle, but is useful for marking. With colored tape it usually doesn't quite match the color or finish of the wire, and you can feel it.

In cable, it's easy to tell which wires are partner to a white, since they emerge from the same cable. This can drive you crazy in conduit with 4 whites coming out of a conduit. In conduit, remarking whites to a hot is disallowed (in most cases) but this cuts both ways: you can use the colored tape to distinguish different wires.

* To be pedantic about it, Code says any box/body is only a conduit body until you splice in it, then, it's a junction box... and must use junction box fill rules. This makes them way too small to splice in, in practical application. Even if the conduit body is wildly oversized for the wire, making the splice strangles the remaining capacity of the conduit, defeating the purpose "room for expansion" to oversize.

Now to be super, duper, duper pedantic, literally NEC says conduit bodies use conduit rules, but they have anything but thru wires, they are still conduit bodies but have to use special fill rules that are identical to the junction-box fill rules. And then, junction boxes use junction box rules, unless they have nothing but thru wires, then they are still junction boxes but use special rules that are identical to the conduit body rules.

** you can tell when conduit work was done by someone used to working in Romex, because they stay as close to Romex practice as possible, e.g. choose only black, white and red for the wires, and occasionally use a white for a switch loop. The old WWI German flag colors. Add green and you have the Pan-Arab colors LOL.

Harper - Reinstate Monica
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    One point -- 225.30 likely does not apply to the OP's scenario since there's no building involved. – ThreePhaseEel Sep 15 '17 at 20:42
  • Thank you Harper for your response. Great information. I do have a couple follow ups. First, for the splicing, i was thinking if I do buy the colored wire, I may have to use a little more than 100ft, so i Would most likely need to buy a 50ft and 100ft. I was thinking of splicing at the junction. If I ran the ground at the junction box behind the LB, can I piece together the wires at this point? And to my next question, buying the colored wire would double my cost, since I don't have any wire or use thhn often i figured having a 500ft spool of white wire and coloring with tape... – eaglei22 Sep 15 '17 at 21:36
  • As you mentioned should be used sparingly, but I noticed this thread, states it wouldn't be allowed for 10awg wire.. http://www.diychatroom.com/#/topics/52460?page=1 so would this not even be an option for me? Also, for the spare hot, I would leave an unmarked disconnected white wire to signify it is a spare wire? – eaglei22 Sep 15 '17 at 21:40
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    @eaglei22 nope, I'm wrong after all. Rolled up my sleeves to find the proper NEC cite to support my claim, and by golly, remarking a white is only allowed in multiconductor cable, and almost never in THHN wiring. Sorry you have to re-buy cable, I have to redo some work too. Sell the rest on Craigslist. Here I am complaining about "thinking in cable" and I was relying on the rule for cable. Looks like they made a Romex monkey out of me! – Harper - Reinstate Monica Sep 15 '17 at 22:54
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    Hey, I guess I helped you learn something new lol – eaglei22 Sep 16 '17 at 02:17
  • So that dead wire needs to be white thwn correct? AND how would i mark it? – eaglei22 Sep 16 '17 at 14:50
  • As we just figured out, your spare wire needs to be colored for a hot or white/gray for a neutral. If you're not sure that's a problem. most likely *one* spare wire would be a hot because that would enable you to convert one 120V circuit to 240. – Harper - Reinstate Monica Sep 16 '17 at 19:51
  • I believe there is an error in this answer: "You cannot splice inside the conduit body." See NEC 314.16(C), especially 314.16(C)(2). https://www.ecmag.com/section/codes-standards/box-fill-calculations-part-xii – RustyShackleford Jun 18 '18 at 19:12
  • No there's not. The blog is lying, contriving nonsense situations to illustrate the rule. What the rule really says it's if there's anything other than straight through wires present, it has to use junction box fill rules. Note, the blogger cannot show an real example where you would ever do this. In both his examples, he wildly oversizes the conduit *and then* uses fantasy conduit bodies that don't exist! Real 3/4 elbows are 7ci. Real 1" tees are 12ci. Practical conduit body sizes are way, way too small. It's not even worth running the numbers. Except in blogs, apparently. – Harper - Reinstate Monica Jun 18 '18 at 20:31
  • Here's a right-here right-now real-world example. I'm running 1-1/4" PVC conduit underground to a shed, with 10awg XHHW. I'll put an LB box on the side of the house, where I'll join the XHHW to NM-B from a breaker. My conductor count is 2*3+1 (3 conductors spliced plus one for EGC); so I need 17.5 cu-in. The LB boxes are marked at 24+ cu-in. Even if I upgrade to 8awg later, I'm still good. – RustyShackleford Jun 18 '18 at 22:37
  • Maybe you think my example is nonsense because I'm not coming close to the maximum wire fill for 1-1/4" conduit, but it seems reasonable to me, given the length and sinuousness of the run, and the inexpensiveness of going to larger conduit. – RustyShackleford Jun 18 '18 at 22:37
  • Yours is a corner case. But at least your example isn't using made up numbers. You have a reason for supersizing the conduit, either easier pulls or future-proofing. That's not normally done. But even then your plan fails at #6. And still, why not just do it in a junction box? – Harper - Reinstate Monica Jun 18 '18 at 22:51
  • Spending a few bucks extra for future-proofing isn't normally done ? My plan is perfectly reasonable. Why add a junction box when I can just do it right there in the LB body that's gotta be there anyhow ? Sorry if I got under your skin, but the sentence in your answer "You cannot splice inside the conduit body. Out of the question" is wrong, pure and simple. – RustyShackleford Jun 19 '18 at 00:57
  • You haven't though. You are painted into a corner because you have no cubes left in the conduit body. You can't even add a pair of #14s (8ci) in for a yard light. If you need more wires through there, you are cooked because you don't have the length to bring the #10 splice indoors to a box. You would have to replace the CB with a bigger CB or preferably a proper junction box. Also something smells fishy, why splice *there*? Are you bringing NM outdoors? Proper strain relief? – Harper - Reinstate Monica Jun 19 '18 at 02:07
  • Let us [continue this discussion in chat](https://chat.stackexchange.com/rooms/79075/discussion-between-harper-and-rustyshackleford). – Harper - Reinstate Monica Jun 19 '18 at 02:18
  • @Harper, if I want to do as you suggest and put a separate junction box inside the crawlspace, how should I run my XHHW wires from the LB body to the junction box ? It's not ok to have XHHW or THHN un-protected, even in a crawlspace, is it ? Do I need to run add'l conduit, presumably with several cascaded reducers (since I'm using a 1-1/2" LB body, and even a large j-box would not have openings nearly that large) ? – RustyShackleford Jun 23 '18 at 22:00
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    Standard practice is straight through the wall with a nipple of 1-1/2 Rigid. It is threaded so it goes right into the conduit body with no adapters, so the body can lay flush and your building hole doesn't have to be weird. Bet your meter is that way. One inside in the dry, any box with a 1-1/2 knockout, those start at 4-11/16 which isn't that big... but if you go 10" square, you are 314.28 compliant for any wire that could possibly fit in that conduit. OTOH you don't need to fit a 314.28 compliant box on day one, as at-the-splice boxes are easily changed. From there NM, since not outside. – Harper - Reinstate Monica Jun 24 '18 at 00:05