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Joined: Mar 2004
Posts: 947
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I like to pull nmwu into a raceway:
1) because I can run the raceway and pull the wire into it after the hot-tub is installed, to avoid damage to the cable,
2) to provide an extra of protection, especially where the cable comes out of the ground, but also where it crosses other underground systems, or where rodents are a problem,
3) to allow the wire to be withdrawn and re-pulled without trenching,
4) where I would normally install conductors but because of the location a junction box or flex are impracticable at the ends of the raceway, or
5) where others might install a water pipe, because I have easy access to pvc but not water pipe.
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Joined: Jun 2006
Posts: 613
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0) according to table 19 and 12-100 not a permitted use
1)can do that with rw90 and a piece of LT flex.
2)Can do that by putting a piece of PVC over the cable so there is 8 or 12 inches buried and some above ground. I like to see that for any cable going into the ground where it could be damaged at grade.
2B) I wish I could remember where I read this but there are specific wiring tricks that are very effective at protecting from rodents. I read a long article last year that described specific tips for running loomex in rodent infested areas that mitigates their Gnawing behaviour. If you are going to install a raceway to protect against rodents then why put loomex in the pipe after? short sections of pipe are already accepted as providing mechanical protection and should be permitted.
3) Pipe and wire again as well as cheaper and probably easier.
4) I need an example of this.
5) Finally someone brings this up. Here is the biggest reason the inspector has an untenable position. It is very common practise to allow the use of poly pipe like for street lighting where a tractor and a direct bury digger drive down the boulevard and bury a 1" pipe. Later the electrical contractor comes and installs a cable or single conductors approved for direct burial into the pipe after. I can't recall where this is permitted but it does beg the question why is it OK in poly pipe that is not even an electrical product but not OK in PVC?
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Joined: Mar 2004
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Comment (0) is interesting. I've been treating table 8 like it provided for pulling all cables into a raceway. I'm not alone in that. In industrial locations it's fairly common to add an empty raceway to an open trench for future installations.
Example of (4): Several teck cables were installed under a roadway and spare conduits were added for future installations because re-trenching, even with a hydrovac, disturbs the existing cables, a lot. It's unreasonable to put junction boxes on the ends of conduits that are 20 feet apart, and to terminate a 30 pair shielded cable on both ends. I pulled the 30 pair teck through the pipe.
Could it be that if the cable leaves the conduit and enters an enclosure with a properly rated connector, the conduit, at any length, is just protection? I'm aware that pulling the cable into a conduit that ends in a junction box isn't allowed because there isn't a connector on the cable to take any strain and it's impossible to strap the cable inside the conduit.
Another reason I think it must be allowed, is the emt to nmd adapter. What other use can these adapters have?
I'll guess about the poly pipe. Since it doesn't exist in the code book, the cable inside the poly pipe is technically just underground and needs to be rated for underground use. It's like an underground bore that creates a conduit made out of mud. It simply isn't a conduit.
Anyway, before you reject my work, you'll need a shovel to prove that the conduit extends beyond being just protection.
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Joined: Jul 2008
Posts: 98 Likes: 1
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22-200 does not say NMWU can be installed in a raceway it says it may be installed in a category 1 (wet) location.
Table 19 does not list Loomex of any designation for installation in a raceway so in a raceway it may not be installed.
The heat thing is at best a reach for an answer to prevent the installation of loomex.
Can anyone explain why they want to install it in a raceway? I cannot understand installing a pipe then sticking a cable in it. Expense without benefit? Did you notice the quotation marks in my post? They're there because I was quoting directly out of the bulletins issued by the ESA in Ontario. I didn't write the bulletins, the ESA in Ontario did, so it is allowed in Ontario, if no where else. Plus table 19 does show NMWU for direct earth buriel with protection. I always thought that conduit was protection. As for why you'd do it... in addition to some of the other responses, sometimes it's actually cheaper. Bruce
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Joined: Jun 2006
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Comment (0) is interesting. I've been treating table 8 like it provided for pulling all cables into a raceway. I'm not alone in that. In industrial locations it's fairly common to add an empty raceway to an open trench for future installations.
Some cable may be installed in raceways but from table 19 not that many. LVT, Communications and FAS are listed in table 19 for raceways.
Example of (4): Several teck cables were installed under a roadway and spare conduits were added for future installations because re-trenching, even with a hydrovac, disturbs the existing cables, a lot. It's unreasonable to put junction boxes on the ends of conduits that are 20 feet apart, and to terminate a 30 pair shielded cable on both ends. I pulled the 30 pair teck through the pipe.
I presume the raceways were not terminated into equipment but simply permanently place sleave?
Could it be that if the cable leaves the conduit and enters an enclosure with a properly rated connector, the conduit, at any length, is just protection? I'm aware that pulling the cable into a conduit that ends in a junction box isn't allowed because there isn't a connector on the cable to take any strain and it's impossible to strap the cable inside the conduit.
For example an acwu or teck cable service pipe is installed from below grade up to the meter. You could install the cable through the pipe and put a teck connector after the pipe to terminate on the meter.
Another reason I think it must be allowed, is the EMT to nmd adaptor. What other use can these adaptors have? Below 5 feet an nmsc need mechanical protection where the wire runs on the surface. So by way of example the NM goes down a column to a receptacle. EMT can be installed on the surface where not subject to mechanical damage. I know you are spinning in your chair right now. So loomex needs mechanical protection below 5 feet and EMT is OK for below 5 feet but neither is adequate where either needs mechanical protection. It gets better as rigid pipe can need mechanical protection too. So there is obviously a level of hazard and protection required. Exposed loomex below 5 feet is considered to offer no mechanical resistance to bumping and occasional brush by contact so the EMT is used and a connector is required where the two wiring methods join. Some inspectors will ask you to strip the jacket off inside the pipe.
I'll guess about the poly pipe. Since it doesn't exist in the code book, the cable inside the poly pipe is technically just underground and needs to be rated for underground use. It's like an underground bore that creates a conduit made out of mud. It simply isn't a conduit.
Yes and the cable or wires in it still need to terminate in a connector and must emerge from the poly in a location where the requirements for protection are met.
Anyway, before you reject my work, you'll need a shovel to prove that the conduit extends beyond being just protection. OK I have spent a lot of time on this subject and Honestly I don't often reject this use of NMSC as long as it is the right type for the environment. IE NMWU for wet. BTW with regard for protection under ground. Table 53 lists the depth required for NMWU as 600 mm for non vehicular areas and 900 for vehicular areas. Raceways are 450 and 600 under 750 volts. Installing NMWU into a raceway here reduces the depth required to raceway depth but to get another 150mm grace a raceway is not mechanical protection for the purpose of this table. This goes back to the original question when it provides mechanical protection then a raceway is acceptable when that is what the pipe is installed for. In this case the raceway can be cut off at grade and assuming the MNWU does not need protection there then it can run on its merry way without the pipe terminating in a box or enclosure. Many of the scenarios offered here are interpreted and enforced differently by different inspectors. If you believe you have a scenario where running a cable not listed in Table 19 in a raceway you may need to defend it to your local authority. Most of the scenarios here would likely be accepted. My point is in making it a discussion.
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Joined: Mar 2004
Posts: 947
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I'm not sure that I'll ever have to defend this one to the local authority. They have a problem with enforcement. If they enforce, or relax, a rule in one situation, they must apply the rule equally to every electrician in every similar situation. Now that it's established that nmwu can be pulled into a water line, the worst they can do is make me pull out a pvc and put in a water line instead. I'd love to see that rejection notice!
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Posts: 57
Joined: August 2003
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