Hi all,
We are building a house with a very long driveway (520ft). When we lay the phone cable, I’d really like to put in conduit to make future upgrades easier. However, as my husband pointed out, pulling cable through 520 ft of conduit would be painful, if not impossible. Is there anything appropriate for this sort of application?
Thanks, I’ve been learning a lot from you all the past few months.
Jo
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Replies
The bigger the conduit the easier. Go large. two or three inch, four wouldn't hurt. Leave a pull string. With the distance involved you might want a pull rope. It's not all that bad.
Riverfest 2005. Be there, or be square.
http://www.hay98.com/
It is done all the time commercially. Certainly a larger conduit would help. Electricians have winches specifically made for wire pulling, and use a generous helping of duck butter, too.
If you wish, you could lay the power and telephone as direct burial, because they are unlikely to ever change. Then run your cable TV in conduit so it could be upgraded, or run a spare conduit for future whatever, like optical fiber perhaps.
The power wiring has to be in conduit under the driveway, but can be direct burial elsewhere if deep enough and placed in sand free of rocks.
Generally the larger the conduit the easier the pull. But there is a point of diminishing returns. Given that it is unlikely that you need more than three lines, redundancy making it six pairs, and that this cable is little more than a quarter inch in diameter anything more than a 1" PVC conduit is overkill.
On a commercial site and a relatively straight run 520' isn't long. Not for communications cable of this size. You could pull in a pull line with a vacuum cleaner. Compressed air on one end, this takes a special fitting that isn't hard to make, and a vacuum on the other and you could likely pull the cable in in a single shot without benefit of a line. A bit of a risk but that's why I make the long green.
Of course nothing says the 520 feet has to be a single run. A small ground box type hand hole is cheap and one or two of these would reduce the pull to a couple of piece-of-cake 260 or 173 foot runs. Nearly a single man job even for the inexperienced. And at 173' a 1" conduit would easily take both the phone and cable TV.
Around here, Verizon's been burying conduit all over the place for their Fiber To The Premises (FTTP) upgrade (not this neighborhood, unfortunately). The distance between pedestals is this distance, or longer.
If I was in your shoes (I have an ~800' driveway), I'd do what you're planning to do.
It doesn't work real well to put the pull string in place while you're placing the conduit; the PVC cement gets on the string and cements it to the inside. Suck a string through with a Shop Vac. Conduit pistons or "mice" work the best; although I've found that a plastic grocery bag with a little air in it works OK, too.
Pulling CAT5e cable through 1" conduit with a rope should be pretty easy; and if they every decide to deploy FTTP in your neighborhood ('don't think they'll ever do mine), the telco crew will love you.
geode ,
if you use PVC electrical conduit for this long run, use ridgid steel elbows for any 90 degree bends in the run !
A pulling rope or string will burn a groove into all PVC elbows of ANY radius making it very difficult or impossible to pull the cable through. As mentioned above pull boxes would be smart
try to use at least 1/4 " rope and avoid string, picture an egg slicer or cheese slicer, and that is what happens inside PVC when pulling small strings through. The best rope would be a flat woven one, 1/2" wide min. Also remember, gravity is our friend
maddog
"The day I can't help out a friend......
That's the day I got something better to do! "
Edited 6/29/2005 7:05 am ET by maddog
Edited 6/29/2005 8:10 am ET by maddog
Edited 6/29/2005 8:10 am ET by maddog
4lorn1, Barry, mdAny of you use conduit that comes is spools?I am not sure what it is. I am under the impression that it is a polyethalene and similar to the PE water pipe.I have seen a couple of places where I see it sticking out of the ground by the pole and the house for runnin phone or cable. Usually yellow or orange, 3/4 - 1".And I see a ton of it being plowed into the ground by the interstate. From the distance it looks like 3 - 4". I think the first put in a couple of years ago was for fiber optic. But I am seeing a lot of new put in on this one section that they are rebuilding and I am wonder if it might also be power for the lights.I am guessing that it is what is called HDPE by the 2005 code.http://tinyurl.com/c8vr6"Article 352. Rigid Nonmetallic Conduit (Type RNC)RNC conduit is a listed nonmetallic raceway of circular cross section with integral or associated couplings, approved for the installation of electrical conductors. This type of conduit gives you much of the advantages of rigid conduit, while allowing installation in areas that are wet or corrosive.Article 353 High Density Polyethylene Conduit: Type HDPE ConduitThis is a new article in the 2005 NEC. Check with your AHJ before attempting to use HDPE as your AHJ may not yet recognize or approve of it. This type of conduit has been in use in the U.K. for a long time. It is lightweight and durable. It's resistant to decomposition, oxidation, and hostile elements that cause damage to other materials. It's mechanically and chemically resistant to a host of environmental conditions. Uses include communication, data, cable television, and general purpose raceways."Anybody know how it joined? I know that for PE water pipe the only 2 options are barb fittings & clamps or thermowelding.
it is sometimes referred to as "smurf tube " , the fittings are just the snap on type and most of the time the ends are left bare by the utilities. The largest I have run was 2" in cable tray in the mills. care needs to be taken when cutting this stuff as the rope inside tends to creep back into the coil something as short as 500" could be laid as one piece, but would have to be protected under driveways (of course) maddogThe day I can't help out a friend.......
That's the day I got something better to doEdited 6/29/2005 8:52 am ET by maddog
Edited 6/29/2005 8:56 am ET by maddog
"Smurf tube" is ENT, Non-metallic tubing for interior use. In a few towns around here, Verizon is installing miles of the HDPE stuff for FTTP project. All of the Verizon yards in this county have dozens and dozens of the big rolls of this stuff waiting to be installed. They usually use directional boring, and they don't splice it from what I've seen. So far they've left the ends sticking out, where I assume pedestals will be installed.
The conduit they're using is colored orange; I notice the gas guys use yellow flexible tubing. 'interesting ,they now seem to be using the same color coding that the cable locators use when marking roads (red - electric, blue - potable water, etc.). I wonder when Types UF and USE will come in red?
Back OT, yea, use the string to get a pull rope in place, and pull the wire with that. Cable lubricant works wonders. I assumed this was a mostly-straight run, with maybe just 90 degree sweeps at each end. They make fiberglass sweeps, athough you won't find them at the Big Box.
it must be a regional thing , over here, smurf, is anything nonmetallic and uniduct is what goes in the ground,The day I can't help out a friend.......
That's the day I got something better to do
there is another type ... "uniduct " the shape is more like a pancake and it is thicker than the smurf . It is used for road lighting here as the voltage is usually 4160 . That stuff is laid in with specialized equipment though maddog!The day I can't help out a friend.......
That's the day I got something better to do
In my last "real" job, we used HDPE by the mile to place fiber optic cables. You can get it in spools that hold several hundred feet - or in 20' "sticks" that are glued up like PVC or ABS.
For a trench and bury installation, I would recommend the sticks in either 1.5" or 2" diameter with sweeps (not elbows) where needed. Sticks are easier to handle since the HDPE takes a "set" from the spool and can be a real PITA to get it to lay in a trench. (We only used spooled HDPE on directional bore jobs where we pulled it back thru the bore.)
500+ feet should be an easy pull as long as there are no sharp bends. If your installation has bends, put in a pull box. I would also put in one more duct than you think you need - it's better to put in in and not need it than to have to re-trench someday.
How stiff are the sticks?I don't realy know, but from the look of the stub left sticking out of hte ground it looks like that ran it and curled the end up at the pole. Much like you would do with a hose. This was for 3/4" or so for cable.
Bill is the stuff you're looking at corrugated / ribbed ? if it is that stufff is not HDPE , more like smurf or ENTThe day I can't help out a friend.......
That's the day I got something better to doEdited 6/29/2005 10:35 am ET by maddog
Edited 6/29/2005 10:36 am ET by maddog
No it is smooth.Like this stuff.http://www.bdiky.com/hdpe-products/hdpe-products.htmFrom a distance it looks much like the PE pipe that you can get in rolls at most any place with plumbing supplies. Often used for wells and irrigation applications. ENT is not approved for direct burial.I found this interesting link.http://www.usda.gov/rus/telecom/materials/pdf_files/2-hc-02-24-05.pdfIt appears to be approved materials for rual telephone applications.Anyway it list "plastic" and "flexiblle plastic" conduits.Under flexible it has HDPE conduit.Under plastic is list PVC sch 40, and 80 which are standard conduits.But it also list types B, C, D, EB and DB. I have no idea what those are.
The ribbed stuff is what I have installed in tray , outside with a cover I have seen it run underground in some subdivisions, (which violates the code)
it also was used to build a hotel for a casino here !
they ran it all over the decks itstead of EMT the HDPE must be what I called "uniduct" most likely the DB EB is easy bend... the wall is very thin which allows for large radius field bends ,it is used for comm. and data but has to encased in concrete hereThe day I can't help out a friend.......
That's the day I got something better to do
The sticks are about like schedule 40 PVC. You connect them with glued couplings and can curve them - up to a point.
When you see stubs sticking up, they may ends of sweeps - or someone may have just bent the HDPE into a tight curve. On hot summer days, we sometime laid HDPE on the street for a couple of hours and it bent pretty easily. On a rainy January day, fuggedabouddit!!! - lol
It's fairly normal to see the plowed-in conduit ends sticking up like that. Usually they come along later and do them up properly, but I doubt whether they splice on sweeps, since that would set them up for leaks.
Communications cable conduit structures don't worry about leaks. I've pumped out manholes near San Francisco Bay that refilled within a few hours. In one case, we had to run the pump continuously just to stay ahead of the flooding - lol
Except that it's a PITA if you go to pull a cable in and the conduit is filled with muck.
Not really. You can slug a duct if necessary - just adds a little time to the job - lol
I see the stuff on spools mainly being plowed in. It's used a lot for telephone/fiber around here. And I believe some of the orange stuff is actually gas pipe -- plowed in like the rest.