Replies

1. 
   McMark | Oct 07, 2009 03:58pm | #1

   It is done all the time in commercial work.  PVC, EMT, ridgid, smurf, IMC.  Just don't run it in the same conduit as line voltage, but you probably already knew that.

    

   Never seen conduit specifically made for running LV in, could possibly not be UL rated? 

2. 
   tek | Oct 07, 2009 04:12pm | #2

   I'd run it in the blue pvc if you can get it. Completely takes the guess work of what's what down the road when you decide to pull more wire.

3. 
   renosteinke | Oct 07, 2009 04:14pm | #3

   Sure, there's a problem ... just not the problem you would expect!

   Low voltage is FAT wire. You will want to run at least 3/4" EMT, maybe even 1", or your pulls will be impossible.

1. 
   jimcco | Oct 07, 2009 04:26pm | #4

   And use sweep el's not sharp corners. I think those "in the future" lines should all be "home run" types. Voice of experience :(

1. 
   McMark | Oct 07, 2009 05:20pm | #5

   I'd run it in the blue pvc if you can get it. Completely takes the guess work of what's what down the road when you decide to pull more wire.

    

   The blue is EMT, not PVC.  Looks like it is all UL rated, just colored differently to make it easier to spot, and to make sure that line and LV isn't ran together

    

    

   And use sweep el's not sharp corners. I think those "in the future" lines should all be "home run" types. Voice of experience

    

   All pre-made 90* ells for pulling are "sweep".  So called sharp corners either are not electrical fittings, or are pull boxes like LB's

1. 
   gfretwell | Oct 07, 2009 07:00pm | #6

   They do make larger radius "sweeps", perhaps that is what he is talking about. I know our PoCo uses 2" with a sweep that is twice what the normal radius sweep you see in the big box store.
   It makes it easier it pull in those 4/0 Al triplexes and quads they use, particularly when the raceway ingests a little sand.

2. 
   renosteinke | Oct 07, 2009 07:01pm | #7

   We're confusing two different products.

   Yes, there is a blue-colored EMT, and it is listed for every use any other EMT is for. EMT is thin-wall steel conduit.

   There is also the blue 'smurf tube,' technically known as ENT, or electrical nonmetallic tubing. It's made of PVC, but is not to be confused with PVC conduit (NMC). Since the OP is from Chicago, I doubt he's allowed to use it.

1. 
   McMark | Oct 07, 2009 07:14pm | #8

   http://www.alliedtube.com/

    

   The blue EMT is marketed specifically for LV, but obviously has all the UL rating to be used anywhere appropriate

4. 
   DanH | Oct 07, 2009 07:41pm | #9

   Buy a can of blue rattle paint and paint the ends so the sparkies don't get confused. Use sweeps or large boxes for turns -- never LBs.

   As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
5. 
   Norman | Oct 07, 2009 08:28pm | #10

   Until Harold Washington had the code relaxed, conduit was required for low voltage applications in Chicago. Of course it was routinely ignored, building inspectors used such sillyness to solicit the 'cash adjustments' required for the inspectors approval.

   I too thought of using some kind of PVC instead of EMT, since all you really want is a repeatable chase. You really do want a larger diameter chase than what 3/4" EMT is going to provide.

   Good luck.

1. 
   brucet9 | Oct 07, 2009 11:10pm | #11

   PVC can be a problem for cat5, cat3 and other twisted pair cables due to welding of cable sheath to the PVC. Higher end teflon sheathing may be fine, but standard plastic may not.I worked for a telecom company doing work at a major NASCAR track where a 25 pair cable in PVC conduit for several years had welded itself to the conduit (plasticizer migration) such that it could not be pulled back out when corrosion problems due to moisture required replacement.BruceT

1. 
   Norman | Oct 07, 2009 11:17pm | #12

   Who woulda thunk? Thanx for the info.

2. 
   DanH | Oct 07, 2009 11:19pm | #13

   I've seen smurf tube used fairly frequently for LV cables. I would guess that it's a bit less likely to develop an unbreakable weld than the solid PVC.
   As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz

1. 
   brucet9 | Oct 07, 2009 11:59pm | #14

   Might be formulated differently too.BruceT

6. 
   [email protected] | Oct 08, 2009 01:37am | #15

   I'd make it over sized, and use large radius sweeps for all bends.  I'd also run extra empty conduit from a central location to select areas if I could afford it. 

   Twenty or thirty years ago, nobody would have predicted that computer system wiring would exist in home environements, or the high end home theater systems with 4 and 5 pairs of speakers. 

7. 
   PedroTheMule | Oct 08, 2009 03:14am | #16

   Hi jgskilsaw,

   I use pex in cases like yours......cheap fast, makes nice gentle bends.....fasteners already available etc. I've only been using it for about 7 years though.....I've been back to add things down the road and haven't had a weld yet.

   I run 2" + pvc between floors for the "Who knows what" stuff......with a crawl space or drop ceiling basement, you can then run stuff to an attic through these chases...from there you can do most anything.

   You'll need to plug them to prevent a fire chase......old coathanger folded around fiberglass insulation....push it into the pipe and bend a handle on the end. Passes with flying colors in NC and it's easy to remove and replace when adding future wiring.

   Run a big pipe behind the TV if your AV amp & tuner will be in another location.....my primary equipment is in the Butlers Pantry with IR Remote relay from the TV and all the cables fed behind the wall. We don't have a formal living room so this allowed things to finish much nicer in the Great Room.

    

    

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