I plan on running my entrance service, cable and phone lines underground in separate plastic conduits (about 200′). I am required to use sch40 underground and sch80 aboveground at least for the SE, my question is about the difference between the white drain pipe and gray electrical conduit. Can white be used for the underground with gray above the ground or must it be all gray even underground? Is there a major difference between the two or is it just the color? The phone and cable people don’t seem to care what I use for them, what do you think, white, gray or black? I haven’t look at the price of the different types yet, just thought I’d look my possible options first.
Thanks
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The important thing is that if someone digs up the conduit, they can tell from the color that it's electric vs drain. Lots of folks wouldn't hesitate to cut out a section of 2" drain in an excavation, figuring to splice a new piece in later. You could actually open your self to serious liability issues by using white instead of grey.
Your absolutly right, never gave a thought to the digging issue, gray it is!!
there is also a caution tape to lay in above the conduit, good idea
.....the only option you have is to use conduit and fittings that are rated and listed for that purpose .
........what Dan said !
First there is actually very little difference in cost between PVC plumbing pipe and PVC electrical conduit. In use they are about the same cost. Partly because the conduit goes in a little faster because it has a bell end which saves a coupling and the time it takes to glue it in place.
The actual physical characteristics of the plastic are also different. The grey conduit has UV inhibitors that reduce damage caused by sunlight. Some plumbing pipes, also grey, share this characteristic. Grey doesn't automatically mean electrical conduit as I have seen grey plumbing pipe. I have never seen white conduit so white seems to still imply plumbing.
Beyond color and UV resistance the conduit is also more malleable and resilient. Often when demolishing PVC pipes, especially if it has aged a dozen years or so and been exposed to chlorine, I just hit the fittings with a hammer. Most will crack in a few sharp blows. PVC conduit seems much more resistant to this abuse.
Even given new white plumbing fitting I have been known to demonstrate the difference to helpers by having them beat both with a hammer on a piece of concrete. Almost without exception the white plumbing fitting cracks and shatters, beware the shrapnel and wear safety glasses, while the grey conduit is slowly flattens but remains otherwise relatively intact.
Be sure to use long sweep electrical 90's and 45's. I've gone to jobs where the customer proudly announced that he had all the pvc in the ground only to find that the fishtape wouldn't push through the raceway. Sewage will go through a tight 90, but wires won't.
And don't forget your expansion couplings.
If you haven't drawn blood today, you haven't done anything.
And don't forget your expansion couplings.
Want to know how and where it is used. Thanks.
the fittings allow expansion of about 10 '", but very little deflection.....
you simply glue them into the conduit run and you are done, but
I have never used them. .......even in this ditch"
Wow, some serious conduits.
Must be from the transmission lines at the background.
In front of our building they're installing a rack of 16 conduits that look to be about 6" each. Stacked 4x4 and encased in concrete.
Pretty substantial duct bank. Looks like a compacted gravel base, makes for a nice work surface, most likely to be poured into concrete once completed. That and the plastic erosion shield makes me think this is a really major industrial site like a power plant. Maybe nuclear. Likely a highly regulated site. Possibly government. Likely union from the neatness. Another guess would be a defence site. Perhaps a missile, radar or control node but the depth of the duct bank looks a bit shallow. Only looks like 4' of cover. Usually they like 10' or more. Of course they might move in a mountain of fill after everything is installed.
....my thanks for the nice comments, actually , this was a Peaker in Aurora ,Il. the duct bank was ALL of the wiring for six small LM type units ALL 3" ...the bottom two rows were GRC for Control and Instrumentation, the unfinished rows were eventually run out , and encased,... yes ..it was Union ,
the top of the concrete manhole was finished grade.
there were four LARGE units that are pipd out out the same manhole. the last week we we there, one of my crews pulled in the 1,ooo,oooth ft of cablethat's me in the blue on the left leaning over"
Edited 10/1/2005 6:15 pm by maddog3
will go through a tight 90, but wires won't
Sure they will, just not necessarily at the radius of the plastic elbow (Hey, Derryl, aint this s'posedta run 78'?) Cable will cut pvc or nmt at too tight a radius (sometimes cuts it at a 'good' radius, too--"Hey Wylbur, ease up on the puller, the panel moved the last time")Occupational hazard of my occupation not being around (sorry Bubba)
well, that was redundant...
The warning tape is required by code I believe.
If you haven't drawn blood today, you haven't done anything.