What to use for underground wiring condu
Going to run some underground wiring for some yard lights..want to put the wiring in conduit, for protection and if I ever need to pull wires someday.
Is there a difference if I use Schedule 40 ( white pipe) or Sched 80 ( the Grey stuff)?
Thanks
Replies
Don't they make Sch40 grey PVC? That rings a bell to me. I'm pretty sure you don't use the white. Someone else will surely speak up. BillHartman ... think he might have good electrical knowledge. Can't figure out how to forward or connect this w/ him.
Edited 9/11/2008 5:25 am ET by Clewless1
I believe the grey has uv inhibitors, important for where it comes above grade. And yes they do make sch.40
Rich
Use schedule 40 gray below ground level and use schedule 80 for the above grade portion of the run that is exposed.
This will meet code. White pvc can't be used as conduit.
Having said this, I believe the most important part of your installation involves the bury depth. Code requires 18 in. of cover. If no inspection is required, and/or you decide to bury the conduit in a shallower ditch, you should use the heavier walled [schedule 80] for the complete run.
The color has NOTHING to do with the "schedule" of the pipe!
The white stuff is for plumbing. It is not sunlight resistant, and relies, in part, on the water pressure inside to strengthen it.
The gray stuff is for electrical work, and IS sunlight resistant, as well as having a stiffer formulation.
Speaking of outdoor pipe ...
It's best to run individual wires, to proper "hand holes." If you insist on running a cable - like UF - then the pipe has to be BIG; probably 1-1/4", or you'll never be able to pull it out.
"Hand holes" - they kind of remind you of 5-gallon buckets, open at the bottom - are what you use for your junctions. So-called "outdoor" boxes do not have enough room, will NOT keep dirt and crud out, and usually corrode away in no time at all.
Edited 9/11/2008 9:41 am ET by renosteinke
thanks guys...
I'll have to ask the Elect supply folks about them Hand Holes.