wire in plastic conduit

[geneP]

I went to the box store and bought wire and conduit to bury a lighting circuit to the new garden shed. I thought I was buying copper 10/2 w/ground underground wire, but when I got ready to install it I found it is not UG wire. I'm putting it in the water-tite UV resistant schedule 40 pipe. Can I use this wire? I'm assuming it will stay dry in the conduit.

 

[k0ua]

Unless the conduit can be sealed airtight it will fill with water due to the water in the air condensing in the colder underground conduit.

James K0UA

 

[Inspector507]

The wire underground must be rated for that, pipe or not.

 

[Rustyiron]

Underground (direct bury) or exposed (outside) wire is called UF. I think you'll be ok with what you have in conduit. I have heard that in underground conduit it is best to use the loose wire without the jacket (thhn). But that's what circuit breakers are for!

 

[geneP]

Alright, it is marked UF-B. I'm accustomed to the underground wire that is mean to skin. This wire has a vinyl/plastic jacket that encases the neutral and two insulated wires like the tuff stuff, but skins easily. Google says it's ok for direct burial, so I guess I'm OK without another trip to the store?

 

[Inspector507]

UF-B stands for underground feeder with 90 deg insulation. You should be OK.

 

[geneP]

thanks
Gene