David wrote:

Seems to me the plastic pipe doesn't help at all, except for
mechanical protection. All my utilities are underground and all are
just PVC jackets in the dirt (except for gas, water, and wa


Pretty much mechanical protection only. If there's no drain then the
pipe serves to make sure the wiring sits in a pool of water forever. At
least with direct burial, you only get random wettings. A layer of sand
around the cable would serve to protect from damage.

Other than mechanical protection, the other use of pipe is to allow
future installation of wiring between buildings, etc

The city authority here now requires a two inch PVC pipe for all new
underground residential electrical services. It has to go from the meter
out to the property line. The concentric neutral (or URD cable, if you
prefer) is installed in the pipe.

The reasoning is that if the cable ever has to be changed because of
damage, the large pipe will allow easy re-pulling.

It seems to me that if the wire is damaged to the point of needing
replacement, you have far more serious problems than just the wire. A
collapsed conduit would make change impossible.



mike