Service-Entrance Cable. A single conductor or multiconductor assembly provided with or without an overall covering, primarily used for services, and of the following types:
Type SE. Service-entrance cable having a flame-retardant, moisture-resistant covering.
Type USE. Service-entrance cable, identified for underground use, having a moisture-resistant covering, but not required to have a flame-retardant covering.
Notice that the difference between the two cable types is that type USE is not required to have a flame retardant outer jacket. That is what limits it to outdoors, if sunlight resistant, and underground. Type SE has all the characteristics of Type USE and it also has a flame-retardant covering. Type SE can be used anywhere that type USE can be used as well as being used as feeder and branch circuits in any application were type NM can be used. The U in Type USE is to limit it's use to underground rather than to limit the use of type SE to above ground. We have batted around the idea that conduit is a wet location when installed outdoors. I don't think that any of us would argue that a conduit that is above ground outdoors is uniquely different than the same conduit underground.
Let me point out that Type SE Style R is the only type of SE commercially available in most ares that has four conductors. Has anyone here seen four conductor type USE cable. How do you think that three phase service gets done were the cable has to extend indoors to reach the service equipment cabinet? Do all of you build raceway to enclose individual single conductor type USE cables?
[This message has been edited by tdhorne (edited 11-26-2004).]