Q) How can I tell if a cable is listed for use in wet locations?
I am trying to specify a PLTC/ITC twisted, shielded pair cable (and a 3C/shielded) - 18AWG or 20AWG, which is listed for use in wet locations. (It will be run in conduit underground and in conduit exposed to the weather in a chemical plant).
The manufacturer keeps directing me to their catalog where it says things like "suitable for direct burial" (for some cables) and "moisture resistant" (for others). I would think that a UL listing would be something the manufacturer would be able to point to rather easily and definitively. if they make such a product and aren't just trying to snowball me.
The article contains a link to the UL cable marking guide, where further details are available.
UL does not simply say a wire is "Rated for wet locations." That would be far too direct and simple. Rather, there are a variety of types of cables that are -in addition to their other qualifications- considered suitable for use in wet locations.
For example, direct burial is considered a 'wet' location, so any 'direct burial' rated cable is suitable for use in a wet location. A buried cable is not, however, expected to see much sunlight, so it's very possible that a 'direct burial' cable would not work for an exposed outside location.
Or, another example is your typical extension cord material. It's certainly rated for wet locations - but will not survuve long if buried in the ground.
Thank you very much. That's exactly what I was looking for.
But doesn't it strike anybody as odd that Article 300.5(B) of the NEC requires certain cable to be "listed for use in wet locations". but there doesn't really seem to be such a listing? Odd that.
