We buy USE-2 cable.

What the dual rating actually means

The jacket usually carries both designations, RHW-2 and USE-2, along with the size, the voltage rating and a sunlight-resistant marking. RHW-2 is the wet and dry location rating at 90 degrees Celsius. USE-2 is the underground service entrance rating for direct burial. One cable, two listings, and the print on the jacket is what a buyer reads first.

That matters for re-use. A reel marked only USE is an older single-rated cable, still perfectly good in the ground but not usable in a wet location above it. A reel marked RHW-2/USE-2 is the modern dual-rated product and is treated differently. Photograph the print along the jacket rather than the reel tag alone.

Solar work and the DC surplus it leaves

A commercial array is designed on a string calculation, and the DC home runs are ordered to reach the combiner with slack. When the layout changes, the inverters move, or an array is expanded, the cable is pulled and replaced with a different length. The original reel, often 8 AWG or 6 AWG copper, comes back partly used.

Residential solar leaves smaller lots but more of them. A roof array on a house in Katy or Pearland uses short runs, and the installer's van collects partial coils that never get used again. Those coils are still dual rated and still useful, and they are bought as a group rather than one at a time.

Array work also leaves cable that was never installed: reels bought for a phase two expansion that was cancelled, still banded, still carrying the supplier's tag. That material is the easiest to review because nothing about it has to be inferred. It turns up more often than the growth of the solar market would suggest, usually in the back of a warehouse.

• DC home runs in 10, 8 and 6 AWG copper
• Partial reels from a layout or inverter change
• Cut lengths with connectors still fitted
• Grounding conductor in 6 AWG bare or green
• Aluminium USE-2 from larger array and service work

Connectors do not add value and are usually cut off before re-use, but they do confirm the cable was installed in a DC circuit rather than left on a shelf.

Rural services, wells and long runs

Outside the Grand Parkway, plenty of property is on a well and a private service, and both are fed with direct burial cable. A pump replacement pulls the drop out of the casing, and a service upgrade replaces the run from the pole or the meter pedestal. Those runs are long, often a hundred feet or more, and the cable comes out in one piece when it comes out at all.

Agricultural and light industrial work adds more: irrigation controls, gate operators, barn and outbuilding services, outdoor lighting runs. Much of it is aluminium in the larger sizes, which changes the grading. Aluminium USE-2 is bought, but it is judged more strictly on the ends, because aluminium does not tolerate water sitting in an open conductor.

Long runs are where the history shows. Cable buried for twenty years comes out with a jacket that has taken on the colour of the soil, and the insulation underneath is usually sound if that jacket is intact. What kills it is a nick from a shovel or a pull rope, because water finds a nick and works along the conductor from there.

• Well pump drops in copper, 10 to 6 AWG
• Service runs from a pole or meter pedestal
• Outbuilding, barn and equipment feeders
• Irrigation and gate operator circuits
• Aluminium direct burial in larger sizes

Cable pulled from a well casing arrives wet. That is expected, and it is graded on the conductor and insulation rather than on the water alone.

Sending a USE-2 lot

Send the jacket print, the conductor size and material, the approximate footage, and whether the cable is dual rated. If the reel is a partial, say roughly how much has been used. A single photograph of the print and one of the cut end will confirm the rating and the metal in most cases.

For cable that came out of the ground, note how it was removed and whether the ends were sealed afterwards. Direct burial cable that was pulled with a machine often has jacket damage along its length, and a photograph of the middle of the run is more useful than another photograph of the end.