Definition
PV Wire and USE-2 are both common conductor types for solar PV source circuits. PV Wire is single-conductor, sunlight-resistant, suitable for exposed outdoor installation. USE-2 is direct-burial-rated but not approved for prolonged sun exposure above ground.
Comparison
| Type | Sunlight | Burial | UL Listing |
|---|---|---|---|
| PV Wire | Yes | Yes (in conduit) | UL 4703 |
| USE-2 | No (limited) | Yes | UL 854 |
| THHN/THWN-2 | No | No (conduit only) | UL 83 |
Key Takeaways
- PV Wire: outdoor exposed; sunlight-resistant.
- USE-2: direct-burial; limited sun exposure.
- Both 90°C rated insulation.
- Choose based on installation environment.
- NEC 690.31 governs permitted uses.
Frequently Asked Questions
1 commonly searched questions about PV Wire vs USE-2.
PV Wire vs USE-2?
PV Wire: sunlight-resistant single-conductor, exposed outdoor. USE-2: direct-burial-rated, underground. Both 90°C rated. NEC 690.31 lists permitted uses.
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