DIY Solar Power with Will Prowsevideo

Off-grid Solar Buyer's Guide: DC Wire and Connectors

December 2, 2019 · 23 min · 718K views

Hands compare blue DC connectors' copper walls

What this video covers

Pure copper wire and thick-walled, UL-listed copper lugs are essential for safe, long-term off-grid solar installations.7:04 Avoid copper-clad aluminum (CCA) wire, which is common on sites like Amazon; it carries less current than pure copper, expands and contracts at different rates when paired with copper lugs, and corrodes rapidly, creating fire hazards and inverter connection failures.0:51 High-quality installations require a gas-tight mechanical crimp that creates a cold weld, which should be protected with heat shrink rather than anti-corrosion compounds like Nolox.10:19

For primary inverter and charge controller connections, use pure copper welding cable for its flexibility and ease of termination.8:06 Marine-grade tinned copper wire is necessary for environments exposed to moisture, salt, or oil.11:01 For solar arrays, use only UV-rated, UL-listed PV wire, such as products from Temco, to prevent insulation degradation from sunlight.16:07 Automotive or marine-grade primary hookup wire is suitable for smaller DC appliances, while oxygen-free copper speaker wire may be used for low-voltage, indoor LED lighting.13:13 Proper wire sizing remains critical for all applications.

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