I had a chat with SS today, and they mentioned they only carry single conductor red and black wires for connecting solar panels to the inverter. This left me a bit puzzled. Why not use a cable that has both conductors included so I can pull just one cable instead of two? What cables do you usually opt for when connecting panels to the inverter?
3 Answers
People usually go with single wires, like the red and black you mentioned. But, you might come across some dual wire options, though they're not that common. I think it relates to UV protection, too!
There's a reason behind the single wire approach. Different circuits are used in typical systems. Array wiring can be outside if it's the right type, like USE-2 or PVWIRE. PVWIRE is the latest option designed for solar use. Though, you can also go for multilayer cable, but that's rare since the positive and negative wires often go to separate points in the array.
If you're using conduit, the standard is to pull individual THHN or THWN wires through. That's the way the NEC regulations work.
For a more direct approach, you can go through the roof and use Romex from there to your inverter, especially if the inverter is located inside your house.
Thank you! So using conduit with two THWN wires is the way to go? What about the ground wire? Should I include it in the same conduit or run it separately?