Wiring question. Splicing DC wires.

[Amy@altE]

unitaps are too expensive, compare to wire nuts.

Unitaps are more expensive than wirenuts for a reason. Unitaps are cheaper than a fire.
Not sure if you are getting the system inspected, but most AHJ don't like wirenuts there, they like Unitaps.

[abelov1984]

unitaps are too expensive, compare to wire nuts.
easiest and best way probably to use MC4 in a JBs as well, but would need bigger boxes..

didn't say about splicing outside.

Jumping to THHN to make 120' home run (all enclosed).
Yes - cheaper installation. smaller JBs, smaller conduit, smaller penetration LB's and etc.
thx

[Amy@altE]

Or even better, instead of a junction box, use a Pass thru box like Wiley Electronics Acme Conduit Entry (ACE) Pass-Through Enclosure or on an asphalt roof, a SolaDeck 0786-3R5 for pass-thru and roof penetration into conduit.

[SunEagle]

Splicing DC conductors of PV circuit (PV wire #10) in JBs (on the roof) with THHN (#10) for going to the home run in the conduit. And using wire nuts for splicing..Big deal?
Thx

Wire nuts are never a good solution to splice wire in an outside junction box. They will eventually come apart and cause issues.

Better to use a wire termination equipment such as the Burndy Unitap that Amy suggested.

[russ]

Why would you ever need a splice?

He is trying to go cheap with short lengths of wire?

[Sunking]

Why would you ever need a splice?

[Amy@altE]

A better solution is to use a Burndy Unitap like a BITO4 in a junction box.

[abelov1984]

Splicing DC conductors of PV circuit (PV wire #10) in JBs (on the roof) with THHN (#10) for going to the home run in the conduit. And using wire nuts for splicing..Big deal?
Thx