Can ring terminals be safely crimped to THHN?

I am building an off-grid system with two 120V 10kW Quattros in parallel. I need to connect the AC out on each Quattro to the electrical panel. The AC out of the Quattro uses an M6 bolt. I would like to make the connections to the Quattros by crimping M6 ring terminals onto #2 THHN wire. The non-crimped end of the wire would then be run through conduit into the electrical panel and secured to the panel lugs with a set screw. However, my concern is that each strand in THHN is much thicker than the strands in the welding wire that is more commonly used in off-grid systems.

I would like to hear the community's thoughts on this use of THHN. Will the larger strands in THHN provide a sufficiently low resistance connection when crimped onto a ring terminal (assuming the crimping is done correctly)? Does anybody have any experience with using THHN in this capacity?

Thanks

It depends on the crimper you use.
THHN does successfully crimp down, it requires significantly more torque though.

I've crimped ring lugs onto THHN without issue from 10 AWG to 2/0

THHN stranded, yes.
THHN solid, no.

I crimp THHN stranded wires almost daily.
From 18 gauge to 500 kcmil.
Most of the wiring in my system will be THHN.

I've used as die-less crimper to crimp thhn before, I cannot remember the gauge but it was not as large as 2 awg thhn. I think it was only 8 guage. This is solely going to depend on which type of crimper you use, I'm a firm believer in die-less crimps they provide a more mechanical crimp. The set that I have will cold weld finer stranded wire together. After you make your crimp do an extreme pull test, crimping 2 gauge thhn is going to be a challenge if you dont have a good crimper.

leadacidtrip said:

I've used as die-less crimper to crimp thhn before, I cannot remember the gauge but it was not as large as 2 awg thhn. I think it was only 8 guage. This is solely going to depend on which type of crimper you use, I'm a firm believer in die-less crimps they provide a more mechanical crimp. The set that I have will cold weld finer stranded wire together. After you make your crimp do an extreme pull test, crimping 2 gauge thhn is going to be a challenge if you dont have a good crimper.

Click to expand...

I haven't bought it yet, but this is what I was planning on using:


I'm open to purchasing a different crimper

awbower said:

I haven't bought it yet, but this is what I was planning on using:

https://www.amazon.com/gp/product/B00HJXG3KM/ref=ox_sc_act_title_2?smid=A2TLTYG8U2QKGY&psc=1

I'm open to purchasing a different crimper

Click to expand...

Temco is good quality stuff.

awbower said:

I haven't bought it yet, but this is what I was planning on using:

https://www.amazon.com/gp/product/B00HJXG3KM/ref=ox_sc_act_title_2?smid=A2TLTYG8U2QKGY&psc=1

I'm open to purchasing a different crimper

Click to expand...

Temco makes some of the best crimpers you can buy, I would trust the quality of the dies and the hydraulics also mainly the crimps this will make. I own the die-less crimper from Temco and it’s been crimping for many years now. Only downside to hydraulic crimpers is they can leak over time.

I have never owned a hydraulic crimper.
I have always said that I would like to have one.
But then, I always pull out my long handle die less.
Old habits are hard to break.

Gosh I sure hope so. Myself and the other 10,000 members of my IBEW local have been crimping lugs on #14 thru 600MCM THHN for 40 years. Before that came out it was TW.

awbower said:

I haven't bought it yet, but this is what I was planning on using:

https://www.amazon.com/gp/product/B00HJXG3KM/ref=ox_sc_act_title_2?smid=A2TLTYG8U2QKGY&psc=1

I'm open to purchasing a different crimper

Click to expand...

That looks like a pretty nice crimper…