PV wire junction question

[GRickard]

Well, this got side tracked.

I am not redoing my roof penetrations to add a soladeck.

Just to clarify, I wasn't saying you should use the soladeck. The Weiduller terminals are just the same type that you would find in the soladeck and can be used in the j-box you already have.

[Paul Land]

well, this got side tracked.

I am not redoing my roof penetrations to add a soladeck.

My connections are not on or even within 2 feet of the roof surface. The junction box is in the attached garage.

I hate split nuts, mostly for the tape. But, i hate spending an extra $60 for the burndy unitaps. So i will likely just do split bolts. If the burndy unitaps was the right connector the decision would be easier.

unless, the mc4 connectors (just like on each panel) are ok inside a junction box. I already have them and they are xleaner than split bolts and tape.

I understand that insulation requirements for ac vs dc are about the same. But it seems that terminations and connections are more important with dc

also, i have two strings. They will see a max of 10a and 7a, so not a huge current load.


Also, on a side note. I got my permission to operate in 3 days! Submitted monday evening, received the pto email wednesday night.

congrats!!!!!!!!!!!

[Mike90250]

I use a zip tie over the top of tape, to keep it from uncurling .

[emartin00]

Well, this got side tracked.

I am not redoing my roof penetrations to add a soladeck.

My connections are not on or even within 2 feet of the roof surface. The junction box is in the attached garage.

I hate split nuts, mostly for the tape. But, I hate spending an extra $60 for the Burndy Unitaps. So I will likely just do split bolts. If the Burndy unitaps was the right connector the decision would be easier.

Unless, the MC4 connectors (just like on each panel) are ok inside a junction box. I already have them and they are xleaner than split bolts and tape.

I understand that insulation requirements for AC vs DC are about the same. But it seems that terminations and connections are more important with DC

Also, I have two strings. They will see a max of 10a and 7a, so not a huge current load.


Also, on a side note. I got my permission to operate in 3 days! Submitted Monday evening, received the PTO email Wednesday night.

The Unitaps are the correct part for the job. These style connectors are widely used in the industry. The failures and corrosion NewBoston mentioned are due to using the wrong connectors or improper installation. Read the installation instructions, and use the correct torque, and they won't be an issue.

MC4 connectors can only be used if you are still running PV wire. THHN has thinner insulation, so the plastic housing of the connector will not seal to the wire insulation.
If you want a cheaper option, you can just use butt splices. Either insulated, or bare and add heat shrink. Just don't buy the cheap ones you get at the auto parts stores. Many are only rated for 24V. The only problem with crimping is that you would have to cut them out if there is a problem. Just leave yourself a little extra wire in the box.

[Jmal]

Not sure if this is applicable to everybody, but I've found that the 773 wago push nuts and the 221 wago snap nuts (both 600v rated and 221F heat rated) used with a snapnrack nema-3 rated j-box. Their maximum size is #10 awg, perfect for PV wire.

[neweclipse]

DIY sure makes a lot of experts...somewhere is the truth...