Oztules, The videos show diodes but I will check for them anyway. Good point.
Ghurd, that looks like a plastic junction box available at major US DYI retailers. I wondered if that would work. J-boxes on flee-bay are about $10 per box. The non-acid silicon should not have the acetic acid (vinegar) smell. Correct me if I'm wrong.
I did NOT watch any of the videos.
There is no gain to be had with bypass diodes in a non-MPPT 12 or 24V system. If I install PVs that the factory put bypass diodes in, I cut the diodes out to save returning later to do it after they failed.
Blocking diodes, maybe, but it depends on the situation, system, and controller, so I'd say use blocking diodes.
Not much potential for causing a problem, and they won't hurt anything in a decent system.
J-box.
If this was my project...
I would use a plastic box that is UV-resistant ("outdoor rated"), with a flat back.
I'd get a plan in place depending on how and where the PV conductors were, what terminal strip was available, and attack the back of the box with a Dremmel tool.
After a trail fitting, then I'd start by making the permanent electrical connections, more trial fitting, more planing, etc...
THEN I'd actually cut open the silicone.
It takes a LOT of silicone, so don't expect a tube will make 5 PVs.
Remember, there WILL be air moving between inside & outside of the J-box. Nothing you can do about that.
Keep the PV side of the J-box completely sealed to keep water out, natuarally.
But the moving air will cause condensation inside the box, and it would be best if that water could drain out.
I seal the high side, both side sides (?), and in about 25% of the way from the sides on the bottom side.
It leaves a place for the water to get out, but nowhere for the water to get in.
If the J-box has an O-ring gasket, cut out 1" in the center of the bottom side.
If it does not have an O-ring, silicone 3 and a half sides of the lid (you know what I mean).
Works for me.
"The non-acid silicon should not have the acetic acid (vinegar) smell. Correct me if I'm wrong."
You are correct.
The non-acid stuff is not at all offensive to me.
Smelling the acid stuff makes every sphincter in my being contract violently and uncontrollably.
The non-acid stuff takes a few hours before it can be exposed to water, and it costs more, so start looking at the expensive end of the caulking compound.
I would not use wood for the frame, ever. Wood warps.
Aluminum angle stock is cheap enough. Cheaper than wood here (by the foot, in context).
Mono vs Poly?
3 main arguements.
"Mono is more efficient" yet I have bought poly of the same size with 20% greater output ratings than monos of the same or smaller size.
"Mono is less fragile" yet I have seen more than a couple polys with shattered or broken to the point of 'gone' front glass still producing rated power (I do not expect they maintained it for long, but they did it when I was there).
"Poly is less expensive per rated watt" yet I have (many times) purchased larger monos of the same brand and model for less $/W than the mono counter parts.
To me, it all comes down to cost per amp into the battery under the conditions when the customer needs it the most...
And the reliability. So no amorphous PVs.
G-