Just wanna make sure I'm doing this right...

[MadScientist267]

Top: Virgin junction box.




Bottom: How I believe I'm supposed to connect. Squeeze around the wire and then solder?




Steve

[MadScientist267]

Quick update... That's how I did it, and no problemo...

Steve

[ghurd]

Yes.

What is it, and what is it for?
Guessing a solar panel for a 12V system?
Get that bypass diode out of there before it causes issues.  It won't do any good in a system like what I think it is going into.

Strange panel.  Most have a center tap and 2 bypass diodes.
G-

[MadScientist267]

Yeah you're probably right...

They're 12V each, set of 4, two 24V strings in parallel, then fed to MPPT for a 12V system.

The gains I'd get in a bypass scenario are likely minimal. I want to try them in a 48V string too, but I guess there still would be little bypassing action since they sit in a square together.

Lots of problems with the diodes? O.o

Steve

[ghurd]

Lots of problems with the diodes? O.o

More than there should be... all things considered?

I do not quite understand WHY they would fail in a 12V system with the panel 100V ~ 1000V bypass diodes over 6V sections.
But one summer I changed (removed) a lot of them.  Different brands and types of panels, sizes, diodes, ages, controllers, installers, etc.
Still come across a bad one every so often, but not so common since now I remove them at the start.

If one of the 2 fails to short, or if the situation is such that a section is being bypassed, that only leaves 10Vopen in a 12V system.
I see no use for them in a "typical normal" 12V system, so I remove them.
G-

[rossw]

I monitor the array current (6 modules in series per array), for each of my (presently) 6 arrays.
It's a good, quick, reliable way to know if there's a problem with a panel or tracker - because one is suddenly low.
Combined with a pyranometer, it's a good way to tell when your arrays need cleaning too

[MadScientist267]

Ok so that's a "ditch em" if I'm interpreting right then?

Steve

[rossw]

Ok so that's a "ditch em" if I'm interpreting right then?

If you're referring to  my comment, it's definately NOT saying that. I have the diodes in mine - and when I did (through an act of foolish haste) blow all the diodes in one array - I replaced them ALL before reinstalling and re-connecting them.

They're there for a reason, and the higher the voltage, the more critical they are IMHO.

[ghurd]

They're there for a reason, and the higher the voltage, the more critical they are IMHO.

I agree with that.
6 modules in series, with 12 bypass diodes, and if one is bypassing I can see how that helps.

One 12V 50W or 80W panel and a PWM controller?  I do not see any advantage to them.

I still don't know what would cause them to fail in a single panel <100W 12V system.
G-

[MadScientist267]

 I'll hold off for now, they're not in an impossible location, so if one goes, I can get to them relatively easy.

With the MPPT, the meter disagreeing with my eyes will tell me if I have a problem to look into.

 I'll keep it in mind tho.

Steve