Strange behavior today w/ TWO 200W panels wired in parallel

[TT_Vert]

This is on my RV.

I'm just looking for opinions. The problem is resolved but I'm trying to wrap my head about this as the behavior doesn't make sense. I noticed in my solar app that I was only seeing about 12V fed into my MPPT  controller and no current into the batteries. Battery SOC was near 40% so i knew something was wrong. I have a triron 3210N MPPT and two 200W panels wired in parallel so I should see about 22V and at least SOME current today. I checked my other array for my shed and it was putting out power so i knew I should be seeing something.

I took my DVOM and noticed that when I turned OFF the breaker between the panels and the charge controller I would see 24V from the panels but the second I turned the solar feed back on to the MPPT it dropped to 12V and still no current. Turns out one of my two panels' positive plugs was loose. But given my panels are wired in parallel, shouldn't one panel have still been providing current and 22ish V? Why would this occur when it was loaded only?

Thanks much,

Dave

[thm_w]

Doesn't really make sense unless one panel is bad or was very shaded.
Or the loose connection was not where you thought and affected both panels.

Do a short circuit current comparison between the two maybe?

[TT_Vert]

Neither panel was shaded, and the loose connection was certainly at that positive wye into the MPPT controller.   It was loose and as soon as i clicked it back in I was back in business.  I saw 300W on my 400W of panels right away.   It just doesn't make sense to me.

Dave

[TT_Vert]

Anyone else have any opinion?

[TT_Vert]

One last chance at getting input from the experts. 

Dave

[Poroit]

I suggest it was just a glitch in your Solar App due to the type of fault.

Imagine the scenario that the controller was trying to deal with.

A loose positive terminal with the available current capacity changing every time your RV hit a bump in the road.

I doubt the designers ever allowed for that type of scenario.

[TT_Vert]

 I don't understand what scenario the MPPT was dealing with that's just it.  The panels were wired in parallel so even if one didn't have one lead connected I should have been getting 24V and a max of 200 W from the one connected panel i'd assume.  That's where my confusion comes in.
Dave