So this is what the deal was...and let me preface it by saying that I feel like an idiot, especially since I work in the tech industry lol.
We're in Florence, OR, right now, which is known for its sand dunes. We'd been out and about quite a bit and I think some fine grains of sand ended up making its way into several of our charging cables. It was too fine to see, even with a high powered flash light. Apparently the contacts on the Galaxy S3 and Note 4 are much more sensitive than the S5, which is why my wife's phone was still charging and the other 2 weren't.
I guess it was just an extreme coincidence that they both reached the tipping point the same evening I connected the UPS.
So @ducttape, I owe you an apology for this:
jayspi wrote:
Ductape wrote:
At work we had a lot of problems with bad contacts on the end of cheap micro USB cords. Try a new cable.
I'm 99% sure it's not the contacts. I shouldn't have that problem on 2 chargers at once, and it also wouldn't explain why one phone charges off the 3rd charger and the other doesn't. Unless the contacts went bad and the charger in the phone got dirty / went bad at the same time. That's just too coincidental...
After many years in the tech industry I've learned that it's best sometimes to just admit that you were wrong, and I was :)
But during this process I learned a lot about electrical systems in an RV, so it's a definite win. I used to get stressed about all this stuff until I learned to treat it all as a learning experience.
Thanks to all of you for your help!
