Thanks for all the help. I did dive in too quickly. My permanent setup in the RV will have fuses and a BMS. And, yes I finally figured out that my meter leads were reversed, duh! Trouble started when I ordered everything at the same time ... the MPP came almost immediately, the batteries took nearly three months, and I am still waiting for the BMS. I made a bad decision to put the batteries together on my bench in order to test the MPP unit. (I assumed if there was a problem with it, I would have a hard time with returns four months after receiving it.) Thanks to all, I will be more careful and so far so good everything works, I learned my lesson the hard way, and everything is back on track.