Niner it is all your fault I got this thing! :) The manual says in one place it has an adjustable high set point and in another that it has an adjustable float voltage. In real life, it seems there is only the one adjustable voltage for when it stops charging (high set point)
http://www.chinasolarregulator.com/user-manual/solar30.pdfWhatever, I am not sorry I got this. I don't even care if it is shunt instead of series. I had a shunt one before and it did the job just fine. You can way over-do the fancy stuff in this racket.
BTW there is a Youtube that Russian guy uploaded I linked some time ago that shows how to push the buttons. Came up on Google.
https://www.youtube.com/watch?v=EOw-ZxYJJ2QHe also has the RJ special so you can see how big the Solar 30 is.