"PRS 1010, PRS1515, PRS2020, PRS3030 The simplicity  and high performance of the Fangpusun SOLARIX PRS solar charge controller make  it particularly appealing. At the same time, it offers a modern design and a  convenient display, all at an extremely attractive price. Several LEDs in  various colours emulate a tank display, which gives information on the  battery’s state of charge. Here, Fangpusun’s latest algorithms are employed,  resulting in optimal battery maintenance. The Solarix PRS charge controllers  are equipped with an electronic fuse, thus making optimal protection possible.  They operate on the serial principle, and separate the solar module from the  battery in order to protect it against overcharging. For larger  projects, the charge controllers can also be equipped withspecial functions:  e.g. with night light function and selectable charging plateau and  deep-discharge protection voltages." www.fangpusun.com