The Prostar PS-15M is the only charge controller for small PV systems that includes a meter, a must to monitor system performance charging current and battery voltage. Its load control feature also helps to save the battery. I was able to connect the Prostar to my battery in parallel with backup charger from the utility line with no problem operating both. This is complete, compact, well-made unit.
I found only one feature lacking that all other small charge controllers lack - the ability to enclose all wiring in conduit or NEMA boxes. I built my system to use a roof-mounted panel to power my home automation & networking electronics in my basement. Because this was installed in a house, the NEC technically requires the wires to be enclosed, which I don't think is really necessary but which the Prostar's mechanical configuration does not permit.
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