But, it does work for charging a battery.
This means any load, even a small parasitic load, could over-discharge the battery if the USB ports are used and the battery is not being charged regularly.
The task I'm using it for does not require the USB ports, but I am disappointed that they are not able to be used in production due to the over discharge problem.
I paired it with a $60 weather-proof solar panel to charge a 12-v car battery that I use to power lights in my outdoor shop.
It does the job and shows the status of the power output of my solar panels as well as the battery.
I am not too sure on this display very small instructions indicate you may damage unit unless their hookup sequence is followed exactly wiring will be exposed to the outside as the unit is surface mounted connections are visible as installed pay a little more and get a unit that is back wired and looks like it was done professionaly installed.
This worked 2 months and stopped.
This controller sends way too much voltage to the batteries and electronics.
I thought it was a bad unit so I bought another one and got the same voltages.Spend the extra $15 and get one from a reputable company like Renogy.
2nd never worked.