Is there any charge controller that will allow me to charge the bat
teries when I have the sun out and when it is dark/cloudy charge using th
e grid power. I have a Prosine 1800W inverter and I would like to use it as
a UPS. The battery bank is charged by solar and I want to make sure that
it is always charged either using PV or the grid power. So I was wonder
ing if there was a charge controller that took in as inputs grid and PV. I
would appreciate any help on this. Thanks.