Hi, I appreciate the post but I have posted in all those threads you mentioned
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I am looking specifically for a system that maintains my batteries charge connected to the grid, and then when no power from the grid I can use my 12v batteries on my 12v system (Separate than the grid system completely).
I think using a car battery trickle charger may not be the ideal way to keep my batteries ready for usage in winter power-outage.
Since I don't want to do solar (yet) or convert from 12v to 110v I just need a way to keep them charged/ready when power is on
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Also, looking for battery suggestions. I will ONLY be using these to power lights in the house but I could be w/out power for a week at a time.
-Todd