This Works for me as a manual transfer switch, I have solar input on 1, and grid power on 2, the output goes to the RV. I can switch from one or the other swiftly enough so some electronic device I have doesn't shut off. However, I wasn't sure just how to place the wireing on the screw terminals on this from looking at the switch, or even using an ohm meter, fortunately there was a review on this switch listing that shows where to place wires, and that worked. So far the switch has no problems rSee full review