is there any way to adjust the photocell sensitivity? I mounted mine in the garage and it doesn't recognize it's daytime during overcast or cloudy days
Someone will correct me if I’m wrong but I don’t believe that’s possible. I think you’ll need to mount the transformer closer to a window or use a photocell extension cable.
When desiring dusk/dawn capabilities from a transformer mounted inside of a garage, we typically recommend considering a low-voltage photocell extension cord like mesodude mentioned. The light-sensing diode will get the most accurate readings being outdoors in mostly direct sunlight.