I have a small project outdoor solar lamp I’m putting together to replace an AC lamp post light we had previously. I have the solar panel, 12 v battery, led lamp, and charge controller wired nicely but I bought a 12v photo controller used for street lamps to put into the lamp line and it has three wires. Red (load), white (neutral), and black (line). Not sure how to wire that in. Any ideas? I apologize for my lack of knowledge on the subject.

Neutral is the 12 volt negative
Line is the 12 volt positive feed (item providing the power)
Load is the 12 volt positive draw (item pulling the power)

Ah, thanks for that!