I have a fuse box that is tapped directly into the li-ion battery. "Tapped" is a strong word. I have a 16G wire that I stripped approximately 4" and wrapped it around the post many times, then forced the cap back on. I heard others (maybe upthread?) who drilled into that post. This post is definitely always on. As far as amperage, I don't know. Since it is directly off the battery, I can't imagine you will find more than this elsewhere.