It also sounds to me like you might be trying to take too big a bite on each pass. The tripped breaker and the feed stalling are clues. I don't know about that particular machine but my 16" King has a steel feed roller in front of the head and a rubber roller past that head. I've replaced the rubber roller and I may be in need of replacing the steel one or trying to resharpen the edges on it. It resembles a gear and after 1000s of board feet the edges on it may be getting dull and losing their grip but you shouldn't be having that issue yet if your machine is fairly new.