I'm contemplating putting a power feeder on my table saw (10 inch, 3hp) for occasions when I rip a bunch of strips for edging - mostly because I consider a feeder somewhat safer for this sort of repetitive task. I have a 1/2 hp feeder, but should I consider moving up to a full 1 ph model for this task?
Not unless you think the half hp is bogging down, which could be caused by other factors like table needing to be cleaned and lubricated, and or using a dull blade, or too many teeth with the wrong grind.
Those things are geared so low that if everything else is right it should be fine. Doubling the power for more speed on heavy cuts in really hard woods where the feeder needs more power might just overload the saw.
I've bumped into several shops in my area that use power feeders on a table saw; most seemed to be doing architectural work. While I can't tell you the HP on the feeders, I can state that the saws were all either 5 or 7.5 hp.
I'd be wary of over-taxing a 3hp motor if you're planning some kind of production ripping using a feeder.