I'm a bit late to the party here but I also love my big belt sander/grinder. Mine has a motor that I'd guess to be 2 HP 3 phase. It takes a 4" by 78" belt and it eat material like nothing else I've ever used. I've used it to put a 1" radius on some inch thick steel stock much faster than anything else I could have used and the table makes a square edge and even surface much easier than a hand held or bench grinder.
I get the belts made up for me at Industrial Abrasives.
It stands on a 6" pipe and has the motor and drive wheel on the bottom. Total weight about 200 LB.
The best part is I got it free for the asking when I saw it sitting out on the sidewalk near a repair shop for a few days. That and a Gallmeyer Livingston grinder were soon in the bed of my truck.