That drum sander you rented was obviously defective. If smoke came from the motor that is the cause of your circuits tripping. The drum sander is specifically made for the project you are doing. When you rent another sander get several different grit belts for it ranging from a medium grit to a fine grit. Never let the drum contact the floor without you moving the machine, to do so will sand a groove in the floor in a tick. Walk backwards pulling the machine at a slow steady pace. Overlap your sanding path with each subsequent pass. Then change the belt to a finer grit and go over it again. Finally useing a floor buffing machine and a screen disc go over it again. To sand the edges of the floor rent an edge sander and basically follow the same procedure. Take it slow, keep the machine moving at all times when in contact with the floor and you should be good to go.