A surgical cutting and fastening instrument comprises an end effector, a shaft connected to the end effector, and a handle connected to the shaft. The handle comprises an electric, DC motor connected to a drive train for powering the drive train and a plurality of series-connected DC power source connected to the motor for supplying electrical power to the motor. The handle also comprises a power source selection switch for connecting, when in a first state, all of the DC power sources to the motor, and, when in a second state, a subset of the DC power sources to the motor. Also disclosed are means for actuating a RF electrode in the end effector and means for indicating actuation of the RF electrode.