A surgical instrument is disclosed, the instrument including: a handle assembly (100) ； a jaw assembly (304) including a staple cartridge (308) containing a plurality of staples and an anvil (308) to form the plurality of staples upon firing； a lockout mechanism (373) configured to prevent reuse of the jaw assembly； a drive assembly (118, 120, 122) at least partially located within the handle and connected to the jaw assembly； a motor (164) operatively coupled to the drive assembly； and a controller (406) operatively coupled to the motor, the controller configured to control supply of electrical current to the motor and to monitor a current draw of the motor, wherein the controller is further configured to terminate the supply of electrical current to the motor in response to a drop in the current draw.
