Patent ID: 8192239

Claim:
A marine vessel propulsion system comprising: a plurality of propulsion devices, each including a motor and a propeller arranged to be rotated by the motor; a common electric power supply switch arranged to be operated by an operator to turn on and off electric power supplies of the plurality of propulsion devices all at once; an electric power supply control unit arranged to put the electric power supplies of the respective propulsion devices in an on state all at once when the common electric power supply switch is turned on and to put the electric power supplies of the respective propulsion devices in an off state all at once when the common electric power supply switch is turned off; an abnormal state detection unit arranged to detect an abnormal state of each propulsion device; and a power transmission cutoff unit which is arranged to, when an abnormal state of any of the propulsion devices is detected by the abnormal state detection unit, cut off transmission of power between the motor and the propeller of the propulsion device for which the abnormal state is detected.