A method for positioning a rotor of a gas turbine automatically is provided that includes gathering data with a control unit, and processing this data to bring the rotor to a desired position which is set according a Human Machine Interface (HMI). The indication of the lay of the rotor to the control unit is done by a key phasor, which includes a sensor which gets a digital pulse for each revolution of a phasor cam wheel. This digital pulse is used to give the information of the lay of the rotor to the control unit.