Abstract: A method for determining an efficiency and/or calibrating a torque of a drivetrain comprises two tests. The drivetrain has a motor-side end at a main shaft connectable to a motor and a generator-side end, with a generator arranged between the ends. In a first test, the motor-side end of the drivetrain is driven. A variable dependent on the main shaft torque is determined at the motor-side end of the drivetrain and an electrical power Pelec is determined at the generator-side end of the drivetrain. In a second test, the generator-side end of the drivetrain is driven and the variable dependent on the main shaft torque is determined at the motor-side end and the electrical power is determined at the generator-side end. An efficiency and/or calibration parameters is/are determined from the electrical power values and the variables dependent on the main shaft torque determined in the first test and second tests.

Abstract: The present application relates to a method for determining an efficiency and/or for calibrating a torque of a drivetrain (1), in particular a drivetrain (1) of a wind turbine. The method for determining an efficiency and/or for calibrating a torque of a drivetrain (1), in particular of a drivetrain of a wind turbine, is particularly suited for carrying out on a test rig and comprises two tests. The drivetrain has a motor-side end at a main shaft connectable to a motor and a generator-side end, between which ends a generator is arranged. In a first test, the motor-side end of the drivetrain (1) is driven. A variable dependent on the main shaft torque is thereby determined at the motor-side end of the drivetrain (1) and an electrical power Pelec is determined at the generator-side end of the drivetrain (1).

Abstract: A mill for grinding rubbish. The mill comprises at least one grinding chamber defined by a side wall and a floor. The mill also comprises at least two rotors and rotatable about respective substantially vertical axes and. Each of the rotors comprises a hub and a plurality of chains connected to the hub and designed to sweep over part of the grinding chamber during rotation of the rotor.

Abstract: A mill for grinding rubbish. The mill comprises at least one grinding chamber defined by a side wall and a floor. The mill also comprises at least two rotors and rotatable about respective substantially vertical axes and. Each of the rotors comprises a hub and a plurality of chains connected to the hub and designed to sweep over part of the grinding chamber during rotation of the rotor.