Determining start time for three-phase cage induction motors that drive belt transport conveyers

The paper establishes the analytical relationship of the start time for a work machine with constant torque resistance driven by a three-phase cage induction motor powered directly from the grid. The medium torque of the induction motor was obtained by integrating the simplified Kloss formula from the natural mechanical characteristic of the driving motor. It is used the medium torque of the motor, the reduce resistance torque at the shaft, the reduced moment of inertia and the speed of the motor for horizontal and inclined belt transport conveyers, without and with deviation drums.