Most of rotor related faults in three-phase induction motors are due to broken rotor bars and end-ring defects. Nowadays Inductions motors are more frequently used with inverters which make the diagnosis process more complicated. Furthermore, some manufacturers of induction machines mount converters (i.e. rectifier and inverter) directly onto the machine, which makes the stator current unattainable for diagnosis. In order to overcome these drawbacks, the authors propose to analyze new motor fault signatures in the supply line current of the inverter. Experimental and simulation results show a total agreement and confirm the effectiveness of the present study.