Patent ID: 7083544

Claim:
A method for monitoring and testing, during operation, the serviceability of a transmission part ( 4 ) arranged for transmission of torque between an electric motor ( 2 ) and a load ( 6 ), said method comprising the steps of: A) monitoring ( 308 ), during normal operation, the torque of the electric motor ( 2 ), B) initiating at least one test sequence if the monitored torque fall below a predetermined value ( 312 ), said test sequence comprising the steps of: setting a rotation speed of the electric motor ( 2 ) at a test rotation speed that differs from the rotation speed of the electric motor ( 2 ) immediately prior to said setting ( 504 , 512 ), and at least logging the torque of the electrical motor ( 2 ) within a period starting from the setting of the rotation speed of the electric motor ( 2 ) and ending when the rotation speed of the electric motor ( 2 ) has reached the test rotation speed ( 506 , 514 ), and C) sending a signal indicating an error ( 522 ) if no further test sequences are to be performed and if said at least one test sequence indicates that said logged torque is below a predetermined value. least one test sequence indicates that said registered time is less than a predetermined value.