Operation   
8.2 Faults 
  1FT7 synchronous motors 
44  Operating Instructions, 04/2010, 610.40075.40b 
8.2  Faults 
 
 
Note 
Damage to the machine caused by faults 
Correct the cause of the fault as specified in the remedial measures section. Repair any 
damage to the machine/motor. 
 
 
Note 
When operating the motor with a converter, refer also to the operating instructions of the 
frequency converter if electrical faults occur. 
 
If there are deviations from normal operation or if faults occur, initially proceed according to 
the following list. In this regard, observe the relevant chapters in the documentation 
associated with the components of the complete drive system. 
Even in test operation, never disable protective functions or devices. 
Table 8- 1  Possible faults 
Fault  Cause of fault (see key table) 
Motor does not start up  A  B                                
Motor starts up slowly  A    C   F                          
Humming noise when starting       C   F                          
Humming noise during operation  A    C   F                          
Overheating during no-load operation        D   G H I                   
Overheating when under load  A    C     G H I                     
Overheating of individual  
winding sections 
        F                          
Uneven running                  J  K                  
Grinding sound, running noise                       L               
Radial vibrations                   M N O P  R 
Axial vibrations                            O    Q R  
Water is leaking                                    S