108 BBV28581 05/2010
Diagnostics and Troubleshooting
Fault detection codes that cannot be cleared automatically (continued)
Code Name Possible causes Remedy
OCF Overcurrent Parameters in the Motor control
menu drC- page 57 are not
correct
Inertia or load too high
Mechanical locking
Check the parameters
Check the size of the motor/drive/load
Check the state of the mechanism
Connect line chokes
Reduce the Switching frequency SFr
page 59
Check the ground connection of drive, motor
cable and motor insulation.
SCF1 Motor short circuit Short-circuit or grounding at the
drive output
Ground fault during running status
Commutation of motors during
running status
Significant current leakage to
ground if several motors are
connected in parallel
Check the cables connecting the drive to the
motor, and the motor insulation
Connect motor chokes
SCF3 Ground short circuit
SCF4 IGBT short circuit Internal power component short
circuit detected at power on
Contact your local Schneider Electric
representative
SOF Overspeed • Instability
Overspeed associated with the
inertia of the application
Check the motor
Overspeed is 10% more than Maximum
frequency tFr page 57 so adjust this
parameter if necessary
Add a braking resistor
Check the size of the motor/drive/load
Check parameters of the speed loop (gain
and stability)
tnF Auto-tuning Motor not connected to the drive
One motor phase loss
Special motor
Motor is rotating (being driven by
the load, for example)
Check that the motor/drive are compatible
Check that the motor is present during auto-
tuning
If an output contactor is being used, close it
during auto-tuning
Check that the motor is completely stopped