11-14
11-4 Troubleshooting
OMNUC G5-SERIES AC SERVOMOTOR AND SERVO DRIVE USER'S MANUAL
  11
Troubleshooting and Maintenance
16 0 Overload
When the feedback value for torque 
command exceeds the overload level 
specified in the Overload Detection 
Level Setting (Pn512), overload 
protection is performed according to 
the overload characteristics.
· The load was heavy, the effective 
torque exceeded the rated torque, 
and operation continued too long.
· Vibration or hunting occurred due 
to faulty gain adjustment. The 
Servomotor vibrates or makes 
unusual noise. The Inertia Ratio 
(Pn004) setting is incorrect.
· The Servomotor wiring is incorrect 
or broken.
· The machine load suddenly 
became heavy, e.g., the machine 
hit an object. The machine was 
distorted.
· The electromagnetic brake 
remained ON.
· When multiple machines were 
wired, the wiring was incorrect and 
the Servomotor cable was 
connected to a Servomotor for 
another axis.
Use the analog output or CX-Drive 
and check to confirm that the torque 
(current) waveform oscillates and 
make sure that is does not oscillate 
excessively vertically. Check the 
overload warning display and the load 
rate through communications.
· Increase the capacities of the 
Servo Drive and the Servomotor.
Set longer acceleration and 
deceleration times. Reduce the 
load.
· Readjust the gain.
· Connect the Servomotor cable as 
shown in the wiring diagram. 
Replace the cable.
· Remove the distortion from the 
machine. Reduce the load.
· Release the brake.
· Wire the Servomotor and the 
encoder correctly so that the 
wiring matches the axes.
Refer to 3-2 Overload Characteristics (Electronic Thermal Function) for 
information on overload characteristics.
The connected external regeneration resistance is lower than the minimum 
allowable value (for the minimum allowable value, refer to page 4-56)
Connect a regeneration resistance with a suitable resistance value (for 
external regeneration resistance combinations and resistance values, refer to 
P.4-59)
Alarm 
number
Name Cause Measures
Main Sub