11-26
11-4 Troubleshooting
OMNUC G5-SERIES AC SERVOMOTOR AND SERVO DRIVE USER'S MANUAL
  11
Troubleshooting and Maintenance
Vibration is occurring 
at the same 
frequency as the 
power supply.
Inductive noise is occurring. Check to see if the drive control signal 
lines are too long.
Shorten the control signal lines.
Check to see if the control signal lines 
and power supply lines are not bound 
together.
· Separate control signal lines 
from power supply lines.
· Use a low-impedance power 
supply for control signals.
The position is 
misaligned.
(Position 
misalignment occurs 
without an alarm 
being output.)
There is an error in the coupling 
of the mechanical system and 
the Servomotor.
Check to see if the coupling of the 
mechanical system and the Servomotor 
is misaligned.
Correct the coupling between the 
mechanical system and the 
Servomotor.
· Noise is entering on the error 
counter reset (ECRST) 
input.
· Noise is entering on the 
position command pulse 
(CW and CCW) inputs.
Check to see if the control signal lines 
and power supply lines are bound 
together.
Separate the control signal lines 
from the power lines or take other 
measures against noise.
Check to see if it is a shielded twisted-pair 
cable with core wires that are at least 0.08 
mm dia.
Use a control I/O signal cable that 
meets specifications.
Check the length of the control I/O signal 
cables.
Do not allow the length of the 
control I/O signal cables to 
exceed 10 m for a line driver input 
and 3 m for an open-connector 
input.
The gain is wrong. − Perform manual tuning.
The load inertia is large.
Inspect the following.
· Is the load too large?
· Is the motor rotation speed too high?
· Adjust the gain.
· Review the load conditions, 
and replace the Servomotor 
and Servo Drive with 
appropriate models.
Symptom Probable cause Items to check Measures