9 - 10
9. TROUBLESHOOTING
Display
Name
Definition
Cause
Action
1. Machine struck something.
1. Review operation pattern.
2. Install limit switches.
2. Wrong connection of servo motor.
Servo amplifier's output terminals
U, V, W do not match servo
motor's input terminals U, V, W.
Connect correctly.
3. Servo system is instable and
hunting.
1. Repeat acceleration/
deceleration to execute auto tuning.
2. Change auto tuning response setting.
3. Set auto tuning to OFF and make gain
adjustment manually.
A. 51
Overload 2
Machine collision or
the like caused max.
output current to
flow successively for
several seconds.
Servo motor locked:
1s or more
4. Encoder faulty.
When the servo motor shaft is
rotated slowly with the servo off,
the cumulative feedback pulses
should vary in proportion to the
rotary angle. If the indication
skips or returns midway, the
encoder is faulty.
Checking method
Change the servo motor.
1. Acceleration/deceleration time
constant is too small.
Increase the acceleration/deceleration
time constant.
2. Torque limit value (parameter
No.28) is too small.
Increase the torque limit value.
3. Motor cannot be started due to
torque shortage caused by power
supply voltage drop.
1. Review the power supply capacity.
2. Use servo motor which provides larger
output.
4. Position control gain 1 (parameter
No.6) value is small.
Increase set value and adjust to ensure
proper operation.
5. Servo motor shaft was rotated by
external force.
1. When torque is limited, increase the
limit value.
2. Reduce load.
3. Use servo motor that provides larger
output.
6. Machine struck something.
1. Review operation pattern.
2. Install limit switches.
7. Encoder faulty
Change the servo motor.
A. 52
Error excessive Droop pulse value of
the deviation
counter exceeded
80k pulses.
8. Wrong connection of servo motor.
Servo amplifier's output terminals
U, V, W do not match servo
motor's input terminals U, V, W.
Connect correctly.
