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9. TROUBLESHOOTING
Display
Name
Definition
Cause
Action
(Note 2)
Alarm details
AL.51 Overload 2
Machine collision
or the like caused
a continuous
maximum current
for a few seconds.
1. Driver fault.
<Checking method>
The servo motor is disconnected on
the machine side and then the servo
motor is test-operated. The alarm
(AL.51) does not occur. (Check after
setting the gain to the initial value.)
Change the driver.
2. The servo system is instable and
causes oscillation or hunting.
1. Repeat acceleration/
deceleration to execute
auto tuning.
2. Change the auto tuning
response setting.
3. Set auto tuning to OFF
and make gain
adjustment manually.
4. Check that the coupling
with the servo motor shaft
is not loose.
3. Machine struck something.
1. Check operation pattern.
2. Install limit switches.
3. Check that the
electromagnetic brake is
not applied.
4. Incorrect connection of servo motor.
Driver 's output terminals U, V, W do
not match servo motor's input
terminals U, V, W.
Connect correctly.
5. Encoder fault.
<Checking method>
When the servo motor shaft is rotated
with the servo off, the cumulative
feedback pulses do not vary in
proportion to the rotary angle of the
shaft but the indication skips or returns
midway.
Change the servo motor.
6. A power cable is disconnected.
Repair the cable.
7. Servo motor fault.
Change the servo motor.
