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9. TROUBLESHOOTING
Display Name Definition Cause Action
1. Mismatch between used
regenerative brake option and
parameter No. 2 setting
Set correctly.
2. Built-in regenerative brake
resistor or regenerative brake
option is not connected.
Connect correctly
3. High-duty operation or continuous
regenerative operation caused the
permissible regenerative power o f
the regenerative brake option to
be exceeded.
Checking method
Call the status display and check
the regenerative load ratio.
1. Reduce the frequency of positioning.
2. Use the regenerative brake option of
larger capacity.
3. Reduce the load.
4. Power supply voltage is abnormal.
MR-J2S- B:260VAC or more
MR-J2S- B1:135VAC or more
Review power supply
Permissible
regenerative power
of the built-in
regenerative brake
resistor or
regenerative brake
option is exceeded.
5. Built-in regenerative brake
resistor or regenerative brake
option faulty.
Change servo amplifier or regenerative
brake option.
30 Regenerative
alarm
Regenerative
transistor fault 6. Regenerative transistor faulty.
Checking method
1) The regenerative brake option
has overheated abnormally.
2) The alarm occurs even after
removal of the built-in
regenerative brake resistor or
regenerative brake option.
Change the servo amplifier.
1. Small acceleration/deceleration
time constant caused overshoot to
be large.
Increase acceleration/deceleration time
constant.
2. Servo system is instable to cause
overshoot. 1. Reset servo gain to proper val ue.
2. If servo gain cannot be set to proper
value:
1) Reduce load inertia moment ratio; or
2) Reexamine acceleration/
deceleration time constant.
31 Overspeed Speed has exceeded
the instantaneous
permissible speed.
3. Encoder faulty. Change the servo motor.
1. Short occurred in servo amplifier
output phases U, V and W. Correct the wiring.
2. Transistor of the servo amplifier
faulty.
Checking method
Alarm (32) occurs if power is
switched on after U,V and W
are disconnected.
Change the servo amplifier.
3. Ground fault occurred in servo
amplifier output phases U, V and
W.
Correct the wiring.
32 Overcurrent Current that flew is
higher than the
permissible current
of the servo
amplifier.
4. External noise caused the
overcurrent detection circuit to
misoperate.
Take noise suppression measures.
Current higher than
the permissible
current flew in the
regenerative brake
transistor.
(MR-J2S-500B only)
5. Improper wiring of the
regenerative brake option. Wire the regenerative brake option
correctly.