Mitsubishi Electric MELSERVO MR-J2S- A Instruction Manual page 202

10. TROUBLESHOOTING
Display Name
AL.25 Absolute
position erase
AL.30 Regenerative
alarm
AL.31 Overspeed
Definition
Absolute position 1. Reduced voltage of super capacitor
data in error in encoder
2. Battery voltage low
3. Battery cable or battery is faulty.
Power was switched 4. Super capacitor of the absolute
on for the first time position encoder is not charged
in the absolute
position detection
system.
Permissible 1. Wrong setting of parameter No. 0
regenerative power
2. Built-in regenerative brake
of the built-in
resistor or regenerative brake
regenerative brake
option is not connected.
resistor or
3. High-duty operation or continuous
regenerative brake
regenerative operation caused the
option is exceeded.
permissible regenerative power of
the regenerative brake option to
be exceeded.
Call the status display and check
the regenerative load ratio.
4. Power supply voltage is abnormal.
MR-J2S- A:260VAC or more
MR-J2S- A1:135VAC or more
5. Built-in regenerative brake
resistor or regenerative brake
option faulty.
Regenerative 6. Regenerative transistor faulty.
transistor fault
1) The regenerative brake option
2) The alarm occurs even after
Speed has exceeded 1. Input command pulse frequency
the instantaneous exceeded the permissible
permissible speed. instantaneous speed frequency.
2. Small acceleration/deceleration
time constant caused overshoot to
be large.
3. Servo system is instable to cause
overshoot.
4. Electronic gear ratio is large
(parameters No. 3, 4)
5. Encoder faulty.
Cause
Checking method
Checking method
has overheated abnormally.
removal of the built-in
regenerative brake resistor or
regenerative brake option.
10 - 9
Action
After leaving the alarm occurring for a few
minutes, switch power off, then on again.
Always make home position setting again.
Change battery.
Always make home position setting again.
After leaving the alarm occurring for a few
minutes, switch power off, then on again.
Always make home position setting again.
Set correctly.
Connect correctly
1. Reduce the frequency of positioning.
2. Use the regenerative brake option of
larger capacity.
3. Reduce the load.
Review power supply
Change servo amplifier or regenerative
brake option.
Change the servo amplifier.
Set command pulses correctly.
Increase acceleration/deceleration time
constant.
1. Re-set servo gain to proper value.
2. If servo gain cannot be set to proper
value:
1) Reduce load inertia moment ratio; or
2) Reexamine acceleration/
deceleration time constant.
Set correctly.
Change the servo motor.