Mitsubishi Electric MELSERVO-J3 Series Manual page 355

11. TROUBLESHOOTING
Display Name
A30 Regenerative
error
A31 Overspeed
Definition
Permissible 1. Wrong setting of parameter No.
regenerative power PA02
of the built-in
2. Built-in regenerative resistor or
regenerative resistor
regenerative option is not
or regenerative
connected.
option is exceeded.
3. High-duty operation or continuous
regenerative operation caused the
permissible regenerative power of
the regenerative option to be
exceeded.
Call the status display and check
the regenerative load ratio.
4. Power supply voltage is abnormal.
MR-J3- T:260VAC or more
MR-J3- T1:More than 135VAC
5. Built-in regenerative resistor or
regenerative option faulty.
Regenerative 6. Regenerative transistor faulty.
transistor fault
1) The regenerative option has
2) The alarm occurs even after
Speed has 1. Input command pulse frequency
exceeded the exceeded the permissible
instantaneous instantaneous speed frequency.
permissible speed.
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.PA06, PA07)
5. Encoder faulty.
Cause
Checking method
Checking method
overheated abnormally.
removal of the built-in
regenerative resistor or
regenerative option.
11 - 6
Action
Set correctly.
Connect correctly
1. Reduce the frequency of positioning.
2. Use the regenerative option of larger
capacity.
3. Reduce the load.
Check the power supply
Change the servo amplifier or regenerative
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.