Mitsubishi Electric MELSERVO-J4 Instruction Manual Trouble Shooting page 74

1. TROUBLESHOOTING
Description
The servo motor does not
operate.
The speed of the servo
motor or linear servo motor
is not increased. Or the
speed is increased too
much.
The servo motor vibrates
with low frequency.
Possible cause
The axis is disabled.
An error is occurring on the
servo system controller side.
The setting of a servo
parameter is incorrect on the
servo system controller side.
The position command is not
inputted correctly.
The connection destination
of the encoder cable is
incorrect.
The setting of the speed
command, speed limit, or
electronic gear is not correct.
The connection of the servo
motor is incorrect.
The voltage of the main
circuit power supply has
dropped.
For a servo motor with an
electromagnetic brake, the
brake has not released.
The selection of SP1 (Speed
selection 1), SP2 (Speed
selection 2), or SP3 (Speed
selection 3) is incorrect for
the speed control or torque
control.
The estimated value of the
load to motor inertia ratio by
auto tuning is incorrect.
When the load to motor
inertia ratio is set by manual,
the setting value is incorrect.
The command from the
controller is unstable.
Torque or thrust during
acceleration/deceleration is
overshooting exceeding the
limit of the servo motor when
the motor stops.
The servo gain is low. Or the
response of auto tuning is
low.
Check result
Check if the disabling control
axis switch is on.
[B]: SW2-2
[WB]: SW2-2 to 4
Check if an error is occurring
on the servo system
controller side.
Check the settings of servo
parameters on the servo
system controller side.
Check cumulative command
pulses using MR
Configurator2 and check if
numerical values are
changed by inputting the
command.
Check if the connection
destinations of CN2A, CN2B,
and CN2C are the same as
CNP3A, CNP3B, and
CNP3C.
Check the settings of the
speed command, speed limit,
and electronic gear.
Check the wiring of U, V, and
W.
Check if the voltage of the
main circuit power supply
dropped.
Check the power supply of
the electromagnetic brake.
Check SP1 (Speed selection
1), SP2 (Speed selection 2),
and SP3 (Speed selection 3)
if the selected speed
command is correct.
If the servo motor may be
driven with safety, repeat
acceleration and
deceleration several times to
complete auto tuning. Check
if the load to motor inertia
ratio is proper compared with
the actual ratio for manual
setting.
Check the command from
the controller.
Check the effective load ratio
during
acceleration/deceleration if
torque/thrust exceeds the
maximum torque/thrust.
Check if the trouble is solved
by increasing auto tuning
response ([Pr. PA09]).
1 - 67
Action
Turn off the disabling control
axis switch.
Cancel the error of the servo
system controller.
Review the setting of the
servo parameter on the
servo system controller side.
Review the setting of the
servo system controller and
the servo program.
Connect encoder cables
correctly.
Review the settings of the
speed command, speed limit,
and electronic gear.
Connect it correctly.
Increase the voltage of the
main circuit power supply.
Turn on the electromagnetic
brake power.
Review the settings of SP1
(Speed selection 1), SP2
(Speed selection 2), SP3
(Speed selection 3), and
speed command.
Execute auto tuning and
one-touch tuning to reset the
load to motor inertia ratio.
Set the load to motor inertia
ratio correctly for manual
setting.
Review the command from
the controller.
Check the cable for
command if there is failure
such as disconnection.
Reduce the effective load
ratio by increasing
acceleration/deceleration
time and reducing load.
Adjust gains.
Target
[B]
[WB]
[WB]
[A]
[B]
[WB]
[RJ010]
[A]
[A]
[B]
[WB]
[RJ010]