Mitsubishi Electric Melservo-J3 Series MR-J3-B, Instruction Manual

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16. INDEXER POSITIONING OPERATION
Description Check method Possible cause Action
In absolute
position detection
system, a
restored position
deviates at power
restoration. For the geared servo motor,
check the setting of the electronic
gear (parameter No.PA06 and
PA07). The reduction ratio is not calculated
correctly. Check the setting of the reduction
ratio.
The command position and the
current position do not match. The maximum speed at power failure
(3000r/min) exceeded when the servo
amplifier power supply is OFF. Check the machine components so
that the servo motor does not rotate at
the speed of 3000r/min or more while
the power supply is OFF.
Overshoot/under
shoot occurs. 1. Check the velocity waveform
with "Graph" command of
"Monitor" menu on MR
Configurator, and check if
overshoot/undershoot is
occurring.
2. If the servo motor can be driven
safely, repeat acceleration and
deceleration three times or
more to complete auto tuning.
1. The servo gain is low or too high.
2. The auto tuning response is low or too
high.
Adjust the auto tuning response, and
readjust the gain. (Refer to chapter 9.)
Check if the maximum torque
exceeds the torque limit value.
1. Check the "instantaneous
torque" in the status display.
2. Check the torque ripple with
"Graph" command of "Monitor"
menu on MR Configurator.
The maximum torque is insufficient.
1. Shortage of servo capacity.
2. Too large load. 1. Reduce the load by changing the
mass and shape of the workpiece.
2. Reduce the effective load ratio by
increasing acceleration/deceleration
time.
The setting of the torque limit is
incorrect.
(Set with parameter PA11, PA12, PC35.) Review the torque limit setting.
Check if there is a backlash on
the machine part. There is a backlash between the servo
motor and the machine (such as a gear
and coupling). Adjust the backlash on the coupling
and the machine part.
Communication
with the servo
amplifier fails
using MR
Configurator. Check if they are on-line. They are off-line. Set them to on-line.
Select "on-line" in the system setting of
the "Set-up" menu.
Check if the communication cable
has any failure such as damage. Communication cable fault. Change the communication cable.
Check the communication
settings, such as the baud rate
and ports.
Check with "system setting"
command of "Set up" menu.
The communication setting is incorrect. Set the communication correctly.
Check if the model selection is set
correctly.
Check with "system setting"
command of "Set up" menu. The model being connected differs from
the model set in the model selection. Set the model setting correctly.
In the device manager on the
personal computer, check if
"MITSUBISHI MELSERVO USB
Controller" is being displayed
under the USB (Universal Serial
Bus) controller. The driver is not set correctly. Delete an unknown device or other
devices, cycle the power of the servo
amplifier, and then set the driver again
according to Found New Hardware
Wizard.
For details, refer to Help of MR
Configurator.