Appendix 2.16.3.5 Troubleshooting The Spindle System When There Is No Alarm Or Warning - Mitsubishi Electric C70 Setup Manual

Appendix 2.16.3.5 Troubleshooting the spindle system when there is no alarm or warning

If an abnormality is observed in the spindle system but no alarm or warning has occurred, refer to the following table and
check the state.
[1] The rotation speed command and actual rotation speed do not match.
Investigation item
Check the commanded speed and the spindle
1 rotation speed displayed on the drive monitor
screen.
Check whether there is slipping between the
2 motor and spindle. (When connected with a belt
or clutch.)
Check the spindle parameters (SP026, SP129
3
and following).
[2] The acceleration/deceleration time is long or has increased in length.
Investigation item
Check whether the friction torque or load inertia
1
has increased.
Check if there is any abnormality in the motor's
2
rotation during coasting.
Check whether the torque limit signal has been
3
input.
[3] The motor stops during cutting.
Investigation item
Check the load rate (load meter value) during
1
cutting.
2 Carry out the same investigations and remedies as section (4).
[4] The vibration and noise (gear noise), etc., are large.
Investigation item
Check the machine's dynamic balance. (Coast
1
from the maximum speed.)
Check whether there is a resonance point in the
2
machine. (Coast from the maximum speed.)
3 Check the machine's backlash.
Change the setting of the speed loop parameter
4
(SP005:VGN1).
Jiggle the detector connectors (drive unit side
5 and detector side) and check if they are
disconnected.
Turn the power OFF, and check the connection
6
of the speed detector cable with a tester.
[5] The spindle coasts during deceleration.
Investigation item
When connected with a belt or clutch, check
1 whether there is slipping between the motor and
spindle.
Investigation results
The speed command is not input correctly.
The speed command is correct.
There is slipping.
No particular problems found.
The correct values are not set.
The correct values are set.
Investigation results
The friction torque has increased.
No particular problems found.
The bearings do not rotate smoothly.
The bearings rotate smoothly.
The signal has been input.
The signal is not input.
Investigation results
The load meter sways over 120% during
cutting.
No particular problems found.
Investigation results
The same noise is heard during coasting.
No particular problems found.
Vibration and noise increase at a set rotation
speed during coasting.
No particular problems found.
The backlash is great.
No particular problems found.
The vibration and noise are lost when the
setting value is lowered by approx.100.
The symptoms do not change even if the
above value is set.
The connection is loosened.
The connector fixing is normal.
The connection is faulty or disconnected.
The connection is normal.
Investigation results
There is slipping.
No particular problems found.
C70 Setup Manual
Appendix 2.16 Troubleshooting
Remedies
Input the correct speed command.
Check the investigation item No. 2.
Repair the machine side.
Check the investigation item No. 3.
Set the correct values.
Replace the spindle drive unit.
Remedies
Repair the machine side.
Check the investigation item No. 2.
Replace the spindle motor.
Check the investigation item No. 3.
Release the input signal.
Replace the drive unit.
Remedies
Reduce the cutting amount.
Check the investigation item No. 2.
Remedies
Repair the machine side.
Check the investigation item No. 2.
Repair the machine side.
Check the investigation item No. 3.
Repair the machine side.
Check the investigation item No. 4.
Change to the setting value.
(Note) The impact response will drop.
Return the setting values to the original values.
Check the investigation item No. 5.
Correctly connect the connector.
Check the investigation item No. 6.
Replace the detector cable.
Correct the connection.
Replace the drive unit.
Remedies
Check the machine side and repair it.
Replace the drive unit.
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