Siemens YASKAWA 840DI Maintenance Manual page 51

Table 3.1 Errors without alarm display (cont'd)
Malfunction
Spindle Motor does Motor rated speed is set
not rotate as specified
incorrectly.
speed.
Speed loop with P
control.
The machine cannot Power supply is turned
be operated after off.
sudden stop during
operation.
Servomotor rotates The connection to the
unstably.
motor is wrong.
Servomotor vibrates The speed loop gain is
at the frequency
excessively high.
around 200 to 400 Hz.
When the motor starts
The speed loop gain is
or stops, the speed excessively high.
overshoot is very
large.
Servomotor The ambient
overheats. temperature is
excessively high.
The surface of
Servomotor is dirty.
The Servomotor is
overloaded.
Spindle Motor Power line from Inverter
generates unusual is disconnected.
noise or vibration.
Motor has imbalance.
3.2 Errors without alarm display and troubleshooting
Cause Check point
Check drive specific
machine data MD6500.
Check signal
"DB3x.DBX21.6
PLC status screen (see
5.2).
Check power supply.
Check the condition of
connectors of the power
cable (U-, V-, and W-
phase) and encoder cable.
Measure the temperature
around the Servomotor.
Visually check the
surface.
Operate the Servomotor
without load.
Check wiring between
Inverter and motor.
Check imbalance of
rotor.
3-5
Remedy
Set MD correctly.
Contact maintenance
"
stuff or machine tool
on
builder to check the
sequence of PLC.
Turn on the power
supply.
Correct the looseness
and other malfunctions
of terminals and
connectors.
Decrease the setting
value for MD3030
(speed loop gain).
Decrease the setting
value for MD3030
(speed loop gain).
Decrease the setting
value for MD3031
(integral time constant).
Lower the ambient
temperature to 40 degree
or below.
Remove the dust and oil
from the motor surface.
Reduce the load or
consider replacement of
new machine with larger
capacity.
Correct the wiring.
Replace the motor.