251
5
TROUBLESHOOTING
Check first when you have a trouble
5.5.3 Drive unit generates abnormal noise
5.5.4 Motor generates heat abnormally
5.5.5 Motor rotates in the opposite direction
5.5.6 Speed greatly differs from the setting
Check
points
Possible Cause Countermeasures
Refer
to
page
Fan
Fan cover was not correctly installed when a cooling fan
was replaced.
Install the fan cover correctly.
Install the fan cover securely with the enclosed fan cover
fixing screws.
260
Check
points
Possible Cause Countermeasures
Refer
to
page
Motor
Motor fan is not working
(Dust is accumulated.)
Clean the motor fan.
Improve the environment.
—
Phase to phase insulation of the motor is insufficient. Check the insulation of the motor. —
Main
Circuit
The drive unit output voltage (U, V, W) are unbalanced.
Check the output voltage of the drive unit.
Check the insulation of the motor.
257
— Motor current is large. Refer to "5.5.11 Motor current is too large" 253
Check
points
Possible Cause Countermeasures
Refer
to
page
Main
Circuit
Phase sequence of output terminals U, V and W is
incorrect.
Connect phase sequence of the output cables (terminal
U, V, W) to the motor correctly
15
The rotation direction of the output shaft is changed by
the reduction gear.
Check the rotation direction of the motor's output shaft. 15
Input
signal
The start signals (forward rotation, reverse rotation) are
connected improperly.
Check the wiring. (STF: forward rotation, STR: reverse
rotation)
18
Adjustment by the rotation speed is improper during the
reversible operation with Pr. 73 Analog input selection
setting.
Check the setting of Pr. 125, Pr. 126, C2 to C7. 132
Parameter
Setting
Pr. 40 RUN key rotation direction selection setting is
incorrect.
Check the Pr. 40 setting. 224
Check
points
Possible Cause Countermeasures
Refer
to
page
Input
signal
Speed setting signal is incorrectly input. Measure the input signal level. —
The input signal lines are affected by external EMI.
Take countermeasures against EMI such as using
shielded wires for input signal lines.
36
Parameter
Setting
Pr. 1, Pr. 2, calibration parameter C2 to C7 settings are
improper.
Check the settings of Pr. 1 Maximum setting, Pr. 2
Minimum setting.
78
Check the calibration parameter C2 to C7 settings. 135
The maximum speed is limited to the maximum speed of
the PM motor (3000r/min).
272
Pr. 31 to Pr. 36 (speed jump) settings are improper. Narrow down the range of speed jump. 79
Load
Stall prevention function is activated due to a heavy
load.
Reduce the load weight. —
Parameter
Setting
Set Pr. 22 Stall prevention operation level higher according
to the load. (Setting Pr. 22 too large may result in
frequent overcurrent trip (E.OC).)
74
Motor Check the capacities of the drive unit and the motor. —
