165
Check first when you have a trouble
5.6.4
Motor generates heat abnormally
5.6.5
Motor rotates in the opposite direction
5.6.6
Speed greatly differs from the setting
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 inverter output voltage (U, V, W) are
unbalanced.
Check the output voltage of the inverter.
Check the insulation of the motor.
Parameter
Setting
The
Pr. 71 Applied motor
setting is wrong.
Check the
Pr. 71 Applied motor
setting.
—
Motor current is large.
Refer to "5.6.8 Motor current is too large"
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.
Input
signal
The start signals (forward rotation, reverse rotation)
are connected improperly.
Check the wiring. (STF: forward rotation , STR:
reverse rotation)
The polarity of the frequency command is negative
during the polarity reversible operation set by
Pr. 73
Analog input selection
.
Check the polarity of the frequency command.
Input
signal
Parameter
setting
Torque command is negative during torque control
under vector control.
Check the torque command value.
Check
points
Possible Cause
Countermeasures
Refer
to
page
Input
signal
Frequency 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.
Parameter
Setting
Pr. 1, Pr. 2, Pr. 18,calibration parameter C2 to C7
settings are improper.
Check the settings of
Pr. 1 Maximum frequency, Pr. 2
Minimum frequency, Pr. 18 High speed maximum
frequency.
Check the
calibration parameter C2 to C7
settings.
Pr. 31 to Pr. 36 (frequency jump)
settings are improper. Narrow down the range of frequency jump.
Load
Stall prevention (torque limit) function is activated
due to a heavy load.
Reduce the load weight.
—
Parameter
Setting
Set
Pr. 22 Stall prevention operation level (Torque limit
level)
higher according to the load. (Setting
Pr. 22
too
large may result in frequent overcurrent trip
(E.OC
).)
(
Motor
Check the capacities of the inverter and the motor.
—