Motor Or Machine Is Making Abnormal Acoustic Noise; Motor Generates Heat Abnormally; Motor Rotates In The Opposite Direction - Mitsubishi Electric FR-CS84-012 Instruction Manual

6.6.2 Motor or machine is making abnormal acoustic
noise
Check Possible cause
point
Input
Disturbance due to EMI when the
signal
frequency or torque command is given
Parameter
through analog input terminal 2 or 4.
setting
No carrier frequency noises (metallic
noises) are generated.
Resonance occurs. (output frequency)
Parameter
Resonance occurs. (carrier frequency)
setting
Auto tuning is not performed under
General-purpose magnetic flux vector
control.
Gain adjustment during PID control is
insufficient.
Mechanical looseness
Others
Contact the motor manufacturer.
Operating with output phase loss.
Motor
6.6.3

Motor generates heat abnormally

Check Possible cause
point
The motor fan is not working.
(Dust is accumulated.)
Motor
Phase to phase insulation of the motor is
insufficient.
The inverter output voltage (U, V, W) are
Main
unbalanced.
Circuit
Parameter
Pr.71 Applied motor setting is incorrect.
setting
Motor current is too large
―
6.6.4

Motor rotates in the opposite direction

Check Possible cause
point
The phase sequence of output terminals U, V
Main
and W is incorrect.
Circuit
The start signals (STF and STR signals) are
connected improperly.
Input
The polarity of the frequency command is
signal
negative during the polarity reversible
operation set by Pr.73 Analog input selection.
222
6. PROTECTIVE FUNCTIONS
6.6 Check first when you have a trouble
Countermeasure
Take countermeasures against EMI.
Increase the Pr.74 Input filter time constant if steady operation
cannot be performed due to EMI or the like.
In the initial setting, Pr.240 Soft-PWM operation selection is enabled
to change motor noise to an unoffending complex tone. Therefore, no
carrier frequency noises (metallic noises) are generated.
Set Pr.240 = "0" to disable this function.
Set Pr.31 to Pr.36 (Frequency jump).
When it is desired to avoid resonance attributable to the natural
frequency of a mechanical system, these parameters allow resonant
frequencies to be jumped.
Change the Pr.72 PWM frequency selection setting.
Changing the PWM carrier frequency produces an effect on avoiding
the resonance frequency of a mechanical system or a motor.
Perform offline auto tuning
To stabilize the measured value, change the proportional band
(Pr.129) to a larger value, the integral time (Pr.130) to a slightly longer
time, and the differential time (Pr.134) to a slightly shorter time.
Check the calibration of set point and measured value.
Adjust machine/equipment so that there is no mechanical looseness. —
Check the motor wiring.
Countermeasure
Clean the motor fan.
Improve the environment.
Check the insulation of the motor.
Check the output voltage of the inverter.
Check the insulation of the motor.
Check the Pr.71 Applied motor setting.
Refer to "6.6.11 Motor current is too large".
Countermeasure
Connect the output side terminals (terminals U, V, and W)
correctly.
Check the connection. (STF: forward rotation, STR: reverse
rotation)
Check the polarity of the frequency command.
Refer to
page
48
134
92
118
92
147
152
—
Refer to
page
—
—
232
147
225
Refer to
page
31
35, 145
131