Fuji Electric FRN0001C2S-2A FRN0002C2S-2A FRN0004C2S-2A FRN0006C2S-2A FRN0010C2S-2A FRN0012C2S-2A FRN0020C2S-2A FRN0025C2S-2A FRN0033C2S-2A FR Instruction Manual page 188

Possible Causes
(4) The wiring length
between the inverter and
the motor is too long.
(5) The machinery is hunting
due to vibration caused
by low rigidity of the load.
Or the current is
irregularly oscillating due
to special motor
parameters.
[ 5 ] Grating sound is heard from the motor or the motor sound fluctuates.
Possible Causes
(1) The specified carrier
frequency is too low.
(2) The ambient
temperature of the
inverter was too high
(when automatic
lowering of the carrier
frequency was enabled
by H98).
(3) Resonance with the load
What to Check and Suggested Measures
Check whether auto-torque boost or auto-energy saving operation
is enabled.
 Perform auto-tuning of the inverter for every motor to be used.
 Select constant torque load (F37, A13 = 1) and check for any
vibration.
 Make the output wires as short as possible.
Once cancel all the automatic control systems--auto torque boost,
auto energy saving operation, overload prevention control, current
limiter, automatic deceleration (anti-regenerative control), and slip
compensation, and then check that the motor vibration comes to a
stop.
 Cancel the functions causing the vibration.
 Readjust the output current fluctuation damping gain (H80,
A41).
Check that the motor vibration is suppressed if you decrease the
level of F26 (Motor sound (Carrier frequency)) or set F27 (Motor
sound (Tone)) to "0."
 Decrease the carrier frequency (F26) or set the tone to "0" (F27
= 0).
What to Check and Suggested Measures
Check the data of function codes F26 (Motor sound (Carrier
frequency)) and F27 (Motor sound (Tone)).
 Increase the carrier frequency (F26).
 Change the setting of F27 to appropriate value.
Measure the temperature inside the panel where the inverter is
mounted.
 If it is over 40C (104F), lower it by improving the ventilation.
 Lower the temperature of the inverter by reducing the load. (For
fans or pumps, decrease the frequency limiter value (F15).)
Note: If you disable H98, an
Check the machinery mounting accuracy or check whether there is
resonance with the mounting base.
 Disconnect the motor from the machinery and run it alone, then
find where the resonance comes from. Upon locating the cause,
improve the characteristics of the source of the resonance.
 Adjust the settings of C01 (Jump frequency 1) to C04 (Jump
frequency (Hysteresis width)) so as to avoid continuous running
in the frequency range causing resonance.
6-6
or alarm may occur.
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