Fuji Electric FRENIC-ECO, Instruction Manual

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6-5
Possible Causes What to Check and Suggested Measures
Check that there is no noise in the control signal wires from external sources.
Î Isolate the control signal wires from the main circuit wires as far as
possible.
Î Use shielded or twisted wires for the control signal.
(2) The external frequency
command source device
was used.
Check whether the frequency command source has not failed because of
noise from the inverter.
Î Connect a capacitor to the output terminal of the frequency command
source or insert a ferrite core in the signal wire. (Refer to Chapter 2
Section 2.3.7 "Wiring for control circuit terminals.")
(3) Frequency switching or
multistep frequency
command was enabled.
Check whether the relay signal for switching the frequency command is
chattering.
Î If the relay has a contact problem, replace the relay.
(4) The connection between
the inverter and the motor
was too long.
Check whether auto-torque boost or auto-energy saving operation is
enabled.
Î Set P02, P03, and P06 properly and perform auto-tuning in accordance
with P04.
Î Enable load selection for higher startup torque (F37 = 1) and check for
any vibration.
Î Make the output wire as short as possible.
Cancel the automatic control system--automatic torque boost and energy
saving operation (F37), overload prevention control (H70), and current
limiter (F43), then check that the motor vibration is suppressed.
Î Cancel the functions causing the vibration.
Î Readjust the data of the oscillation suppression gain (H80) currently set to
appropriate values.
(5) The inverter output is
hunting due to vibration
caused by low stiffness of
the load. Or the current is
irregularly oscillating due
to special motor
parameters.
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".
Î Decrease the carrier frequency (F26) or set the tone to "0" (F27=0).
[ 5 ] If grating sound can be heard from motor
Possible Causes What to Check and Suggested Measures
(1) The carrier frequency was
set too low.
Check the data of function codes F26 (Motor sound (carrier frequency)) and
F27 (Motor sound (tone)).
Î Increase the carrier frequency (F26).
Î Readjust the setting of F27 to appropriate value.
(2) The ambient temperature
of the inverter was too
high (when automatic
lowering of the carrier
frequency was enabled by
H98).
Measure the temperature inside the enclosure of the inverter.
Î If it is over 40 ℃ (104°F), lower it by improving the ventilation.
Î Lower the temperature of the inverter by reducing the load. (In the case of
a fan or a pump, lower the setting data of the frequency limiter (F15).)
Note: If you disable H98, an 0h1 , 0h3, or 0lu alarm may occur.
(3) Resonance with the load Check the precision of the mounting of the load or check whether there is
resonance with the enclosure or likes.
Î Disconnect the motor and run it without the inverter, and determine where
the resonance comes from. Upon locating the cause, improve the
characteristics of the source of the resonance.
Î Adjust the settings of C01 (Jump frequency 1) to C04 (Jump frequency
(band)) so as to avoid continuous running in the frequency range causing
resonance.