Fuji Electric FRENIC-MEGA - Motor Sound (Carrier Frequency) (F26); Motor Sound (Tone) (F27)

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F26, F27 Motor Sound (Carrier frequency and Tone) H98 (Protection/Maintenance Function (Mode selection))
 Motor Sound (Carrier frequency) (F26)
F26 controls the carrier frequency so as to reduce an audible noise generated by the motor or electromagnetic noise
from the inverter itself, and to decrease a leakage current from the main output (secondary) wirings.
Item Characteristics Remarks
0.75 to 16 kHz
0.4 to 55 kW (HD mode)
5.5 to 18.5 kW (LD mode)
0.75 to 10 kHz
75 to 400 kW (HD mode)
22 to 55 kW (LD mode)
0.75 to 6 kHz
500 and 630 kW (HD mode)
75 to 500 kW (LD mode)
0.75 to 4 kHz 630 kW (LD mode)
Carrier frequency
0.75 to 2 kHz 90 to 400 kW (MD mode)
Motor sound noise emission High ↔ Low
Motor temperature
(due to harmonics components)
High ↔ Low
Ripples in output current waveform Large ↔ Small
Leakage current Low ↔ High
Electromagnetic noise emission Low ↔ High
Inverter loss Low ↔ High
Specifying a too low carrier frequency will cause the output current waveform to have a large amount o
f
ripples. As a result, the motor loss increases, causing the motor temperature to rise. Furthermore, the large
amount of ripples tends to cause a current limiting alarm. When the carrier frequency is set to 1 kHz or below,
therefore, reduce the load so that the inverter output current comes to be 80% or less of the rated current.
When a high carrier frequency is specified, the temperature of the inverter may rise due to a surrounding
temperature rise or an increase of the load. If it happens, the inverter automatically decreases the carrie
r
frequency to prevent the inverter overload alarm
0lu . With consideration for motor noise, the automatic
reduction of carrier frequency can be disabled. Refer to the description of H98.
It is recommended to set the carrier frequency at 5 kHz or above under vector control without/with spee
d
sensor. DO NOT set it at 1 kHz or below.

Motor Sound (Tone) (F27)
F27 changes the motor running sound tone (only for motors under V/f control). This setting is effective when the carrier
frequency specified by function code F26 is 7 kHz or lower. Changing the tone level may reduce the high and harsh
running noise from the motor.
If the tone level is set too high, the output current may become unstable, or mechanical vibration and noise
may increase.
Also, this function code may not be very effective for certain types of motor.
Data for F27 Function
0 Disable (Tone level 0)
1 Enable (Tone level 1)
2 Enable (Tone level 2)
3 Enable (Tone level 3)
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