Fuji Electric FRENIC-Ace series - Page 250

5.3 Description of Function Codes
5-80
F26, F27
Motor Sound (Carrier frequency, Tone)
Related function codes: H98 Protection/Maintenance function (Mode selection)
■ Motor Sound (Carrier frequency) (F26)
Adjust carrier frequency. By changing carrier frequency, it is possible 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) wiring.
Setting frequency of carrier frequency differs depending on each model overload rating (ND/HD/HND/HHD).
Item Characteristics
Carrier frequency Low to High
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
Setting range of carrier frequency is as follows.
Modes 0.75 to 6kHz 0.75 to 10kHz 0.75 to 16kHz
FRNE2-2 (HHD) — — 0001 to 0115
FRNE2-2 (HND) — 0115 0001 to 0088
FRNE2-4 (ND) 0072 or above 0002 to 0059 —
FRNE2-4 (HD/HND) 0203 or above 0072 to 0168 0002 to 0059
FRNE2-4 (HHD) — 0203 or above 0002 to 0168
FRNE2-7 (HND/HHD) — — 0001 to 0012
Specifying a carrier frequency that is too low will cause the output current waveform to have a large
amount of ripple. As a result, the motor loss increases, causing the motor temperature to rise.
Furthermore, the large amount of ripple tends to cause a current limiting alarm. When the carrier
frequency is set to 1 kHz or lower, 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 the ambient
temperature rise or an increase of the load. If it happens, the inverter automatically decreases the carrier
frequency to prevent the inverter overload (
0lu
) . With consideration for motor noise, the automatic
reduction of carrier frequency ca
n be disabled. Refer to the description of H98.
It is recommended to set the carrier frequency at 5 kHz or above under vector control with speed sensor.
DO NOT set it at 1 kHz or below.
Running a PMSM at low carrier frequency may overheat the permanent magnet due to the output current
harmonics, resulting in demagnetization. When decreasing the carrier frequency setting, therefore, be
sure to check the allowable carrier frequency of the motor.
When using a Fuji standard PMSM with the rated load, decrease the carrier frequency. Setting a high
carrier frequency decreases not only the
harmonic components of the output current but also the allowed
continuous running inverter output current.